Command Reference, Cisco IOS XE Fuji 16.9.x (Catalyst 9200 Switches)

accept-lifetime

To set the time period during which the authentication key on a key chain is received as valid, use the accept-lifetime command in key chain key configuration mode. To revert to the default value, use the no form of this command.

accept-lifetime [ local ] start-time { infinite | end-time | duration seconds }

no accept-lifetime

Syntax Description


local	Specifies the time in local timezone.
`start-time`	Beginning time that the key specified by the key command is valid to be received. The syntax can be either of the following: `hh` : `mm` : `ss` `month` `date` `year` `hh` : `mm` : `ss` `date` `month` `year` `hh` : Hours `mm` : Minutes `ss` : Seconds `month` : First three letters of the month `date` : Date (1-31) `year` : Year (four digits) The default start time and the earliest acceptable date is January 1, 1993.
infinite	Key is valid to be received from the `start-time` value on.
`end-time`	Key is valid to be received from the `start-time` value until the `end-time` value. The syntax is the same as that for the `start-time` value. The `end-time` value must be after the `start-time` value. The default end time is an infinite time period.
duration `seconds`	Length of time (in seconds) that the key is valid to be received. The range is from 1 to 864000.

Command Default

The authentication key on a key chain is received as valid forever (the starting time is January 1, 1993, and the ending time is infinite).

Command Modes

Key chain key configuration (config-keychain-key)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Only DRP Agent, Enhanced Interior Gateway Routing Protocol (EIGRP), and Routing Information Protocol ( RIP) Version 2 use key chains.

Specify a start-time value and one of the following values: infinite , end-time , or duration seconds.

We recommend running Network Time Protocol (NTP) or some other time synchronization method if you assign a lifetime to a key.

If the last key expires, authentication will continue and an error message will be generated. To disable authentication, you must manually delete the last valid key.

Examples

The following example configures a key chain named chain1. The key named key1 will be accepted from 1:30 p.m. to 3:30 p.m. and will be sent from 2:00 p.m. to 3:00 p.m. The key named key2 will be accepted from 2:30 p.m. to 4:30 p.m. and will be sent from 3:00 p.m. to 4:00 p.m. The overlap allows for migration of keys or a discrepancy in the set time of the router. There is a 30-minute leeway on each side to handle time differences.

Device(config)# interface GigabitEthernet1/0/1
Device(config-if)# ip rip authentication key-chain chain1
Device(config-if)# ip rip authentication mode md5
Device(config-if)# exit
Device(config)# router rip
Device(config-router)# network 172.19.0.0
Device(config-router)# version 2
Device(config-router)# exit
Device(config)# key chain chain1
Device(config-keychain)# key 1
Device(config-keychain-key)# key-string key1
Device(config-keychain-key)# accept-lifetime 13:30:00 Jan 25 1996 duration 7200
Device(config-keychain-key)# send-lifetime 14:00:00 Jan 25 1996 duration 3600
Device(config-keychain-key)# exit
Device(config-keychain)# key 2
Device(config-keychain)# key-string key2
Device(config-keychain)# accept-lifetime 14:30:00 Jan 25 1996 duration 7200
Device(config-keychain)# send-lifetime 15:00:00 Jan 25 1996 duration 3600

The following example configures a key chain named chain1 for EIGRP address-family. The key named key1 will be accepted from 1:30 p.m. to 3:30 p.m. and be sent from 2:00 p.m. to 3:00 p.m. The key named key2 will be accepted from 2:30 p.m. to 4:30 p.m. and be sent from 3:00 p.m. to 4:00 p.m. The overlap allows for migration of keys or a discrepancy in the set time of the router. There is a 30-minute leeway on each side to handle time differences.

Device(config)# router eigrp 10
Device(config-router)# address-family ipv4 autonomous-system 4453
Device(config-router-af)# network 10.0.0.0
Device(config-router-af)# af-interface ethernet0/0
Device(config-router-af-interface)# authentication key-chain trees
Device(config-router-af-interface)# authentication mode md5
Device(config-router-af-interface)# exit
Device(config-router-af)# exit
Device(config-router)# exit
Device(config)# key chain chain1
Device(config-keychain)# key 1
Device(config-keychain-key)# key-string key1
Device(config-keychain-key)# accept-lifetime 13:30:00 Jan 25 1996 duration 7200
Device(config-keychain-key)# send-lifetime 14:00:00 Jan 25 1996 duration 3600
Device(config-keychain-key)# exit
Device(config-keychain)# key 2
Device(config-keychain-key)# key-string key2
Device(config-keychain-key)# accept-lifetime 14:30:00 Jan 25 1996 duration 7200
Device(config-keychain-key)# send-lifetime 15:00:00 Jan 25 1996 duration 3600

Related Commands


Command	Description
key	Identifies an authentication key on a key chain.
key chain	Defines an authentication key-chain needed to enable authentication for routing protocols.
key-string (authentication)	Specifies the authentication string for a key.
send-lifetime	Sets the time period during which an authentication key on a key chain is valid to be sent.
show key chain	Displays authentication key information.

area nssa

To configure a not-so-stubby area ( NSSA), use the area nssa command in router address family topology or router configuration mode. To remove the NSSA distinction from the area, use the no form of this command.

area nssa commandarea area-id nssa [no-redistribution] [default-information-originate [metric] [metric-type]] [no-summary] [nssa-only]

no area area-id nssa [no-redistribution] [default-information-originate [metric] [metric-type]] [no-summary] [nssa-only]

Syntax Description


`area-id`	Identifier for the stub area or NSSA. The identifier can be specified as either a decimal value or an IP address.
no-redistribution	(Optional) Used when the router is an NSSA Area Border Router (ABR) and you want the redistribute command to import routes only into the normal areas, but not into the NSSA area.
default-information- originate	(Optional) Used to generate a Type 7 default into the NSSA area. This keyword takes effect only on the NSSA ABR or the NSSA Autonomous System Boundary Router (ASBR).
metric	(Optional) Specifies the OSPF default metric.
metric-type	(Optional) Specifies the OSPF metric type for default routes.
no-summary	(Optional) Allows an area to be an NSSA but not have summary routes injected into it.
nssa-only	(Optional) Limits the default advertisement to this NSSA area by setting the propagate (P) bit in the type-7 LSA to zero.

Command Default

No NSSA area is defined.

Command Modes

Router address family topology configuration (config-router-af-topology) Router configuration (config-router)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

To remove the specified area from the software configuration, use the no area area-id command (with no other keywords). That is, the no area area-id command removes all area options, including area authentication , area default-cost , area nssa , area range , area stub , and area virtual-link .

Release 12.2(33)SRB

If you plan to configure the Multi-Topology Routing (MTR) feature, you need to enter the area nssa command in router address family topology configuration mode in order for this OSPF router configuration command to become topology-aware.

Examples

The following example makes area 1 an NSSA area:


router ospf 1
redistribute rip subnets
network 172.19.92.0 0.0.0.255 area 1
area 1 nssa

Related Commands


Command	Description
redistribute	Redistributes routes from one routing domain into another routing domain.

area virtual-link

To define an Open Shortest Path First (OSPF) virtual link, use the area virtual-link command in router address family topology, router configuration, or address family configuration mode. To remove a virtual link, use the no form of this command.

area area-id virtual-link router-id authentication key-chain chain-name [hello-interval seconds] [retransmit-interval seconds] [transmit-delay seconds] [dead-interval seconds] [ttl-security hops hop-count]

no area area-id virtual-link router-id authentication key-chain chain-name

Syntax Description

Table 1.
`area-id`	Area ID assigned to the virtual link. This can be either a decimal value or a valid IPv6 prefix. There is no default.
`router-id`	Router ID associated with the virtual link neighbor. The router ID appears in the show ip ospf or show ipv6 display command. There is no default.
authentication	Enables virtual link authentication.
key-chain	Configures a key-chain for cryptographic authentication keys.
`chain-name`	Name of the authentication key that is valid.
hello-interval `seconds`	(Optional) Specifies the time (in seconds) between the hello packets that the Cisco IOS software sends on an interface. The hello interval is an unsigned integer value to be advertised in the hello packets. The value must be the same for all routers and access servers attached to a common network. The range is from 1 to 8192. The default is 10.
retransmit-interval `seconds`	(Optional) Specifies the time (in seconds) between link-state advertisement (LSA) retransmissions for adjacencies belonging to the interface. The retransmit interval is the expected round-trip delay between any two routers on the attached network. The value must be greater than the expected round-trip delay. The range is from 1 to 8192. The default is 5.
transmit-delay `seconds`	(Optional) Specifies the estimated time (in seconds) required to send a link-state update packet on the interface. The integer value that must be greater than zero. LSAs in the update packet have their age incremented by this amount before transmission. The range is from 1 to 8192. The default value is 1.
dead-interval `seconds`	(Optional) Specifies the time (in seconds) that hello packets are not seen before a neighbor declares the router down. The dead interval is an unsigned integer value. The default is four times the hello interval, or 40 seconds. As with the hello interval, this value must be the same for all routers and access servers attached to a common network.
ttl-security hops `hop-count`	(Optional) Configures Time-to-Live (TTL) security on a virtual link. The `hop-count` argument range is from 1 to 254.

Command Default

No OSPF virtual link is defined.

Command Modes

Router address family topology configuration (config-router-af-topology)

Router configuration (config-router)

Address family configuration (config-router-af)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

In OSPF, all areas must be connected to a backbone area. A lost connection to the backbone can be repaired by establishing a virtual link.

The shorter the hello interval, the faster topological changes will be detected, but more routing traffic will ensue. The setting of the retransmit interval should be conservative, or needless retransmissions will result. The value should be larger for serial lines and virtual links.

You should choose a transmit delay value that considers the transmission and propagation delays for the interface.

To configure a virtual link in OSPF for IPv6, you must use a router ID instead of an address. In OSPF for IPv6, the virtual link takes the router ID rather than the IPv6 prefix of the remote router.

Use the ttl-security hops hop-count keywords and argument to enable checking of TTL values on OSPF packets from neighbors or to set TTL values sent to neighbors. This feature adds an extra layer of protection to OSPF.

Note

In order for a virtual link to be properly configured, each virtual link neighbor must include the transit area ID and the corresponding virtual link neighbor router ID. To display the router ID, use the show ip ospf or the show ipv6 ospf command in privileged EXEC mode.

Note

To remove the specified area from the software configuration, use the no area area-id command (with no other keywords). That is, the no area area-id command removes all area options, such as area default-cost , area nssa , area range , area stub , and area virtual-link .

Release 12.2(33)SRB

If you plan to configure the Multitopology Routing (MTR) feature, you need to enter the area virtual-link command in router address family topology configuration mode in order for this OSPF router configuration command to become topology-aware.

Examples

The following example establishes a virtual link with default values for all optional parameters:


Device(config)# ipv6 router ospf 1
Device(config)# log-adjacency-changes
Device(config)# area 1 virtual-link 192.168.255.1

The following example establishes a virtual link in OSPF for IPv6:


Device(config)# ipv6 router ospf 1
Device(config)# log-adjacency-changes
Device(config)# area 1 virtual-link 192.168.255.1 hello-interval 5

The following example shows how to configure TTL security for a virtual link in OSPFv3 for IPv6:


Device(config)# router ospfv3 1
Device(config-router)# address-family ipv6 unicast vrf vrf1
Device(config-router-af)# area 1 virtual-link 10.1.1.1 ttl-security hops 10

The following example shows how to configure the authentication using a key chain for virtual-links:


Device(config)# area 1 virtual-link 192.168.255.1 authentication key-chain ospf-chain-1

Related Commands


Command	Description
area	Configures OSPFv3 area parameters.
show ip ospf	Enables the display of general information about OSPF routing processes.
show ipv6 ospf	Enables the display of general information about OSPF routing processes.
ttl-security hops	Enables checking of TTL values on OSPF packets from neighbors or setting TTL values sent to neighbors.

default-information originate (OSPF)

To generate a default external route into an Open Shortest Path First (OSPF) routing domain, use the default-information originate command in router configuration or router address family topology configuration mode. To disable this feature, use the no form of this command.

default-information originate [always] [metric metric-value] [metric-type type-value] [route-map map-name]

no default-information originate [always] [metric metric-value] [metric-type type-value] [route-map map-name]

Syntax Description

always

(Optional) Always advertises the default route regardless of whether the software has a default route.

Note

The always keyword includes the following exception when the route map is used. When a route map is used, the origination of the default route by OSPF is not bound to the existence of a default route in the routing table and the always keyword is ignored.

metric metric-value

(Optional) Metric used for generating the default route. If you omit a value and do not specify a value using the default-metric router configuration command, the default metric value is 10. The value used is specific to the protocol.

metric-type type-value

(Optional) External link type associated with the default route that is advertised into the OSPF routing domain. It can be one of the following values:

Type 1 external route.
Type 2 external route.

The default is type 2 external route.

route-map map-name

(Optional) The routing process will generate the default route if the route map is satisfied.

Command Default

This command is disabled by default. No default external route is generated into the OSPF routing domain.

Command Modes

Router configuration (config-router) Router address family topology configuration (config-router-af-topology)

Command History



Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Whenever you use the redistribute or the default-information router configuration command to redistribute routes into an OSPF routing domain, the Cisco IOS software automatically becomes an Autonomous System Boundary Router (ASBR). However, an ASBR does not, by default, generate a default route into the OSPF routing domain. The software must still have a default route for itself before it generates one, except when you have specified the always keyword.

When a route map is used, the origination of the default route by OSPF is not bound to the existence of a default route in the routing table.

Release 12.2(33)SRB

If you plan to configure the Multi-Topology Routing (MTR) feature, you need to enter the default-information originate command in router address family topology configuration mode in order for this OSPF router configuration command to become topology-aware.

Examples

The following example specifies a metric of 100 for the default route that is redistributed into the OSPF routing domain and specifies an external metric type of 1:


router ospf 109
redistribute eigrp 108 metric 100 subnets
default-information originate metric 100 metric-type 1

Related Commands


Command	Description
default-information	Accepts exterior or default information into Enhanced Interior Gateway Routing Protocol (EIGRP) processes.
default-metric	Sets default metric values for routes.
redistribute (IP)	Redistributes routes from one routing domain into another routing domain.

distance (OSPF)

To define an administrative distance, use the distance command in router configuration mode or VRF configuration mode. To remove the distance command and restore the system to its default condition, use the no form of this command.

distance weight [ip-address wildcard-mask [access-list name]]

no distance weight ip-address wildcard-mask [access-list-name]

Syntax Description


`weight`	Administrative distance. Range is 10 to 255. Used alone, the `weight` argument specifies a default administrative distance that the software uses when no other specification exists for a routing information source. Routes with a distance of 255 are not installed in the routing table. The table in the “Usage Guidelines” section lists the default administrative distances.
`ip-address`	(Optional) IP address in four-part dotted-decimal notation.
`wildcard-mask`	(Optional) Wildcard mask in four-part, dotted-decimal format. A bit set to 1 in the `wildcard-mask` argument instructs the software to ignore the corresponding bit in the address value.
`access-list-name`	(Optional) Name of an IP access list to be applied to incoming routing updates.

Command Default

If this command is not specified, the administrative distance is the default. The table in the “Usage Guidelines” section lists the default administrative distances.

Command Modes

Router configuration (config-router)

VRF configuration (config-vrf)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the appropriate task IDs. If the user group assignment is preventing you from using a command contact your AAA administrator for assistance.

An administrative distance is an integer from 10 to 255. In general, the higher the value, the lower the trust rating. An administrative distance of 255 means that the routing information source cannot be trusted at all and should be ignored. Weight values are subjective; no quantitative method exists for choosing weight values.

If an access list is used with this command, it is applied when a network is being inserted into the routing table. This behavior allows you to filter networks based on the IP prefix supplying the routing information. For example, you could filter possibly incorrect routing information from networking devices not under your administrative control.

The order in which you enter distance commands can affect the assigned administrative distances, as shown in the “Examples” section. The following table lists default administrative distances.

Table 2. Default Administrative Distances
Rate Source	Default Distance
Connected interface	0
Static route out on interface	0
Static route to next hop	1
EIGRP summary route	5
External BGP	20
Internal EIGRP	90
OSPF	110
IS-IS	115
RIP version 1 and 2	120
External EIGRP	170
Internal BGP	200
Unknown	255

Task ID


Task ID	Operations
ospf	read, write

Examples

In the following example, the router ospf command sets up Open Shortest Path First (OSPF) routing instance 1. The first distance command sets the default administrative distance to 255, which instructs the software to ignore all routing updates from networking devices for which an explicit distance has not been set. The second distance command sets the administrative distance for all devices on the network 192.168.40.0 to 90.


Device#configure terminal
Device(config)#router ospf 1
Device(config-ospf)#distance 255
Device(config-ospf)#distance 90 192.168.40.0 0.0.0.255

Related Commands


Command	Description
distance bgp	Allows the use of external, internal, and local administrative distances that could be a better route to a BGP node.
distance ospf	Allows the use of external, internal, and local administrative distances that could be a better route to an OSPF node.
router ospf	Configures the OSPF routing process.

eigrp log-neighbor-changes

To enable the logging of changes in Enhanced Interior Gateway Routing Protocol (EIGRP) neighbor adjacencies, use the eigrp log-neighbor-changes command in router configuration mode, address-family configuration mode, or service-family configuration mode. To disable the logging of changes in EIGRP neighbor adjacencies, use the no form of this command.

eigrp log-neighbor-changes

no eigrp log-neighbor-changes

Syntax Description

This command has no arguments or keywords.

Command Default

Adjacency changes are logged.

Command Modes

Router configuration (config-router) Address-family configuration (config-router-af) Service-family configuration (config-router-sf)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

This command enables the logging of neighbor adjacency changes to monitor the stability of the routing system and to help detect problems. Logging is enabled by default. To disable the logging of neighbor adjacency changes, use the no form of this command.

To enable the logging of changes for EIGRP address-family neighbor adjacencies, use the eigrp log-neighbor-changes command in address-family configuration mode.

To enable the logging of changes for EIGRP service-family neighbor adjacencies, use the eigrp log-neighbor-changes command in service-family configuration mode.

Examples

The following configuration disables logging of neighbor changes for EIGRP process 209:


Device(config)# router eigrp 209
Device(config-router)# no eigrp log-neighbor-changes

The following configuration enables logging of neighbor changes for EIGRP process 209:


Device(config)# router eigrp 209
Device(config-router)# eigrp log-neighbor-changes

The following example shows how to disable logging of neighbor changes for EIGRP address-family with autonomous-system 4453:


Device(config)# router eigrp virtual-name
Device(config-router)# address-family ipv4 autonomous-system 4453 
Device(config-router-af)# no eigrp log-neighbor-changes
Device(config-router-af)# exit-address-family

The following configuration enables logging of neighbor changes for EIGRP service-family process 209:


Device(config)# router eigrp 209
Device(config-router)# service-family ipv4 autonomous-system 4453 
Device(config-router-sf)# eigrp log-neighbor-changes
Device(config-router-sf)# exit-service-family

Related Commands


Command	Description
address-family (EIGRP)	Enters address-family configuration mode to configure an EIGRP routing instance.
exit-address-family	Exits address-family configuration mode.
exit-service-family	Exits service-family configuration mode.
router eigrp	Configures the EIGRP routing process.
service-family	Specifies service-family configuration mode.

ip authentication key-chain eigrp

To enable authentication of Enhanced Interior Gateway Routing Protocol (EIGRP) packets, use the ip authentication key-chain eigrp command in interface configuration mode. To disable such authentication, use the no form of this command.

ip authentication key-chain eigrp as-number key-chain

no ip authentication key-chain eigrp as-number key-chain

Syntax Description


`as-number`	Autonomous system number to which the authentication applies.
`key-chain`	Name of the authentication key chain.

Command Default

No authentication is provided for EIGRP packets.

Command Modes

Interface configuration (config-if) Virtual network interface (config-if-vnet)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Examples

The following example applies authentication to autonomous system 2 and identifies a key chain named SPORTS:


Device(config-if)#ip authentication key-chain eigrp 2 SPORTS

Related Commands


Command	Description
accept-lifetime	Sets the time period during which the authentication key on a key chain is received as valid.
ip authentication mode eigrp	Specifies the type of authentication used in EIGRP packets.
key	Identifies an authentication key on a key chain.
key chain	Enables authentication of routing protocols.
key-string (authentication)	Specifies the authentication string for a key.
send-lifetime	Sets the time period during which an authentication key on a key chain is valid to be sent.

ip authentication mode eigrp

To specify the type of authentication used in Enhanced Interior Gateway Routing Protocol (EIGRP) packets, use the ip authentication mode eigrp command in interface configuration mode. To disable that type of authentication, use the no form of this command.

ip authentication mode eigrp as-number md5

no ip authentication mode eigrp as-number md5

Syntax Description


`as-number`	Autonomous system number.
md5	Keyed Message Digest 5 ( MD5) authentication.

Command Default

No authentication is provided for EIGRP packets.

Command Modes

Interface configuration (config-if) Virtual network interface (config-if-vnet)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Configure authentication to prevent unapproved sources from introducing unauthorized or false routing messages. When authentication is configured, an MD5 keyed digest is added to each EIGRP packet in the specified autonomous system.

Examples

The following example configures the interface to use MD5 authentication in EIGRP packets in autonomous system 10:


Device(config-if)#ip authentication mode eigrp 10 md5

Related Commands


Command	Description
accept-lifetime	Sets the time period during which the authentication key on a key chain is received as valid.
ip authentication key-chain eigrp	Enables authentication of EIGRP packets.
key	Identifies an authentication key on a key chain.
key chain	Enables authentication of routing protocols.
key-string (authentication)	Specifies the authentication string for a key.
send-lifetime	Sets the time period during which an authentication key on a key chain is valid to be sent.

ip bandwidth-percent eigrp

To configure the percentage of bandwidth that may be used by Enhanced Interior Gateway Routing Protocol (EIGRP) on an interface, use the ip bandwidth-percent eigrp command in interface configuration mode. To restore the default value, use the no form of this command.

ip bandwidth-percent eigrp as-number percent

no ip bandwidth-percent eigrp as-number percent

Syntax Description


`as-number`	Autonomous system number.
`percent`	Percent of bandwidth that EIGRP may use.

Command Default

EIGRP may use 50 percent of available bandwidth.

Command Modes

Interface configuration (config-if) Virtual network interface (config-if-vnet)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

EIGRP will use up to 50 percent of the bandwidth of a link, as defined by the bandwidth interface configuration command. This command may be used if some other fraction of the bandwidth is desired. Note that values greater than 100 percent may be configured. The configuration option may be useful if the bandwidth is set artificially low for other reasons.

Examples

The following example allows EIGRP to use up to 75 percent (42 kbps) of a 56-kbps serial link in autonomous system 209:


Device(config)#interface serial 0
Device(config-if)#bandwidth 56
Device(config-if)#ip bandwidth-percent eigrp 209 75

Related Commands


Command	Description
bandwidth (interface)	Sets a bandwidth value for an interface.

ip cef load-sharing algorithm

To select a Cisco Express Forwarding load-balancing algorithm, use theip cef load-sharing algorithm command in global configuration mode. To return to the default universal load-balancing algorithm, use the no form of this command.

ip cef load-sharing algorithm {original | [universal [id] ]}

no ip cef load-sharing algorithm

Syntax Description


original	Sets the load-balancing algorithm to the original algorithm based on a source and destination hash.
universal	Sets the load-balancing algorithm to the universal algorithm that uses a source and destination and an ID hash.
`id`	(Optional) Fixed identifier.

Command Default

The universal load-balancing algorithm is selected by default. If you do not configure the fixed identifier for a load-balancing algorithm, the router automatically generates a unique ID.

Command Modes

Global configuration (config)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

The original Cisco Express Forwarding load-balancing algorithm produced distortions in load sharing across multiple devices because of the use of the same algorithm on every device. When the load-balancing algorithm is set to universal mode, each device on the network can make a different load sharing decision for each source-destination address pair, and that resolves load-balancing distortions.

Examples

The following example shows how to enable the Cisco Express Forwarding original load-balancing algorithm:

Device> enable
Device# configure terminal
Device(config)# ip cef load-sharing algorithm original
Device(config)# exit

Related Commands


Command	Description
ip load-sharing	Enables load balancing for Cisco Express Forwarding.

ip prefix-list

To create a prefix list or to add a prefix-list entry, use the ip prefix-list command in global configuration mode. To delete a prefix-list entry, use the no form of this command.

ip prefix-list {list-name [seq number] {deny | permit} network/length [ge ge-length] [le le-length] | description description | sequence-number}

no ip prefix-list {list-name [seq number] [ {deny | permit} network/length [ge ge-length] [le le-length]] | description description | sequence-number}

Syntax Description

list-name

Configures a name to identify the prefix list. Do not use the word “detail” or “summary” as a list name because they are keywords in the show ip prefix-list command.

seq

(Optional) Applies a sequence number to a prefix-list entry.

number

(Optional) Integer from 1 to 4294967294. If a sequence number is not entered when configuring this command, default sequence numbering is applied to the prefix list. The number 5 is applied to the first prefix entry, and subsequent unnumbered entries are incremented by 5.

deny

Denies access for a matching condition.

permit

Permits access for a matching condition.

network / length

Configures the network address and the length of the network mask in bits. The network number can be any valid IP address or prefix. The bit mask can be a number from 1 to 32.

ge

(Optional) Specifies the lesser value of a range (the “from” portion of the range description) by applying the ge-length argument to the range specified.

Note

The ge keyword represents the greater than or equal to operator.

ge-length

(Optional) Represents the minimum prefix length to be matched.

le

(Optional) Specifies the greater value of a range (the “to” portion of the range description) by applying the le-length argument to the range specified.

Note

The le keyword represents the less than or equal to operator.

le-length

(Optional) Represents the maximum prefix length to be matched.

description

(Optional) Configures a descriptive name for the prefix list.

description

(Optional) Descriptive name of the prefix list, from 1 to 80 characters in length.

sequence-number

(Optional) Enables or disables the use of sequence numbers for prefix lists.

Command Default

No prefix lists or prefix-list entries are created.

Command Modes

Global configuration (config)

Command History

Table 3.
Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Use the ip prefix-list command to configure IP prefix filtering. Prefix lists are configured with permit or deny keywords to either permit or deny a prefix based on a matching condition. An implicit deny is applied to traffic that does not match any prefix-list entry.

A prefix-list entry consists of an IP address and a bit mask. The IP address can be for a classful network, a subnet, or a single host route. The bit mask is a number from 1 to 32.

Prefix lists are configured to filter traffic based on a match of an exact prefix length or a match within a range when the ge and le keywords are used. The ge and le keywords are used to specify a range of prefix lengths and provide more flexible configuration than using only the network/length argument. A prefix list is processed using an exact match when neither the ge nor le keyword is specified. If only the ge value is specified, the range is the value entered for the ge ge-length argument to a full 32-bit length. If only the le value is specified, the range is from the value entered for the network/length argument to the le le-length argument. If both the ge ge-length and le le-length keywords and arguments are entered, the range is between the values used for the ge-length and le-length arguments.

The following formula shows this behavior:

length <ge ge-length <le le-length <= 32

If the seq keyword is configured without a sequence number, the default sequence number is 5. In this scenario, the first prefix-list entry is assigned the number 5 and subsequent prefix list entries increment by 5. For example, the next two entries would have sequence numbers 10 and 15. If a sequence number is entered for the first prefix list entry but not for subsequent entries, the subsequent entry numbers increment by 5. For example, if the first configured sequence number is 3, subsequent entries will be 8, 13, and 18. Default sequence numbers can be suppressed by entering the no ip prefix-list command with the seq keyword.

Evaluation of a prefix list starts with the lowest sequence number and continues down the list until a match is found. When an IP address match is found, the permit or deny statement is applied to that network and the remainder of the list is not evaluated.

Tip

For best performance, the most frequently processed prefix list statements should be configured with the lowest sequence numbers. The seq number keyword and argument can be used for resequencing.

A prefix list is applied to inbound or outbound updates for a specific peer by entering the neighbor prefix-list command. Prefix list information and counters are displayed in the output of the show ip prefix-list command. Prefix-list counters can be reset by entering the clear ip prefix-list command.

Examples

In the following example, a prefix list is configured to deny the default route 0.0.0.0/0:


Device(config)#ip prefix-list RED deny 0.0.0.0/0

In the following example, a prefix list is configured to permit traffic from the 172.16.1.0/24 subnet:


Device(config)#ip prefix-list BLUE permit 172.16.1.0/24

In the following example, a prefix list is configured to permit routes from the 10.0.0.0/8 network that have a mask length that is less than or equal to 24 bits:


Device(config)#ip prefix-list YELLOW permit 10.0.0.0/8 le 24

In the following example, a prefix list is configured to deny routes from the 10.0.0.0/8 network that have a mask length that is greater than or equal to 25 bits:


Device(config)#ip prefix-list PINK deny 10.0.0.0/8 ge 25

In the following example, a prefix list is configured to permit routes from any network that have a mask length from 8 to 24 bits:


Device(config)#ip prefix-list GREEN permit 0.0.0.0/0 ge 8 le 24

In the following example, a prefix list is configured to deny any route with any mask length from the 10.0.0.0/8 network:


Device(config)#ip prefix-list ORANGE deny 10.0.0.0/8 le 32

Related Commands


Command	Description
clear ip prefix-list	Resets the prefix list entry counters.
ip prefix-list description	Adds a text description of a prefix list.
ip prefix-list sequence	Enables or disables default prefix-list sequencing.
match ip address	Distributes any routes that have a destination network number address that is permitted by a standard or extended access list, and performs policy routing on packets.
neighbor prefix-list	Filters routes from the specified neighbor using a prefix list.
show ip prefix-list	Displays information about a prefix list or prefix list entries.

ip hello-interval eigrp

To configure the hello interval for an Enhanced Interior Gateway Routing Protocol (EIGRP) process, use the ip hello-interval eigrp command in interface configuration mode. To restore the default value, use the no form of this command.

ip hello-interval eigrp as-number seconds

no ip hello-interval eigrp as-number [seconds]

Syntax Description


`as-number`	Autonomous system number.
`seconds`	Hello interval (in seconds). The range is from 1 to 65535.

Command Default

The hello interval for low-speed, nonbroadcast multiaccess (NBMA) networks is 60 seconds and 5 seconds for all other networks.

Command Modes

Interface configuration (config-if) Virtual network interface (config-if-vnet)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

The default of 60 seconds applies only to low-speed, NBMA media. Low speed is considered to be a rate of T1 or slower, as specified with the bandwidth interface configuration command. Note that for the purposes of EIGRP, Frame Relay and Switched Multimegabit Data Service (SMDS) networks may be considered to be NBMA. These networks are considered NBMA if the interface has not been configured to use physical multicasting; otherwise, they are considered not to be NBMA.

Examples

The following example sets the hello interval for Ethernet interface 0 to 10 seconds:


Device(config)#interface ethernet 0
Device(config-if)#ip hello-interval eigrp 109 10

Related Commands


Command	Description
bandwidth (interface)	Sets a bandwidth value for an interface.
ip hold-time eigrp	Configures the hold time for a particular EIGRP routing process designated by the autonomous system number.

ip hold-time eigrp

To configure the hold time for an Enhanced Interior Gateway Routing Protocol (EIGRP) process, use the ip hold-time eigrp command in interface configuration mode. To restore the default value, use the no form of this command.

ip hold-time eigrp as-number seconds

no ip hold-time eigrp as-number seconds

Syntax Description


`as-number`	Autonomous system number.
`seconds`	Hold time (in seconds). The range is from 1 to 65535.

Command Default

The EIGRP hold time is 180 seconds for low-speed, nonbroadcast multiaccess (NBMA) networks and 15 seconds for all other networks.

Command Modes

Interface configuration (config-if) Virtual network interface (config-if-vnet)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

On very congested and large networks, the default hold time might not be sufficient time for all routers and access servers to receive hello packets from their neighbors. In this case, you may want to increase the hold time.

We recommend that the hold time be at least three times the hello interval. If a router does not receive a hello packet within the specified hold time, routes through this router are considered unavailable.

Increasing the hold time delays route convergence across the network.

The default of 180 seconds hold time and 60 seconds hello interval apply only to low-speed, NBMA media. Low speed is considered to be a rate of T1 or slower, as specified with the bandwidth interface configuration command.

Examples

The following example sets the hold time for Ethernet interface 0 to 40 seconds:


Device(config)#interface ethernet 0
Device(config-if)#ip hold-time eigrp 109 40

Related Commands


Command	Description
bandwidth (interface)	Sets a bandwidth value for an interface.
ip hello-interval eigrp	Configures the hello interval for the EIGRP routing process designated by an autonomous system number.

ip load-sharing

To enable load balancing for Cisco Express Forwarding on an interface, use the ip load-sharing command in interface configuration mode. To disable load balancing for Cisco Express Forwarding on the interface, use the no form of this command.

ip load-sharing { per-destination }

no ip load-sharing

Syntax Description


per-destination	Enables per-destination load balancing for Cisco Express Forwarding on the interface.

Command Default

Per-destination load balancing is enabled by default when you enable Cisco Express Forwarding.

Command Modes

Interface configuration (config-if)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Per-destination load balancing allows the device to use multiple, equal-cost paths to achieve load sharing. Packets for a given source-destination host pair are guaranteed to take the same path, even if multiple, equal-cost paths are available. Traffic for different source-destination host pairs tends to take different paths.

Examples

The following example shows how to enable per-destination load balancing:

Device> enable 
Device# configure terminal
Device(config)# interface gigabitethernet 1/0/1
Device(config-if)# ip load-sharing per-destination

ip ospf database-filter all out

To filter outgoing link-state advertisements (LSAs) to an Open Shortest Path First (OSPF) interface, use the ip ospf database-filter all out command in interface or virtual network interface configuration modes. To restore the forwarding of LSAs to the interface, use the no form of this command.

ip ospf database-filter all out [disable]

no ip ospf database-filter all out

Syntax Description

disable

(Optional) Disables the filtering of outgoing LSAs to an OSPF interface; all outgoing LSAs are flooded to the interface.

Note

This keyword is available only in virtual network interface mode.

Command Default

This command is disabled by default. All outgoing LSAs are flooded to the interface.

Command Modes

Interface configuration (config-if)

Virtual network interface (config-if-vnet)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

This command performs the same function that the neighbor database-filter command performs on a neighbor basis.

If the ip ospf database-filter all out command is enabled for a virtual network and you want to disable it, use the disable keyword in virtual network interface configuration mode.

Examples

The following example prevents filtering of OSPF LSAs to broadcast, nonbroadcast, or point-to-point networks reachable through Ethernet interface 0:


Device(config)#interface ethernet 0
Device(config-if)#ip ospf database-filter all out

Related Commands


Command	Description
neighbor database-filter	Filters outgoing LSAs to an OSPF neighbor.

ip ospf name-lookup

To configure Open Shortest Path First (OSPF) to look up Domain Name System (DNS) names for use in all OSPF show EXEC command displays, use the ip ospf name-lookup command in global configuration mode. To disable this function, use the no form of this command.

ip ospf name-lookup

noipospfname-lookup

Syntax Description

This command has no arguments or keywords.

Command Default

This command is disabled by default.

Command Modes

Global configuration

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

This command makes it easier to identify a router because the router is displayed by name rather than by its router ID or neighbor ID.

Examples

The following example configures OSPF to look up DNS names for use in all OSPF show EXEC command displays:


Device(config)#ip ospf name-lookup

ip split-horizon eigrp

To enable Enhanced Interior Gateway Routing Protocol (EIGRP) split horizon, use the ip split-horizon eigrp command in interface configuration mode. To disable split horizon, use the no form of this command.

ip split-horizon eigrp as-number

no ip split-horizon eigrp as-number

Syntax Description


`as-number`	Autonomous system number.

Command Default

The behavior of this command is enabled by default.

Command Modes

Interface configuration (config-if)

Virtual network interface (config-if-vnet)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Use the no ip split-horizon eigrp command to disable EIGRP split horizon in your configuration.

Examples

The following is an example of how to enable EIGRP split horizon:


Device(config-if)#ip split-horizon eigrp 101

Related Commands


Command	Description
ip split-horizon (RIP)	Enables the split horizon mechanism.
neighbor (EIGRP)	Defines a neighboring router with which to exchange routing information.

ip summary-address eigrp

To configure address summarization for the Enhanced Interior Gateway Routing Protocol (EIGRP) on a specified interface, use the ip summary-address eigrp command in interface configuration or virtual network interface configuration mode. To disable the configuration, use the no form of this command.

ip summary-address eigrp as-number ip-address mask [admin-distance] [leak-map name]

no ip summary-address eigrp as-number ip-address mask

Syntax Description

as-number

Autonomous system number.

ip-address

Summary IP address to apply to an interface.

mask

Subnet mask.

admin-distance

(Optional) Administrative distance. Range: 0 to 255.

Note

Starting with Cisco IOS XE Release 3.2S, the admin-distance argument was removed. Use the summary-metric command to configure the administrative distance.

leak-map name

(Optional) Specifies the route-map reference that is used to configure the route leaking through the summary.

Command Default

An administrative distance of 5 is applied to EIGRP summary routes.
EIGRP automatically summarizes to the network level, even for a single host route.
No summary addresses are predefined.
The default administrative distance metric for EIGRP is 90.

Command Modes

Interface configuration (config-if)

Virtual network interface configuration (config-if-vnet)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

The ip summary-address eigrp command is used to configure interface-level address summarization. EIGRP summary routes are given an administrative-distance value of 5. The administrative-distance metric is used to advertise a summary without installing it in the routing table.

By default, EIGRP summarizes subnet routes to the network level. The no auto-summary command can be entered to configure the subnet-level summarization.

The summary address is not advertised to the peer if the administrative distance is configured as 255.

EIGRP Support for Leaking Routes

Configuring the leak-map keyword allows a component route that would otherwise be suppressed by the manual summary to be advertised. Any component subset of the summary can be leaked. A route map and access list must be defined to source the leaked route.

The following is the default behavior if an incomplete configuration is entered:

If the leak-map keyword is configured to reference a nonexistent route map, the configuration of this keyword has no effect. The summary address is advertised but all component routes are suppressed.
If the leak-map keyword is configured but the access list does not exist or the route map does not reference the access list, the summary address and all component routes are advertised.

If you are configuring a virtual-network trunk interface and you configure the ip summary-address eigrp command, the admin-distance value of the command is not inherited by the virtual networks running on the trunk interface because the administrative distance option is not supported in the ip summary-address eigrp command on virtual network subinterfaces.

Examples

The following example shows how to configure an administrative distance of 95 on Ethernet interface 0/0 for the 192.168.0.0/16 summary address:


Device(config)#router eigrp 1
Device(config-router)#no auto-summary
Device(config-router)#exit
Device(config)#interface Ethernet 0/0
Device(config-if)#ip summary-address eigrp 1 192.168.0.0 255.255.0.0 95

The following example shows how to configure the 10.1.1.0/24 subnet to be leaked through the 10.2.2.0 summary address:


Device(config)#router eigrp 1 
Device(config-router)#exit 
Device(config)#access-list 1 permit 10.1.1.0 0.0.0.255
Device(config)#route-map LEAK-10-1-1 permit 10
Device(config-route-map)#match ip address 1
Device(config-route-map)#exit
Device(config)#interface Serial 0/0
Device(config-if)#ip summary-address eigrp 1 10.2.2.0 255.0.0.0 leak-map LEAK-10-1-1
Device(config-if)#end

The following example configures GigabitEthernet interface 0/0/0 as a virtual network trunk interface:


Device(config)#interface gigabitethernet 0/0/0
Device(config-if)#vnet global
Device(config-if-vnet)#ip summary-address eigrp 1 10.3.3.0 255.0.0.0 33

Related Commands


Command	Description
auto-summary (EIGRP)	Configures automatic summarization of subnet routes to network-level routes (default behavior).
summary-metric	Configures fixed metrics for an EIGRP summary aggregate address.

metric weights (EIGRP)

To tune the Enhanced Interior Gateway Routing Protocol (EIGRP) metric calculations, use the metric weights command in router configuration mode or address family configuration mode. To reset the values to their defaults, use the no form of this command.

Router Configuration

metric weights tos k1 k2 k3 k4 k5

no metric weights

Address Family Configuration

metric weights tos [k1 [k2 [k3 [k4 [k5 [k6] ]]]]]

no metric weights

Syntax Description

tos

Type of service. This value must always be zero.

k1 k2 k3 k4 k5 k6

(Optional) Constants that convert an EIGRP metric vector into a scalar quantity. Valid values are 0 to 255. Given below are the default values:

k1: 1
k2: 0
k3: 1
k4: 0
k5: 0
k6: 0

Note

In address family configuration mode, if the values are not specified, default values are configured. The k6 argument is supported only in address family configuration mode.

Command Default

EIGRP metric K values are set to their default values.

Command Modes

Router configuration (config-router)

Address family configuration (config-router-af)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Use this command to alter the default behavior of EIGRP routing and metric computation and to allow the tuning of the EIGRP metric calculation for a particular type of service (ToS).

If k5 equals 0, the composite EIGRP metric is computed according to the following formula:

metric = [k1 * bandwidth + (k2 * bandwidth)/(256 – load) + k3 * delay + K6 * extended metrics]

If k5 does not equal zero, an additional operation is performed:

metric = metric * [k5/(reliability + k4)]

Scaled Bandwidth= 10⁷/minimum interface bandwidth (in kilobits per second) * 256

Delay is in tens of microseconds for classic mode and pico seconds for named mode. In classic mode, a delay of hexadecimal FFFFFFFF (decimal 4294967295) indicates that the network is unreachable. In named mode, a delay of hexadecimal FFFFFFFFFFFF (decimal 281474976710655) indicates that the network is unreachable.

Reliability is given as a fraction of 255. That is, 255 is 100 percent reliability or a perfectly stable link.

Load is given as a fraction of 255. A load of 255 indicates a completely saturated link.

Examples

The following example shows how to set the metric weights to slightly different values than the defaults:


Device(config)#router eigrp 109
Device(config-router)#network 192.168.0.0
Device(config-router)#metric weights 0 2 0 2 0 0

The following example shows how to configure an address-family metric weight to ToS: 0; K1: 2; K2: 0; K3: 2; K4: 0; K5: 0; K6:1:


Device(config)#router eigrp virtual-name
Device(config-router)#address-family ipv4 autonomous-system 4533
Device(config-router-af)#metric weights 0 2 0 2 0 0 1

Related Commands


Command	Description
address-family (EIGRP)	Enters address family configuration mode to configure an EIGRP routing instance.
bandwidth (interface)	Sets a bandwidth value for an interface.
delay (interface)	Sets a delay value for an interface.
ipv6 router eigrp	Configures an IPv6 EIGRP routing process.
metric holddown	Keeps new EIGRP routing information from being used for a certain period of time.
metric maximum-hops	Causes IP routing software to advertise routes with a hop count higher than what is specified by the command (EIGRP only) as unreachable routes.
router eigrp	Configures an EIGRP routing process.

neighbor description

To associate a description with a neighbor, use the neighbor description command in router configuration mode or address family configuration mode. To remove the description, use the no form of this command.

neighbor {ip-address | peer-group-name} description text

no neighbor {ip-address | peer-group-name} description [text]

Syntax Description


`ip-address`	IP address of the neighbor.
`peer-group-name`	Name of an EIGRP peer group. This argument is not available in address-family configuration mode.
`text`	Text (up to 80 characters in length) that describes the neighbor.

Command Default

There is no description of the neighbor.

Command Modes

Router configuration (config-router) Address family configuration (config-router-af)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Examples

In the following examples, the description of the neighbor is “peer with example.com”:


Device(config)#router bgp 109
Device(config-router)#network 172.16.0.0
Device(config-router)#neighbor 172.16.2.3 description peer with example.com

In the following example, the description of the address family neighbor is “address-family-peer”:


Device(config)#router eigrp virtual-name
Device(config-router)#address-family ipv4 autonomous-system 4453
Device(config-router-af)#network 172.16.0.0
Device(config-router-af)#neighbor 172.16.2.3 description address-family-peer

Related Commands


Command	Description
address-family (EIGRP)	Enters address family configuration mode to configure an EIGRP routing instance.
network (EIGRP)	Specifies the network for an EIGRP routing process.
router eigrp	Configures the EIGRP address family process.

network (EIGRP)

To specify the network for an Enhanced Interior Gateway Routing Protocol (EIGRP) routing process, use the network command in router configuration mode or address-family configuration mode. To remove an entry, use the no form of this command.

network ip-address [wildcard-mask]

no network ip-address [wildcard-mask]

Syntax Description


`ip-address`	IP address of the directly connected network.
`wildcard-mask`	(Optional) EIGRP wildcard bits. Wildcard mask indicates a subnetwork, bitwise complement of the subnet mask.

Command Default

No networks are specified.

Command Modes

Router configuration (config-router) Address-family configuration (config-router-af)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

When the network command is configured for an EIGRP routing process, the router matches one or more local interfaces. The network command matches only local interfaces that are configured with addresses that are within the same subnet as the address that has been configured with the network command. The router then establishes neighbors through the matched interfaces. There is no limit to the number of network statements (network commands) that can be configured on a router.

Use a wildcard mask as a shortcut to group networks together. A wildcard mask matches everything in the network part of an IP address with a zero. Wildcard masks target a specific host/IP address, entire network, subnet, or even a range of IP addresses.

When entered in address-family configuration mode, this command applies only to named EIGRP IPv4 configurations. Named IPv6 and Service Advertisement Framework (SAF) configurations do not support this command in address-family configuration mode.

Examples

The following example configures EIGRP autonomous system 1 and establishes neighbors through network 172.16.0.0 and 192.168.0.0:


Device(config)#router eigrp 1
Device(config-router)#network 172.16.0.0
Device(config-router)#network 192.168.0.0
Device(config-router)#network 192.168.0.0 0.0.255.255

The following example configures EIGRP address-family autonomous system 4453 and establishes neighbors through network 172.16.0.0 and 192.168.0.0:


Device(config)#router eigrp virtual-name
Device(config-router)#address-family ipv4 autonomous-system 4453
Device(config-router-af)#network 172.16.0.0
Device(config-router-af)#network 192.168.0.0

Related Commands


Command	Description
address-family (EIGRP)	Enters address-family configuration mode to configure an EIGRP routing instance.
router eigrp	Configures the EIGRP address-family process.

nsf (EIGRP)

To enable Cisco nonstop forwarding (NSF) operations for the Enhanced Interior Gateway Routing Protocol (EIGRP), use the nsf command in router configuration or address family configuration mode. To disable EIGRP NSF and to remove the EIGRP NSF configuration from the running-configuration file, use the no form of this command.

nsf

no nsf

Syntax Description

This command has no arguments or keywords.

Command Default

EIGRP NSF is disabled.

Command Modes

Router configuration (config-router)

Address family configuration (config-router-af)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

The nsf command is used to enable or disable EIGRP NSF support on an NSF-capable router. NSF is supported only on platforms that support High Availability.

Examples

The following example shows how to disable NSF:


Device#configure terminal
Device(config)#router eigrp 101 
Device(config-router)#no nsf
Device(config-router)#end

The following example shows how to enable EIGRP IPv6 NSF:


Device#configure terminal
Device(config)#router eigrp virtual-name-1
Device(config-router)#address-family ipv6 autonomous-system 10 
Device(config-router-af)#nsf 
Device(config-router-af)#end

Related Commands


Command	Description
debug eigrp address-family ipv6 notifications	Displays information about EIGRP address family IPv6 event notifications.
debug eigrp nsf	Displays notifications and information about NSF events for an EIGRP routing process.
debug ip eigrp notifications	Displays information and notifications for an EIGRP routing process.
show ip protocols	Displays the parameters and the current state of the active routing protocol process.
show ipv6 protocols	Displays the parameters and the current state of the active IPv6 routing protocol process.
timers graceful-restart purge-time	Sets the graceful-restart purge-time timer to determine how long an NSF-aware router that is running EIGRP must hold routes for an inactive peer.
timers nsf converge	Sets the maximum time that the restarting router must wait for the end-of-table notification from an NSF-capable or NSF-aware peer.
timers nsf signal	Sets the maximum time for the initial restart period.

offset-list (EIGRP)

To add an offset to incoming and outgoing metrics to routes learned via Enhanced Interior Gateway Routing Protocol (EIGRP), use the offset-list command in router configuration mode or address family topology configuration mode. To remove an offset list, use the no form of this command.

offset-list {access-list-number | access-list-name} {in | out} offset [interface-type interface-number]

no offset-list {access-list-number | access-list-name} {in | out} offset [interface-type interface-number]

Syntax Description


`access-list-number` \| `access-list-name`	Standard access list number or name to be applied. Access list number 0 indicates all networks (networks, prefixes, or routes). If the `offset` value is 0, no action is taken.
in	Applies the access list to incoming metrics.
out	Applies the access list to outgoing metrics.
`offset`	Positive offset to be applied to metrics for networks matching the access list. If the offset is 0, no action is taken.
`interface-type`	(Optional) Interface type to which the offset list is applied.
`interface-number`	(Optional) Interface number to which the offset list is applied.

Command Default

No offset values are added to incoming or outgoing metrics to routes learned via EIGRP.

Command Modes

Router configuration (config-router) Address family topology configuration (config-router-af-topology)

Command History

Table 4.
Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

The offset value is added to the routing metric. An offset list with an interface type and interface number is considered extended and takes precedence over an offset list that is not extended. Therefore, if an entry passes the extended offset list and the normal offset list, the offset of the extended offset list is added to the metric.

Examples

In the following example, the router applies an offset of 10 to the delay component of the router only to access list 21:


Device(config-router)#offset-list 21 out 10

In the following example, the router applies an offset of 10 to routes learned from Ethernet interface 0:


Device(config-router)#offset-list 21 in 10 ethernet 0

In the following example, the router applies an offset of 10 to routes learned from Ethernet interface 0 in an EIGRP named configuration:


Device(config)#router eigrp virtual-name
Device(config-router)#address-family ipv4 autonomous-system 1
Device(config-router-af)#topology base
Device(config-router-af-topology)#offset-list 21 in 10 ethernet0

redistribute (IP)

To redistribute routes from one routing domain into another routing domain, use the redistribute command in the appropriate configuration mode. To disable all or some part of the redistribution (depending on the protocol), use the no form of this command. See the “Usage Guidelines” section for detailed, protocol-specific behaviors.

redistribute protocol [process-id] {level-1 | level-1-2 | level-2} [autonomous-system-number] [metric {metric-value | transparent}] [metric-type type-value] [match {internal | external 1 | external 2}] [tag tag-value] [route-map map-tag] [subnets] [nssa-only]

no redistribute protocol [process-id] {level-1 | level-1-2 | level-2} [autonomous-system-number] [metric {metric-value | transparent}] [metric-type type-value] [match {internal | external 1 | external 2}] [tag tag-value] [route-map map-tag] [subnets] [nssa-only]

Syntax Description

protocol

Source protocol from which routes are being redistributed. It can be one of the following keywords: application , bgp , connected , eigrp , isis , mobile , ospf , rip, or static [ip ].

The static [ip ] keyword is used to redistribute IP static routes. The optional ip keyword is used when redistributing into the Intermediate System-to-Intermediate System (IS-IS) protocol.

The application keyword is used to redistribute an application from one routing domain to another. You can redistribute more than one application to different routing protocols such as IS-IS, OSPF, Border Gateway Protocol (BGP), Enhanced Interior Gateway Routing Protocol (EIGRP) and Routing Information Protocol (RIP).

The connected keyword refers to routes that are established automatically by virtue of having enabled IP on an interface. For routing protocols such as Open Shortest Path First (OSPF) and IS-IS, these routes will be redistributed as external to the autonomous system.

process-id

(Optional) For the application keyword, this is the name of an application.

For the bgp or eigrp keyword, this is an autonomous system number, which is a 16-bit decimal number.

For the isis keyword, this is an optional tag value that defines a meaningful name for a routing process. Creating a name for a routing process means that you use names when configuring routing. You can configure a router in two routing domains and redistribute routing information between these two domains.

For the ospf keyword, this is an appropriate OSPF process ID from which routes are to be redistributed. This identifies the routing process. This value takes the form of a nonzero decimal number.

For the rip keyword, no process-id value is needed.

For the application keyword, this is the name of an application.

By default, no process ID is defined.

level-1

Specifies that, for IS-IS, Level 1 routes are redistributed into other IP routing protocols independently.

level-1-2

Specifies that, for IS-IS, both Level 1 and Level 2 routes are redistributed into other IP routing protocols.

level-2

Specifies that, for IS-IS, Level 2 routes are redistributed into other IP routing protocols independently.

autonomous-system-number

(Optional) Autonomous system number for the redistributed route. The range is from 1 to 65535.

4-byte autonomous system numbers are supported in the range from 1.0 to 65535.65535 in asdot notation only.

For more details about autonomous system number formats, see the router bgp command.

metric metric-value

(Optional) When redistributing from one OSPF process to another OSPF process on the same router, the metric will be carried through from one process to the other if no metric value is specified. When redistributing other processes to an OSPF process, the default metric is 20 when no metric value is specified. The default value is 0.

metric transparent

(Optional) Causes RIP to use the routing table metric for redistributed routes as the RIP metric.

metric-type type value

(Optional) For OSPF, specifies the external link type associated with the default route advertised into the OSPF routing domain. It can be one of two values:

1 —Type 1 external route
2 —Type 2 external route

If a metric-type is not specified, the Cisco IOS software adopts a Type 2 external route.

For IS-IS, it can be one of two values:

internal —IS-IS metric that is < 63.
external —IS-IS metric that is > 64 < 128.

The default is internal .

match {internal | external1 | external2 }

(Optional) Specifies the criteria by which OSPF routes are redistributed into other routing domains. It can be one of the following:

internal —Routes that are internal to a specific autonomous system.
external 1 —Routes that are external to the autonomous system, but are imported into OSPF as Type 1 external routes.
external 2 —Routes that are external to the autonomous system, but are imported into OSPF as Type 2 external routes.

The default is internal .

tag tag-value

(Optional) Specifies the 32-bit decimal value attached to each external route. This is not used by OSPF itself. It may be used to communicate information between Autonomous System Boundary Routers (ASBRs). If none is specified, the remote autonomous system number is used for routes from BGP and Exterior Gateway Protocol (EGP); for other protocols, zero (0) is used.

route-map

(Optional) Specifies the route map that should be interrogated to filter the importation of routes from this source routing protocol to the current routing protocol. If not specified, all routes are redistributed. If this keyword is specified, but no route map tags are listed, no routes will be imported.

map-tag

(Optional) Identifier of a configured route map.

subnets

(Optional) For redistributing routes into OSPF.

Note

Irrespective of whether the subnets keyword is configured or not, the subnets functionality is enabled by default. This automatic addition results in the redistribution of classless OSPF routes.

nssa-only

(Optional) Sets the nssa-only attribute for all routes redistributed into OSPF.

Command Default

Route redistribution is disabled.

Command Modes

Router configuration (config-router)

Address family configuration (config-af)

Address family topology configuration (config-router-af-topology)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Using the no Form of the redistribute Command

Caution

Removing options that you have configured for the redistribute command requires careful use of the no form of the redistribute command to ensure that you obtain the result that you are expecting. Changing or disabling any keyword may or may not affect the state of other keywords, depending on the protocol.

It is important to understand that different protocols implement the no form of the redistribute command differently:

In BGP, OSPF, and RIP configurations, the no redistribute command removes only the specified keywords from the redistribute commands in the running configuration. They use the subtractive keyword method when redistributing from other protocols. For example, in the case of BGP, if you configure no redistribute static route-map interior , only the route map is removed from the redistribution, leaving redistribute static in place with no filter.
The no redistribute isis command removes the IS-IS redistribution from the running configuration. IS-IS removes the entire command, regardless of whether IS-IS is the redistributed or redistributing protocol.
EIGRP used the subtractive keyword method prior to EIGRP component version rel5. Starting with EIGRP component version rel5, the no redistribute command removes the entire redistribute command when redistributing from any other protocol.
An EIGRP routing process is configured when you issue the router eigrp command and then specify a network for the process using the network sub-command. Suppose that you have not configured an EIGRP routing process, and that you have configured redistribution of routes from such an EIGRP process into BGP, OSPF, or RIP. If you use the no redistribute eigrp command to change or disable a parameter in the redistribute eigrp command, the no redistribute eigrp command removes the entire redistribute eigrp command instead of changing or disabling a specific parameter.

Additional Usage Guidelines for the redistribute Command

A router receiving a link-state protocol with an internal metric will consider the cost of the route from itself to the redistributing router plus the advertised cost to reach the destination. An external metric only considers the advertised metric to reach the destination.

Routes learned from IP routing protocols can be redistributed at Level 1 into an attached area or at Level 2. The level-1-2 keyword allows both Level 1 and Level 2 routes in a single command.

Redistributed routing information must be filtered by the distribute-list out router configuration command. This guideline ensures that only those routes intended by the administrator are passed along to the receiving routing protocol.

Whenever you use the redistribute or the default-information router configuration commands to redistribute routes into an OSPF routing domain, the router automatically becomes an ASBR. However, an ASBR does not, by default, generate a default route into the OSPF routing domain.

When routes are redistributed into OSPF from protocols other than OSPF or BGP, and no metric has been specified with the metric-type keyword and type-value argument, OSPF will use 20 as the default metric. When routes are redistributed into OSPF from BGP, OSPF will use 1 as the default metric. When routes are redistributed from one OSPF process to another OSPF process, autonomous system external and not-so-stubby-area (NSSA) routes will use 20 as the default metric. When intra-area and inter-area routes are redistributed between OSPF processes, the internal OSPF metric from the redistribution source process is advertised as the external metric in the redistribution destination process. (This is the only case in which the routing table metric will be preserved when routes are redistributed into OSPF.)

Note

The show ip ospf [topology-info ] command will display subnets keyword irrespective of whether the subnets keyword is configured or not. This is because the subnets functionality is enabled by default for OSPF.

On a router internal to an NSSA area, the nssa-only keyword causes the originated type-7 NSSA LSAs to have their propagate (P) bit set to zero, which prevents area border routers from translating these LSAs into type-5 external LSAs. On an area border router that is connected to an NSSA and normal areas, the nssa-only keyword causes the routes to be redistributed only into the NSSA areas.

Routes configured with the connected keyword affected by this redistribute command are the routes not specified by the network router configuration command.

You cannot use the default-metric command to affect the metric used to advertise connected routes.

Note

The metric value specified in the redistribute command supersedes the metric value specified in the default-metric command.

The default redistribution of Interior Gateway Protocol (IGP) or Exterior Gateway Protocol (EGP) into BGP is not allowed unless the default-information originate router configuration command is specified.

4-Byte Autonomous System Number Support

The Cisco implementation of 4-byte autonomous system numbers uses asplain—65538 for example—as the default regular expression match and output display format for autonomous system numbers, but you can configure 4-byte autonomous system numbers in both the asplain format and the asdot format as described in RFC 5396. To change the default regular expression match and output display of 4-byte autonomous system numbers to asdot format, use the bgp asnotation dot command.

Examples

The following example shows how OSPF routes are redistributed into a BGP domain:


Device(config)# router bgp 109
Device(config-router)# redistribute ospf

The following example shows how to redistribute EIGRP routes into an OSPF domain:


Device(config)# router ospf 110
Device(config-router)# redistribute eigrp

The following example shows how to redistribute the specified EIGRP process routes into an OSPF domain. The EIGRP-derived metric will be remapped to 100 and RIP routes to 200.


Device(config)# router ospf 109
Device(config-router)# redistribute eigrp 108 metric 100 subnets
Device(config-router)# redistribute rip metric 200 subnets

The following example shows how to configure BGP routes to be redistributed into IS-IS. The link-state cost is specified as 5, and the metric type is set to external, indicating that it has lower priority than internal metrics.


Device(config)# router isis
Device(config-router)# redistribute bgp 120 metric 5 metric-type external

The following example shows how to redistribute an application into an OSPF domain and specify a metric value of 5:


Device(config)# router ospf 4
Device(config-router)# redistribute application am metric 5

In the following example, network 172.16.0.0 will appear as an external LSA in OSPF 1 with a cost of 100 (the cost is preserved):


Device(config)# interface ethernet 0
Device(config-if)# ip address 172.16.0.1 255.0.0.0
Device(config-if)# exit
Device(config)# ip ospf cost 100
Device(config)# interface ethernet 1
Device(config-if)# ip address 10.0.0.1 255.0.0.0
!
Device(config)# router ospf 1
Device(config-router)# network 10.0.0.0 0.255.255.255 area 0
Device(config-if)# exit
Device(config-router)# redistribute ospf 2 subnet
Device(config)# router ospf 2
Device(config-router)# network 172.16.0.0 0.255.255.255 area 0

The following example shows how BGP routes are redistributed into OSPF and assigned the local 4-byte autonomous system number in asplain format.


Device(config)# router ospf 2
Device(config-router)# redistribute bgp 65538

The following example shows how to remove the connected metric 1000 subnets options from the redistribute connected metric 1000 subnets command and leave the redistribute connected command in the configuration:


Device(config-router)# no redistribute connected metric 1000 subnets

The following example shows how to remove the metric 1000 options from the redistribute connected metric 1000 subnets command and leave the redistribute connected subnets command in the configuration:


Device(config-router)# no redistribute connected metric 1000

The following example shows how to remove the subnets option from the redistribute connected metric 1000 subnets command and leave the redistribute connected metric 1000 command in the configuration:


Device(config-router)# no redistribute connected subnets

The following example shows how to remove the redistribute connected command, and any of the options that were configured for the redistribute connected command, from the configuration:


Device(config-router)# no redistribute connected

The following example shows how EIGRP routes are redistributed into an EIGRP process in a named EIGRP configuration:


Device(config)# router eigrp virtual-name
Device(config-router)# address-family ipv4 autonomous-system 1
Device(config-router-af)# topology base
Device(config-router-af-topology)# redistribute eigrp 6473 metric 1 1 1 1 1

The following example shows how to set and disable the redistributions in EIGRP configuration. Note that, in the case of EIGRP, the no form of the commands removes the entire set of redistribute commands from the running configuration.


Device(config)# router eigrp 1
Device(config-router)# network 0.0.0.0
Device(config-router)# redistribute eigrp 2 route-map x
Device(config-router)# redistribute ospf 1 route-map x
Device(config-router)# redistribute bgp 1 route-map x
Device(config-router)# redistribute isis level-2 route-map x
Device(config-router)# redistribute rip route-map x

Device(config)# router eigrp 1
Device(config-router)# no redistribute eigrp 2 route-map x
Device(config-router)# no redistribute ospf 1 route-map x
Device(config-router)# no redistribute bgp 1 route-map x
Device(config-router)# no redistribute isis level-2 route-map x
Device(config-router)# no redistribute rip route-map x
Device(config-router)# end

Device# show running-config | section router eigrp 1

router eigrp 1
 network 0.0.0.0

The following example shows how to set and disable the redistributions in OSPF configuration. Note that the no form of the commands removes only the specified keywords from the redistribute command in the running configuration.

Device(config)# router ospf 1
Device(config-router)# network 0.0.0.0
Device(config-router)# redistribute eigrp 2 route-map x
Device(config-router)# redistribute ospf 1 route-map x
Device(config-router)# redistribute bgp 1 route-map x
Device(config-router)# redistribute isis level-2 route-map x
Device(config-router)# redistribute rip route-map x

Device(config)# router ospf 1
Device(config-router)# no redistribute eigrp 2 route-map x
Device(config-router)# no redistribute ospf 1 route-map x
Device(config-router)# no redistribute bgp 1 route-map x
Device(config-router)# no redistribute isis level-2 route-map x
Device(config-router)# no redistribute rip route-map x
Device(config-router)# end

Device# show running-config | section router ospf 1

router ospf 1
 redistribute eigrp 2
 redistribute ospf 1
 redistribute bgp 1
 redistribute rip 
 network 0.0.0.0

The following example shows how to remove only the route map filter from the redistribution in BGP; redistribution itself remains in force without a filter:

Device(config)# router bgp 65000
Device(config-router)# no redistribute eigrp 2 route-map x

The following example shows how to remove the EIGRP redistribution to BGP:

Device(config)# router bgp 65000
Device(config-router)# no redistribute eigrp 2

Related Commands


Command	Description
default-information originate (OSPF)	Generates a default route into an OSPF routing domain.
router bgp	Configures the BGP routing process.
router eigrp	Configures the EIGRP address-family process.

route-map

To define conditions for redistributing routes from one routing protocol to another routing protocol, or to enable policy routing, use the route-map command in global configuration mode. To delete an entry, use the no form of this command.

route-map map-tag [permit | deny] [sequence-number] ordering-seq sequence-name

no route-map map-tag [permit | deny] [sequence-number] ordering-seq sequence-name

Syntax Description


`map-tag`	Name for the route map.
permit	(Optional) Permits only the routes matching the route map to be forwarded or redistributed.
deny	(Optional) Blocks routes matching the route map from being forwarded or redistributed.
`sequence-number`	(Optional) Number that indicates the position a new route map will have in the list of route maps already configured with the same name.
ordering-seq `sequence-name`	(Optional) Orders the route maps based on the string provided.

Command Default

Policy routing is not enabled, and conditions for redistributing routes from one routing protocol to another routing protocol are not configured.

Command Modes

Global configuration (config)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Use the route-map command to enter route-map configuration mode.

Use route maps to redistribute routes, or to subject packets to policy routing. Both these purposes are described here.

Redistribution

Use the route-map global configuration command and the match and set route-map configuration commands to define the conditions for redistributing routes from one routing protocol to another. Each route-map command has a list of match and set commands associated with it. The match commands specify the match criteria , that is, the conditions under which redistribution is allowed for the current route-map command. The set commands specify the set actions , that is, the redistribution actions to be performed if the criteria enforced by the match commands are met. If the route-map command is enabled and the user does not specify any action, then the permit action is applied by default. The no route-map command deletes the route map.

The match route-map configuration command has multiple formats. The match commands can be run in any order, and all the match commands must match to cause the route to be redistributed according to the set actions specified with the set commands. The no forms of the match commands remove the specified match criteria.

Use route maps when you want detailed control over how routes are redistributed between routing processes. The destination routing protocol is the one you specify with the router global configuration command. The source routing protocol is the one you specify with the redistribute router configuration command. See the examples section for an illustration of how route maps are configured.

When passing routes through a route map, the route map can have several parts. Any route that does not match at least one match clause relating to a route-map command is ignored, that is, the route is not advertised for outbound route maps, and is not accepted for inbound route maps. If you want to modify only some data, configure a second route map section with an explicit match specified.

The redistribute router configuration command uses the name specified by the map-tag argument to reference a route map. Multiple route maps can share the same map tag name.

If the match criteria are met for this route map, and the permit keyword is specified, the route is redistributed as controlled by the set actions. In the case of policy routing, the packet is policy routed. If the match criteria are not met, and the permit keyword is specified, the next route map with the same map tag is tested. If a route passes none of the match criteria for the set of route maps sharing the same name, it is not redistributed by that set.

If the match criteria are met for the route map, and the deny keyword is specified, the route is not redistributed. In the case of policy routing, the packet is not policy routed, and no other route maps sharing the same map tag name are examined. If the packet is not policy routed, the normal forwarding algorithm is used.

Policy Routing

Another purpose of route maps is to enable policy routing. Use the ip policy route-map or ipv6 policy route-map command in addition to the route-map command, and the match and set commands to define the conditions for policy-routing packets. The match commands specify the conditions under which policy routing occurs. The set commands specify the routing actions to be performed if the criteria enforced by the match commands are met. We recommend that you policy route packets some way other than the obvious shortest path.

The sequence-number argument works as follows:

If no entry is defined with the supplied tag, an entry is created with the sequence-number argument set to 10.
If only one entry is defined with the supplied tag, that entry becomes the default entry for the route-map command. The sequence-number argument of this entry is unchanged.
If more than one entry is defined with the supplied tag, an error message is displayed to indicate that the sequence-number argument is required.

If the no route-map map-tag command is specified (without the sequence-number argument), the entire route map is deleted.

Examples

The following example shows how to redistribute Routing Information Protocol (RIP) routes with a hop count equal to 1 to the Open Shortest Path First (OSPF). These routes will be redistributed to the OSPF as external link-state advertisements (LSAs) with a metric of 5, metric type of type1, and a tag equal to 1.

Device> enable
Device# configure terminal
Device(config)# router ospf 109
Device(config-router)# redistribute rip route-map rip-to-ospf
Device(config-router)# exit
Device(config)# route-map rip-to-ospf permit
Device(config-route-map)# match metric 1
Device(config-route-map)# set metric 5
Device(config-route-map)# set metric-type type1
Device(config-route-map)# set tag 1

The following example for IPv6 shows how to redistribute RIP routes with a hop count equal to 1 to the OSPF. These routes will be redistributed to the OSPF as external LSAs, with a tag equal to 42, and a metric type equal to type1.

Device> enable
Device# configure terminal
Device(config)# ipv6 router ospf 1
Device(config-router)# redistribute rip one route-map rip-to-ospfv3
Device(config-router)# exit
Device(config)# route-map rip-to-ospfv3
Device(config-route-map)# match tag 42
Device(config-route-map)# set metric-type type1

The following named configuration example shows how to redistribute Enhanced Interior Gateway Routing Protocol (EIGRP) addresses with a hop count equal to 1. These addresses are redistributed to the EIGRP as external, with a metric of 5, and a tag equal to 1:

Device> enable
Device# configure terminal
Device(config)# router eigrp virtual-name1
Device(config-router)# address-family ipv4 autonomous-system 4453
Device(config-router-af)# topology base
Device(config-router-af-topology)# redistribute eigrp 6473 route-map virtual-name1-to-virtual-name2
Device(config-router-af-topology)# exit-address-topology
Device(config-router-af)# exit-address-family
Device(config-router)# router eigrp virtual-name2
Device(config-router)# address-family ipv4 autonomous-system 6473
Device(config-router-af)# topology base
Device(config-router-af-topology)# exit-af-topology
Device(config-router-af)# exit-address-family
Device(config)# route-map virtual-name1-to-virtual-name2
Device(config-route-map)# match tag 42
Device(config-route-map)# set metric 5
Device(config-route-map)# set tag 1

Related Commands


Command	Description
ip policy route-map	Identifies a route map to use for policy routing on an interface.
ipv6 policy route-map	Configures IPv6 PBR on an interface.
match	Matches values from the routing table.
router eigrp	Configures the EIGRP address-family process.
set	Sets values in the destination routing protocol
show route-map	Displays all route maps configured or only the one specified.

router-id

To use a fixed router ID, use the router-id command in router configuration mode. To force Open Shortest Path First (OSPF) to use the previous OSPF router ID behavior, use the no form of this command.

router-id ip-address

no router-id ip-address

Syntax Description


`ip-address`	Router ID in IP address format.

Command Default

No OSPF routing process is defined.

Command Modes

Router configuration

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

You can configure an arbitrary value in the IP address format for each router. However, each router ID must be unique.

If this command is used on an OSPF router process which is already active (has neighbors), the new router-ID is used at the next reload or at a manual OSPF process restart. To manually restart the OSPF process, use the clear ip ospf command.

Examples

The following example specifies a fixed router-id:


router-id 10.1.1.1

Related Commands


Command	Description
clear ip ospf	Clears redistribution based on the OSPF routing process ID.
router ospf	Configures the OSPF routing process.

router eigrp

To configure the EIGRP routing process, use the router eigrp command in global configuration mode. To remove an EIGRP routing process, use the no form of this command.

router eigrp {autonomous-system-number | virtual-instance-name}

no router eigrp {autonomous-system-number | virtual-instance-name}

Syntax Description


`autonomous-system-number`	Autonomous system number that identifies the services to the other EIGRP address-family routers. It is also used to tag routing information. Valid range is 1 to 65535.
`virtual-instance-name`	EIGRP virtual instance name. This name must be unique among all address-family router processes on a single router, but need not be unique among routers.

Command Default

No EIGRP processes are configured.

Command Modes

Global configuration (config)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Configuring the router eigrp command with the autonomous-system-number argument creates an EIGRP configuration referred to as autonomous system (AS) configuration. An EIGRP AS configuration creates an EIGRP routing instance that can be used for tagging routing information.

Configuring the router eigrp command with the virtual-instance-name argument creates an EIGRP configuration referred to as EIGRP named configuration. An EIGRP named configuration does not create an EIGRP routing instance by itself. An EIGRP named configuration is a base configuration that is required to define address-family configurations under it that are used for routing.

Examples

The following example configures EIGRP process 109:

Device(config)# router eigrp 109

The following example configures an EIGRP address-family routing process and assigns it the name virtual-name:

Device(config)# router eigrp virtual-name

router ospf

To configure an OSPF routing process, use the router ospf command in global configuration mode. To terminate an OSPF routing process, use the no form of this command.

router ospf process-id [vrf vrf-name]

no router ospf process-id [vrf vrf-name]

Syntax Description


`process-id`	Internally used identification parameter for an OSPF routing process. It is locally assigned and can be any positive integer. A unique value is assigned for each OSPF routing process.
vrf `vrf-name`	(Optional) Specifies the name of the VPN routing and forwarding (VRF) instance to associate with OSPF VRF processes.

Command Default

No OSPF routing process is defined.

Command Modes

Global configuration

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

You can specify multiple OSPF routing processes in each router.

After you enter the router ospf command, you can enter the maximum number of paths. There can be from 1 to 32 paths.

Examples

The following example configures an OSPF routing process and assign a process number of 109:

Device(config)# router ospf 109

This example shows a basic OSPF configuration using the router ospf command to configure OSPF VRF instance processes for the VRFs first, second, and third:

Device> enable
Device# configure terminal
Device(config)# router ospf 12 vrf first
Device(config)# router ospf 13 vrf second
Device(config)# router ospf 14 vrf third
Device(config)# exit

The following example shows usage of the maximum-paths option:

Device> enable
Device# configure terminal
Device(config)# router ospf
Device(config-router)# maximum-paths 2
Device(config-router)# exit

Related Commands


Command	Description
network area	Defines the interfaces on which OSPF runs and defines the area ID for those interfaces.

send-lifetime

To set the time period during which an authentication key on a key chain is valid to be sent, use the send-lifetime command in key chain key configuration mode. To revert to the default value, use the no form of this command.

send-lifetime [ local ] start-time { infinite | end-time | duration seconds }

no send-lifetime

Syntax Description


local	Specifies the time in local timezone.
`start-time`	Beginning time that the key specified by the key command is valid to be sent. The syntax can be either of the following: `hh` : `mm` : `ss` `month` `date` `year` `hh` : `mm` : `ss` `date` `month` `year` `hh` : Hours `mm` : Minutes `ss` : Seconds `month` : First three letters of the month `date` : Date (1-31) `year` : Year (four digits) The default start time and the earliest acceptable date is January 1, 1993.
infinite	Key is valid to be sent from the `start-time` value on.
`end-time`	Key is valid to be sent from the `start-time` value until the `end-time` value. The syntax is the same as that for the `start-time` value`.` The `end-time` value must be after the `start-time` value. The default end time is an infinite time period.
duration `seconds`	Length of time (in seconds) that the key is valid to be sent. The range is from 1 to 864000.

Command Default

Forever (the starting time is January 1, 1993, and the ending time is infinite)

Command Modes

Key chain key configuration (config-keychain-key)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Specify a start-time value and one of the following values: infinite , end-time , or duration seconds .

We recommend running Network Time Protocol (NTP) or some other time synchronization method if you intend to set lifetimes on keys.

If the last key expires, authentication will continue and an error message will be generated. To disable authentication, you must manually delete the last valid key.

Examples

The following example configures a key chain named chain1. The key named key1 will be accepted from 1:30 p.m. to 3:30 p.m. and be sent from 2:00 p.m. to 3:00 p.m. The key named key2 will be accepted from 2:30 p.m. to 4:30 p.m. and be sent from 3:00 p.m. to 4:00 p.m. The overlap allows for migration of keys or a discrepancy in the set time of the router. There is a 30-minute leeway on each side to handle time differences.

Device(config)# interface GigabitEthernet1/0/1
Device(config-if)# ip rip authentication key-chain chain1
Device(config-if)# ip rip authentication mode md5
Device(config-if)# exit
Device(config)# router rip
Device(config-router)# network 172.19.0.0
Device(config-router)# version 2
Device(config-router)# exit
Device(config)# key chain chain1
Device(config-keychain)# key 1
Device(config-keychain-key)# key-string key1
Device(config-keychain-key)# accept-lifetime 13:30:00 Jan 25 1996 duration 7200
Device(config-keychain-key)# send-lifetime 14:00:00 Jan 25 1996 duration 3600
Device(config-keychain-key)# exit
Device(config-keychain)# key 2
Device(config-keychain)# key-string key2
Device(config-keychain)# accept-lifetime 14:30:00 Jan 25 1996 duration 7200
Device(config-keychain)# send-lifetime 15:00:00 Jan 25 1996 duration 3600

The following example configures a key chain named chain1 for EIGRP address-family. The key named key1 will be accepted from 1:30 p.m. to 3:30 p.m. and be sent from 2:00 p.m. to 3:00 p.m. The key named key2 will be accepted from 2:30 p.m. to 4:30 p.m. and be sent from 3:00 p.m. to 4:00 p.m. The overlap allows for migration of keys or a discrepancy in the set time of the router. There is a 30-minute leeway on each side to handle time differences.

Device(config)# router eigrp 10
Device(config-router)# address-family ipv4 autonomous-system 4453
Device(config-router-af)# network 10.0.0.0
Device(config-router-af)# af-interface ethernet0/0
Device(config-router-af-interface)# authentication key-chain trees
Device(config-router-af-interface)# authentication mode md5
Device(config-router-af-interface)# exit
Device(config-router-af)# exit
Device(config-router)# exit
Device(config)# key chain chain1
Device(config-keychain)# key 1
Device(config-keychain-key)# key-string key1
Device(config-keychain-key)# accept-lifetime 13:30:00 Jan 25 1996 duration 7200
Device(config-keychain-key)# send-lifetime 14:00:00 Jan 25 1996 duration 3600
Device(config-keychain-key)# exit
Device(config-keychain)# key 2
Device(config-keychain-key)# key-string key2
Device(config-keychain-key)# accept-lifetime 14:30:00 Jan 25 1996 duration 7200
Device(config-keychain-key)# send-lifetime 15:00:00 Jan 25 1996 duration 3600

Related Commands


Command	Description
accept-lifetime	Sets the time period during which the authentication key on a key chain is received as valid.
key	Identifies an authentication key on a key chain.
key chain	Defines an authentication key chain needed to enable authentication for routing protocols.
key-string (authentication)	Specifies the authentication string for a key.
show key chain	Displays authentication key information.

show ip eigrp interfaces

To display information about interfaces that are configured for the Enhanced Interior Gateway Routing Protocol (EIGRP), use the show ip eigrp interfaces command in user EXEC or privileged EXEC mode.

show ip eigrp [vrf vrf-name] [autonomous-system-number] interfaces [type number] [detail]

Syntax Description


vrf `vrf-name`	(Optional) Displays information about the specified virtual routing and forwarding (VRF) instance.
`autonomous-system-number`	(Optional) Autonomous system number whose output needs to be filtered.
`type`	(Optional) Interface type. For more information, use the question mark (?) online help function.
`number`	(Optional) Interface or subinterface number. For more information about the numbering syntax for your networking device, use the question mark (?) online help function.
detail	(Optional) Displays detailed information about EIGRP interfaces for a specific EIGRP process.

Command Modes

User EXEC (>)

Privileged EXEC (#)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

Use the show ip eigrp interfaces command to display active EIGRP interfaces and EIGRP-specific interface settings and statistics. The optional type number argument and the detail keyword can be entered in any order.

If an interface is specified, only information about that interface is displayed. Otherwise, information about all interfaces on which EIGRP is running is displayed.

If an autonomous system is specified, only the routing process for the specified autonomous system is displayed. Otherwise, all EIGRP processes are displayed.

This command can be used to display information about EIGRP named and EIGRP autonomous system configurations.

This command displays the same information as the show eigrp address-family interfaces command. Cisco recommends using the show eigrp address-family interfaces command.

Examples

The following is sample output from the show ip eigrp interfaces command:


Device#show ip eigrp interfaces

EIGRP-IPv4 Interfaces for AS(60)
                    Xmit Queue    Mean   Pacing Time   Multicast   Pending
Interface   Peers   Un/Reliable   SRTT   Un/Reliable   Flow Timer  Routes
Di0           0         0/0          0      11/434          0          0
Et0           1         0/0        337       0/10           0          0
SE0:1.16      1         0/0         10       1/63         103          0
Tu0           1         0/0        330       0/16           0          0

The following sample output from the show ip eigrp interfaces detail command displays detailed information about all active EIGRP interfaces:


Device#show ip eigrp interfaces detail

EIGRP-IPv4 Interfaces for AS(1)
                        Xmit Queue   PeerQ        Mean   Pacing Time   Multicast   Pending 
Interface        Peers  Un/Reliable  Un/Reliable  SRTT   Un/Reliable   Flow Timer   Routes
Et0/0              1        0/0       0/0         525       0/2         3264           0
Hello-interval is 5, Hold-time is 15
  Split-horizon is enabled
  Next xmit serial <none>
  Packetized sent/expedited: 3/0
  Hello's sent/expedited: 6/2
  Un/reliable mcasts: 0/6  Un/reliable ucasts: 7/4
  Mcast exceptions: 1  CR packets: 1  ACKs suppressed: 0
  Retransmissions sent: 1  Out-of-sequence rcvd: 0
  Topology-ids on interface - 0 
  Authentication mode is not set

The following sample output from the show ip eigrp interfaces detail command displays detailed information about a specific interface on which the no ip next-hop self command is configured along with the no-ecmp-mode option:


Device#show ip eigrp interfaces detail tunnel 0

EIGRP-IPv4 Interfaces for AS(1)
                        Xmit Queue   PeerQ        Mean   Pacing Time   Multicast   Pending 
Interface        Peers  Un/Reliable  Un/Reliable  SRTT   Un/Reliable   Flow Timer   Routes
Tu0/0              2        0/0       0/0         		2       0/0         50           0
Hello-interval is 5, Hold-time is 15
  Split-horizon is disabled
  Next xmit serial <none>
  Packetized sent/expedited: 24/3
  Hello's sent/expedited: 28083/9
  Un/reliable mcasts: 0/19  Un/reliable ucasts: 18/64
  Mcast exceptions: 5  CR packets: 5  ACKs suppressed: 0
  Retransmissions sent: 52  Out-of-sequence rcvd: 2
		Next-hop-self disabled, next-hop info forwarded, ECMP mode Enabled
  Topology-ids on interface - 0 
  Authentication mode is not set

The table below describes the significant fields shown in the displays.

Table 5. show ip eigrp interfaces Field Descriptions
Field	Description
Interface	Interface on which EIGRP is configured.
Peers	Number of directly connected EIGRP neighbors.
PeerQ Un/Reliable	Number of unreliable and reliable packets queued for transmission to specific peers on the interface.
Xmit Queue Un/Reliable	Number of packets remaining in the Unreliable and Reliable transmit queues.
Mean SRTT	Mean smooth round-trip time (SRTT) interval (in seconds).
Pacing Time Un/Reliable	Pacing time (in seconds) used to determine when EIGRP packets (unreliable and reliable) should be sent out of the interface .
Multicast Flow Timer	Maximum number of seconds for which the device will send multicast EIGRP packets.
Pending Routes	Number of routes in the transmit queue waiting to be sent.
Packetized sent/expedited	Number of EIGRP routes that have been prepared for sending packets to neighbors on an interface, and the number of times multiple routes were stored in a single packet.
Hello’s sent/expedited	Number of EIGRP hello packets that have been sent on an interface and packets that were expedited.

Related Commands


Command	Description
show eigrp address-family interfaces	Displays information about address family interfaces configured for EIGRP.
show ip eigrp neighbors	Displays neighbors discovered by EIGRP.

show ip eigrp neighbors

To display neighbors discovered by the Enhanced Interior Gateway Routing Protocol (EIGRP), use the show ip eigrp neighbors command in privileged EXEC mode.

show ip eigrp [vrf vrf-name] [autonomous-system-number] neighbors [static | detail] [interface-type interface-number]

Syntax Description


vrf `vrf-name`	(Optional) Displays information about the specified VPN Routing and Forwarding (VRF) instance.
`autonomous-system-number`	(Optional) Autonomous-system-number-specific output is displayed.
static	(Optional) Displays static neighbors.
detail	(Optional) Displays detailed neighbor information.
`interface-type` `interface-number`	(Optional) Interface-specific output is displayed.

Command Modes

Privileged EXEC (#)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

The show ip eigrp neighbors command can be used to display information about EIGRP named and EIGRP autonomous-system configurations. Use the show ip eigrp neighbors command to display dynamic and static neighbor states. You can use this command for also debugging certain types of transport problems.

This command displays the same information as the show eigrp address-family neighbors command. Cisco recommends that you use the show eigrp address-family neighbors command.

Examples

The following is sample output from the show ip eigrp neighbors command:


Device#show ip eigrp neighbors

H   Address                 Interface       Hold Uptime   SRTT   RTO  Q  Seq
                                            (sec)         (ms)       Cnt Num
0   10.1.1.2                 Et0/0             13 00:00:03 1996  5000  0  5
2   10.1.1.9                 Et0/0             14 00:02:24 206   5000  0  5
1   10.1.2.3                 Et0/1             11 00:20:39 2202  5000  0  5

The table below describes the significant fields shown in the display.

Table 6. show ip eigrp neighbors Field Descriptions
Field	Description
Address	IP address of the EIGRP peer.
Interface	Interface on which the router is receiving hello packets from the peer.
Hold	Time in seconds for which EIGRP waits to hear from the peer before declaring it down.
Uptime	Elapsed time (in hours:minutes: seconds) since the local router first heard from this neighbor.
SRTT	Smooth round-trip time. This is the number of milliseconds required for an EIGRP packet to be sent to this neighbor and for the local router to receive an acknowledgment of that packet.
RTO	Retransmission timeout (in milliseconds). This is the amount of time the software waits before resending a packet from the retransmission queue to a neighbor.
Q Cnt	Number of EIGRP packets (update, query, and reply) that the software is waiting to send.
Seq Num	Sequence number of the last update, query, or reply packet that was received from this neighbor.

The following is sample output from the show ip eigrp neighbors detail command:


Device#show ip eigrp neighbors detail

EIGRP-IPv4 VR(foo) Address-Family Neighbors for AS(1)
H   Address                 Interface       Hold Uptime   SRTT   RTO  Q  Seq
                                            (sec)         (ms)       Cnt Num
0   192.168.10.1                 Gi2/0             12 00:00:21 1600  5000  0  3
   Static neighbor (Lisp Encap)
			Version 8.0/2.0, Retrans: 0, Retries: 0, Prefixes: 1
   Topology-ids from peer - 0

The table below describes the significant fields shown in the display.

Table 7. show ip eigrp neighbors detail Field Descriptions
Field	Description
H	This column lists the order in which a peering session was established with the specified neighbor. The order is specified with sequential numbering starting with 0.
Address	IP address of the EIGRP peer.
Interface	Interface on which the router is receiving hello packets from the peer.
Hold	Time in seconds for which EIGRP waits to hear from the peer before declaring it down.
Lisp Encap	Indicates that routes from this neighbor are LISP encapsulated.
Uptime	Elapsed time (in hours:minutes: seconds) since the local router first heard from this neighbor.
SRTT	Smooth round-trip time. This is the number of milliseconds required for an EIGRP packet to be sent to this neighbor and for the local router to receive an acknowledgment of that packet.
RTO	Retransmission timeout (in milliseconds). This is the amount of time the software waits before resending a packet from the retransmission queue to a neighbor.
Q Cnt	Number of EIGRP packets (update, query, and reply) that the software is waiting to send.
Seq Num	Sequence number of the last update, query, or reply packet that was received from this neighbor.
Version	The software version that the specified peer is running.
Retrans	Number of times that a packet has been retransmitted.
Retries	Number of times an attempt was made to retransmit a packet.

Related Commands


Command	Description
show eigrp address-family neighbors	Displays neighbors discovered by EIGRP.

show ip eigrp topology

To display Enhanced Interior Gateway Routing Protocol (EIGRP) topology table entries, use the show ip eigrp topology command in user EXEC or privileged EXEC mode.

Syntax Description


`network`	(Optional) Network address.
`mask`	(Optional) Network mask.
`prefix`	(Optional) Network prefix in the format <network>/<length>; for example, 192.168.0.0/16.
active	(Optional) Displays all topology entries that are in the active state.
all-links	(Optional) Displays all entries in the EIGRP topology table (including nonfeasible-successor sources).
detail-links	(Optional) Displays all topology entries with additional details.
frr	(Optional) Displays the list of configured loop-free alternates in the EIGRP topology table.
pending	(Optional) Displays all entries in the EIGRP topology table that are either waiting for an update from a neighbor or waiting to reply to a neighbor.
secondary-paths	(Optional) Displays secondary paths in the topology.
summary	(Optional) Displays a summary of the EIGRP topology table.
zero-successors	(Optional) Displays available routes that have zero successors.

Command Default

If this command is used without any of the optional keywords, only topology entries with feasible successors are displayed and only feasible paths are shown.

Command Modes

User EXEC (>)

Privileged EXEC (#)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.
Cisco IOS XE Amsterdam 17.2.1	The frr keyword was introduced.

Usage Guidelines

Use the show ip eigrp topology command to display topology entries, feasible and nonfeasible paths, metrics, and states. This command can be used without any arguments or keywords to display only topology entries with feasible successors and feasible paths. The all-links keyword displays all paths, whether feasible or not, and the detail-links keyword displays additional details about these paths.

Use this command to display information about EIGRP named and EIGRP autonomous system configurations. This command displays the same information as the show eigrp address-family topology command. We recommend using the show eigrp address-family topology command.

Examples

The following is sample output from the show ip eigrp topology command:

Device# show ip eigrp topology

EIGRP-IPv4 Topology Table for AS(1)/ID(10.0.0.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
       r - Reply status, s - sia status
P 10.0.0.0/8, 1 successors, FD is 409600
        via 192.0.2.1 (409600/128256), Ethernet0/0
P 192.16.1.0/24, 1 successors, FD is 409600
        via 192.0.2.1 (409600/128256), Ethernet0/0
P 10.0.0.0/8, 1 successors, FD is 281600
        via Summary (281600/0), Null0
P 10.0.1.0/24, 1 successors, FD is 281600
        via Connected, Ethernet0/0

The following sample output from the show ip eigrp topology prefix command displays detailed information about a single prefix. The prefix shown is an EIGRP internal route.

Device# show ip eigrp topology 10.0.0.0/8  
 
EIGRP-IPv4 VR(vr1) Topology Entry for AS(1)/ID(10.1.1.2) for 10.0.0.0/8
  State is Passive, Query origin flag is 1, 1 Successor(s), FD is 82329600, RIB is 643200
  Descriptor Blocks:
  10.1.1.1 (Ethernet2/0), from 10.1.1.1, Send flag is 0x0
      Composite metric is (82329600/163840), route is Internal
      Vector metric:
        Minimum bandwidth is 16000 Kbit
        Total delay is 631250000 picoseconds
        Reliability is 255/255
        Load is ½55
        Minimum MTU is 1500
        Hop count is 1
        Originating router is 10.1.1.1

The following sample output from the show ip eigrp topology prefix command displays detailed information about a single prefix. The prefix shown is an EIGRP external route.

Device# show ip eigrp topology 192.16.1.0/24

EIGRP-IPv4 Topology Entry for AS(1)/ID(10.0.0.1) for 192.16.1.0/24
State is Passive, Query origin flag is 1, 1 Successor(s), FD is 409600, RIB is 643200
  Descriptor Blocks:
  172.16.1.0/24 (Ethernet0/0), from 10.0.1.2, Send flag is 0x0
      Composite metric is (409600/128256), route is External
      Vector metric:
        Minimum bandwidth is 10000 Kbit
        Total delay is 6000 picoseconds
        Reliability is 255/255
        Load is ½55
        Minimum MTU is 1500
        Hop count is 1
        Originating router is 192.16.1.0/24
								External data:
        AS number of route is 0
        External protocol is Connected, external metric is 0
        Administrator tag is 0 (0x00000000)

The following sample output from the show ip eigrp topology prefix command displays Equal Cost Multipath (ECMP) mode information when the no ip next-hop-self command is configured without the no-ecmp-mode keyword in an EIGRP topology. The ECMP mode provides information about the path that is being advertised. If there is more than one successor, the top most path will be advertised as the default path over all interfaces, and “ECMP Mode: Advertise by default” will be displayed in the output. If any path other than the default path is advertised, “ECMP Mode: Advertise out <Interface name>” will be displayed.

The topology table displays entries of routes for a particular prefix. The routes are sorted based on metric, next-hop, and infosource. In a Dynamic Multipoint VPN (DMVPN) scenario, routes with same metric and next-hop are sorted based on infosource. The top route in the ECMP is always advertised.

Device# show ip eigrp topology 192.168.10.0/24

EIGRP-IPv4 Topology Entry for AS(1)/ID(10.10.100.100) for 192.168.10.0/24
State is Passive, Query origin flag is 1, 2 Successor(s), FD is 284160
  Descriptor Blocks:
  10.100.1.0 (Tunnel0), from 10.100.0.1, Send flag is 0x0
      Composite metric is (284160/281600), route is Internal
      Vector metric:
        Minimum bandwidth is 10000 Kbit
        Total delay is 1100 microseconds
        Reliability is 255/255
        Load is ½55
        Minimum MTU is 1400
        Hop count is 1
        Originating router is 10.10.1.1
								ECMP Mode: Advertise by default
        10.100.0.2 (Tunnel1), from 10.100.0.2, Send flag is 0X0
								Composite metric is (284160/281600), route is Internal
								Vector metric:
								Minimum bandwidth is 10000 Kbit
								Total delay is 1100 microseconds
								Reliability is 255/255
								Load is ½55
								Minimum MTU is 1400
								Hop count is 1
								Originating router is 10.10.2.2
								ECMP Mode: Advertise out Tunnel1

The following sample output from the show ip eigrp topology all-links command displays all paths, even those that are not feasible:

Device# show ip eigrp topology all-links

EIGRP-IPv4 Topology Table for AS(1)/ID(10.0.0.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
       r - reply Status, s - sia Status 
P 172.16.1.0/24, 1 successors, FD is 409600, serno 14
        via 10.10.1.2 (409600/128256), Ethernet0/0
        via 10.1.4.3 (2586111744/2585599744), Serial3/0, serno 18

The following sample output from the show ip eigrp topology detail-links command displays additional details about routes:

Device# show ip eigrp topology detail-links 

EIGRP-IPv4 Topology Table for AS(1)/ID(10.0.0.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
       r - reply Status, s - sia Status 
P 10.0.0.0/8, 1 successors, FD is 409600, serno 6
        via 10.10.1.2 (409600/128256), Ethernet0/0
P 172.16.1.0/24, 1 successors, FD is 409600, serno 14
        via 10.10.1.2 (409600/128256), Ethernet0/0
P 10.0.0.0/8, 1 successors, FD is 281600, serno 3
        via Summary (281600/0), Null0
P 10.1.1.0/24, 1 successors, FD is 281600, serno 1
        via Connected, Ethernet0/0

The table below describes the significant fields shown in the displays.

Table 8. show ip eigrp topology Field Descriptions
Field	Description
Codes	State of this topology table entry. Passive and Active refer to the EIGRP state with respect to the destination. Update, Query, and Reply refer to the type of packet that is being sent. P - Passive: Indicates that no EIGRP computations are being performed for this route. A - Active: Indicates that EIGRP computations are being performed for this route. U - Update: Indicates that a pending update packet is waiting to be sent for this route. Q - Query: Indicates that a pending query packet is waiting to be sent for this route. R - Reply: Indicates that a pending reply packet is waiting to be sent for this route. r - Reply status: Indicates that EIGRP has sent a query for the route and is waiting for a reply from the specified path. s - sia status: Indicates that the EIGRP query packet is in stuck-in-active (SIA) status.
successors	Number of successors. This number corresponds to the number of next hops in the IP routing table. If successors is capitalized, then the route or the next hop is in a transition state.
serno	Serial number.
FD	Feasible distance. The feasible distance is the best metric to reach the destination or the best metric that was known when the route became active. This value is used in the feasibility condition check. If the reported distance of the device is less than the feasible distance, the feasibility condition is met and that route becomes a feasible successor. After the software determines that it has a feasible successor, the software need not send a query for that destination.
via	Next-hop address that advertises the passive route.

Related Commands


Command	Description
show eigrp address-family topology	Displays entries in the EIGRP address-family topology table.

show ip eigrp traffic

To display the number of Enhanced Interior Gateway Routing Protocol (EIGRP) packets sent and received, use the show ip eigrp traffic command in privileged EXEC mode.

show ip eigrp [vrf {vrf-name | *}] [autonomous-system-number] traffic

Syntax Description


vrf `vrf-name`	(Optional) Displays information about the specified VRF.
vrf *	(Optional) Displays information about all VRFs.
`autonomous-system-number`	(Optional) Autonomous system number.

Command Modes

Privileged EXEC (#)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

This command can be used to display information about EIGRP named configurations and EIGRP autonomous-system (AS) configurations.

This command displays the same information as the show eigrp address-family traffic command. Cisco recommends using the show eigrp address-family traffic command.

Examples

The following is sample output from the show ip eigrp traffic command:


Device#show ip eigrp traffic
EIGRP-IPv4 Traffic Statistics for AS(60)
Hellos sent/received: 21429/2809
Updates sent/received: 22/17
Queries sent/received: 0/0
Replies sent/received: 0/0
Acks sent/received: 16/13
SIA-Queries sent/received: 0/0
SIA-Replies sent/received: 0/0
Hello Process ID: 204
PDM Process ID: 203
Socket Queue: 0/2000/2/0 (current/max/highest/drops)
Input Queue: 0/2000/2/0 (current/max/highest/drops)

The table below describes the significant fields shown in the display.

Table 9. show ip eigrp traffic Field Descriptions
Field	Description
Hellos sent/received	Number of hello packets sent and received.
Updates sent/received	Number of update packets sent and received.
Queries sent/received	Number of query packets sent and received.
Replies sent/received	Number of reply packets sent and received.
Acks sent/received	Number of acknowledgement packets sent and received.
SIA-Queries sent/received	Number of stuck in active query packets sent and received.
SIA-Replies sent/received	Number of stuck in active reply packets sent and received.
Hello Process ID	Hello process identifier.
PDM Process ID	Protocol-dependent module IOS process identifier.
Socket Queue	The IP to EIGRP Hello Process socket queue counters.
Input queue	The EIGRP Hello Process to EIGRP PDM socket queue counters.

Related Commands


Command	Description
show eigrp address-family traffic	Displays the number of EIGRP packets sent and received.

show ip ospf

To display general information about Open Shortest Path First (OSPF) routing processes, use the showipospf command in user EXEC or privileged EXEC mode.

show ip ospf [process-id]

Syntax Description


`process-id`	(Optional) Process ID. If this argument is included, only information for the specified routing process is included.

Command Modes

User EXEC Privileged EXEC

Command History


Mainline Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Examples

The following is sample output from the showipospf command when entered without a specific OSPF process ID:


Device#show ip ospf
 
  Routing Process "ospf 201" with ID 10.0.0.1 and Domain ID 10.20.0.1 
  Supports only single TOS(TOS0) routes 
  Supports opaque LSA 
  SPF schedule delay 5 secs, Hold time between two SPFs 10 secs 
  Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs 
  LSA group pacing timer 100 secs 
  Interface flood pacing timer 55 msecs 
  Retransmission pacing timer 100 msecs 
  Number of external LSA 0. Checksum Sum 0x0      
  Number of opaque AS LSA 0. Checksum Sum 0x0      
  Number of DCbitless external and opaque AS LSA 0 
  Number of DoNotAge external and opaque AS LSA 0 
  Number of areas in this router is 2. 2 normal 0 stub 0 nssa 
  External flood list length 0 
     Area BACKBONE(0) 
         Number of interfaces in this area is 2 
         Area has message digest authentication 
         SPF algorithm executed 4 times 
         Area ranges are 
         Number of LSA 4. Checksum Sum 0x29BEB  
         Number of opaque link LSA 0. Checksum Sum 0x0      
         Number of DCbitless LSA 3 
         Number of indication LSA 0 
         Number of DoNotAge LSA 0 
         Flood list length 0 
     Area 172.16.26.0 
         Number of interfaces in this area is 0 
         Area has no authentication 
         SPF algorithm executed 1 times 
         Area ranges are 
            192.168.0.0/16 Passive Advertise  
         Number of LSA 1. Checksum Sum 0x44FD   
         Number of opaque link LSA 0. Checksum Sum 0x0      
         Number of DCbitless LSA 1 
         Number of indication LSA 1 
         Number of DoNotAge LSA 0 
         Flood list length 0

Examples

The following is sample output from the showipospf command to verify that the BFD feature has been enabled for OSPF process 123. The relevant command output is shown in bold in the output.


Device#show ip ospf
 
 Routing Process "ospf 123" with ID 172.16.10.1
 Supports only single TOS(TOS0) routes
 Supports opaque LSA
 Supports Link-local Signaling (LLS)
 Initial SPF schedule delay 5000 msecs
 Minimum hold time between two consecutive SPFs 10000 msecs
 Maximum wait time between two consecutive SPFs 10000 msecs
 Incremental-SPF disabled
 Minimum LSA interval 5 secs
 Minimum LSA arrival 1000 msecs
 LSA group pacing timer 240 secs
 Interface flood pacing timer 33 msecs
 Retransmission pacing timer 66 msecs
 Number of external LSA 0. Checksum Sum 0x000000
 Number of opaque AS LSA 0. Checksum Sum 0x000000
 Number of DCbitless external and opaque AS LSA 0
 Number of DoNotAge external and opaque AS LSA 0
 Number of areas in this router is 1. 1 normal 0 stub 0 nssa
 External flood list length 0
   BFD is enabled
    Area BACKBONE(0)
        Number of interfaces in this area is 2
        Area has no authentication
        SPF algorithm last executed 00:00:03.708 ago
        SPF algorithm executed 27 times
        Area ranges are
        Number of LSA 3. Checksum Sum 0x00AEF1
        Number of opaque link LSA 0. Checksum Sum 0x000000
        Number of DCbitless LSA 0
        Number of indication LSA 0
        Number of DoNotAge LSA 0
        Flood list length 0

The table below describes the significant fields shown in the display.

Table 10. show ip ospf Field Descriptions
Field	Description
Routing process “ospf 201” with ID 10.0.0.1	Process ID and OSPF router ID.
Supports...	Number of types of service supported (Type 0 only).
SPF schedule delay	Delay time (in seconds) of SPF calculations.
Minimum LSA interval	Minimum interval (in seconds) between link-state advertisements.
LSA group pacing timer	Configured LSA group pacing timer (in seconds).
Interface flood pacing timer	Configured LSA flood pacing timer (in milliseconds).
Retransmission pacing timer	Configured LSA retransmission pacing timer (in milliseconds).
Number of external LSA	Number of external link-state advertisements.
Number of opaque AS LSA	Number of opaque link-state advertisements.
Number of DCbitless external and opaque AS LSA	Number of demand circuit external and opaque link-state advertisements.
Number of DoNotAge external and opaque AS LSA	Number of do not age external and opaque link-state advertisements.
Number of areas in this router is	Number of areas configured for the router.
External flood list length	External flood list length.
BFD is enabled	BFD has been enabled on the OSPF process.

The following is an excerpt of output from the showipospf command when the OSPF Forwarding Address Suppression in Type-5 LSAs feature is configured:


Device#show ip ospf
.
.
.
Area 2
   Number of interfaces in this area is 4
   It is a NSSA area
   Perform type-7/type-5 LSA translation, suppress forwarding address
.
.
.
Routing Process "ospf 1" with ID 192.168.0.1
 Supports only single TOS(TOS0) routes
 Supports opaque LSA
 Supports Link-local Signaling (LLS)
 Initial SPF schedule delay 5000 msecs
 Minimum hold time between two consecutive SPFs 10000 msecs
 Maximum wait time between two consecutive SPFs 10000 msecs
 Incremental-SPF disabled
 Minimum LSA interval 5 secs
 Minimum LSA arrival 1000 msecs
 LSA group pacing timer 240 secs
 Interface flood pacing timer 33 msecs
 Retransmission pacing timer 66 msecs
 Number of external LSA 0. Checksum Sum 0x0     
 Number of opaque AS LSA 0. Checksum Sum 0x0     
 Number of DCbitless external and opaque AS LSA 0
 Number of DoNotAge external and opaque AS LSA 0
 Number of areas in this router is 0. 0 normal 0 stub 0 nssa
 External flood list length 0

The table below describes the significant fields shown in the display.

Table 11. show ip ospf Field Descriptions
Field	Description
Area	OSPF area and tag.
Number of interfaces...	Number of interfaces configured in the area.
It is...	Possible types are internal, area border, or autonomous system boundary.
Routing process “ospf 1” with ID 192.168.0.1	Process ID and OSPF router ID.
Supports...	Number of types of service supported (Type 0 only).
Initial SPF schedule delay	Delay time of SPF calculations at startup.
Minimum hold time	Minimum hold time (in milliseconds) between consecutive SPF calculations.
Maximum wait time	Maximum wait time (in milliseconds) between consecutive SPF calculations.
Incremental-SPF	Status of incremental SPF calculations.
Minimum LSA...	Minimum time interval (in seconds) between link-state advertisements, and minimum arrival time (in milliseconds) of link-state advertisements,
LSA group pacing timer	Configured LSA group pacing timer (in seconds).
Interface flood pacing timer	Configured LSA flood pacing timer (in milliseconds).
Retransmission pacing timer	Configured LSA retransmission pacing timer (in milliseconds).
Number of...	Number and type of link-state advertisements that have been received.
Number of external LSA	Number of external link-state advertisements.
Number of opaque AS LSA	Number of opaque link-state advertisements.
Number of DCbitless external and opaque AS LSA	Number of demand circuit external and opaque link-state advertisements.
Number of DoNotAge external and opaque AS LSA	Number of do not age external and opaque link-state advertisements.
Number of areas in this router is	Number of areas configured for the router listed by type.
External flood list length	External flood list length.

The following is sample output from the showipospf command. In this example, the user had configured the redistributionmaximum-prefix command to set a limit of 2000 redistributed routes. SPF throttling was configured with the timersthrottlespf command.


Device#show ip ospf 1
 Routing Process "ospf 1" with ID 10.0.0.1
 Supports only single TOS(TOS0) routes
 Supports opaque LSA
 Supports Link-local Signaling (LLS)
 It is an autonomous system boundary router
 Redistributing External Routes from,
    static, includes subnets in redistribution
    Maximum limit of redistributed prefixes 2000
    Threshold for warning message 75%
Initial SPF schedule delay 5000 msecs
 Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs

The table below describes the significant fields shown in the display.

Table 12. show ip ospf Field Descriptions
Field	Description
Routing process “ospf 1” with ID 10.0.0.1	Process ID and OSPF router ID.
Supports ...	Number of Types of Service supported.
It is ...	Possible types are internal, area border, or autonomous system boundary router.
Redistributing External Routes from	Lists of redistributed routes, by protocol.
Maximum limit of redistributed prefixes	Value set in the redistributionmaximum-prefix command to set a limit on the number of redistributed routes.
Threshold for warning message	Percentage set in the redistributionmaximum-prefix command for the threshold number of redistributed routes needed to cause a warning message. The default is 75 percent of the maximum limit.
Initial SPF schedule delay	Delay (in milliseconds) before initial SPF schedule for SPF throttling. Configured with the timersthrottlespf command.
Minimum hold time between two consecutive SPFs	Minimum hold time (in milliseconds) between two consecutive SPF calculations for SPF throttling. Configured with the timersthrottlespf command.
Maximum wait time between two consecutive SPFs	Maximum wait time (in milliseconds) between two consecutive SPF calculations for SPF throttling. Configured with the timersthrottlespf command.
Number of areas	Number of areas in router, area addresses, and so on.

The following is sample output from the showipospf command. In this example, the user had configured LSA throttling, and those lines of output are displayed in bold.


Device#show ip ospf 1
Routing Process "ospf 4" with ID 10.10.24.4
 Supports only single TOS(TOS0) routes
 Supports opaque LSA
 Supports Link-local Signaling (LLS)
 Initial SPF schedule delay 5000 msecs
 Minimum hold time between two consecutive SPFs 10000 msecs
 Maximum wait time between two consecutive SPFs 10000 msecs
 Incremental-SPF disabled
 Initial LSA throttle delay 100 msecs
 Minimum hold time for LSA throttle 10000 msecs
 
Maximum wait time for LSA throttle 45000 msecs
Minimum LSA arrival 1000 msecs
 LSA group pacing timer 240 secs
 Interface flood pacing timer 33 msecs
 Retransmission pacing timer 66 msecs
 Number of external LSA 0. Checksum Sum 0x0     
 Number of opaque AS LSA 0. Checksum Sum 0x0     
 Number of DCbitless external and opaque AS LSA 0
 Number of DoNotAge external and opaque AS LSA 0
 Number of areas in this router is 1. 1 normal 0 stub 0 nssa
 External flood list length 0
    Area 24
        Number of interfaces in this area is 2
        Area has no authentication
        SPF algorithm last executed 04:28:18.396 ago
        SPF algorithm executed 8 times
        Area ranges are
        Number of LSA 4. Checksum Sum 0x23EB9 
        Number of opaque link LSA 0. Checksum Sum 0x0     
        Number of DCbitless LSA 0
        Number of indication LSA 0
        Number of DoNotAge LSA 0
        Flood list length 0

The following is sample showipospf command. In this example, the user had configured the redistributionmaximum-prefix command to set a limit of 2000 redistributed routes. SPF throttling was configured with the timersthrottlespf command.


Device#show ip ospf 1
 Routing Process "ospf 1" with ID 192.168.0.0
 Supports only single TOS(TOS0) routes
 Supports opaque LSA
 Supports Link-local Signaling (LLS)
 It is an autonomous system boundary router
 Redistributing External Routes from,
    static, includes subnets in redistribution
    Maximum limit of redistributed prefixes 2000
    Threshold for warning message 75%
Initial SPF schedule delay 5000 msecs
 Minimum hold time between two consecutive SPFs 10000 msecs
 Maximum wait time between two consecutive SPFs 10000 msecs

The table below describes the significant fields shown in the display.

Table 13. show ip ospf Field Descriptions
Field	Description
Routing process “ospf 1” with ID 192.168.0.0.	Process ID and OSPF router ID.
Supports ...	Number of TOS supported.
It is ...	Possible types are internal, area border, or autonomous system boundary routers.
Redistributing External Routes from	Lists of redistributed routes, by protocol.
Maximum limit of redistributed prefixes	Value set in the redistributionmaximum-prefix command to set a limit on the number of redistributed routes.
Threshold for warning message	Percentage set in the redistributionmaximum-prefix command for the threshold number of redistributed routes needed to cause a warning message. The default is 75 percent of the maximum limit.
Initial SPF schedule delay	Delay (in milliseconds) before the initial SPF schedule for SPF throttling. Configured with the timersthrottlespf command.
Minimum hold time between two consecutive SPFs	Minimum hold time (in milliseconds) between two consecutive SPF calculations for SPF throttling. Configured with the timersthrottlespf command.
Maximum wait time between two consecutive SPFs	Maximum wait time (in milliseconds) between two consecutive SPF calculations for SPF throttling. Configured with the timersthrottlespf command.
Number of areas	Number of areas in router, area addresses, and so on.

The following is sample output from the showipospf command. In this example, the user had configured LSA throttling, and those lines of output are displayed in bold.


Device#show ip ospf 1
Routing Process "ospf 4" with ID 10.10.24.4
 Supports only single TOS(TOS0) routes
 Supports opaque LSA
 Supports Link-local Signaling (LLS)
 Initial SPF schedule delay 5000 msecs
 Minimum hold time between two consecutive SPFs 10000 msecs
 Maximum wait time between two consecutive SPFs 10000 msecs
 Incremental-SPF disabled
 Initial LSA throttle delay 100 msecs
 Minimum hold time for LSA throttle 10000 msecs
 Maximum wait time for LSA throttle 45000 msecs
Minimum LSA arrival 1000 msecs
 LSA group pacing timer 240 secs
 Interface flood pacing timer 33 msecs
 Retransmission pacing timer 66 msecs
 Number of external LSA 0. Checksum Sum 0x0     
 Number of opaque AS LSA 0. Checksum Sum 0x0     
 Number of DCbitless external and opaque AS LSA 0
 Number of DoNotAge external and opaque AS LSA 0
 Number of areas in this router is 1. 1 normal 0 stub 0 nssa
 External flood list length 0
    Area 24
        Number of interfaces in this area is 2
        Area has no authentication
        SPF algorithm last executed 04:28:18.396 ago
        SPF algorithm executed 8 times
        Area ranges are
        Number of LSA 4. Checksum Sum 0x23EB9 
        Number of opaque link LSA 0. Checksum Sum 0x0     
        Number of DCbitless LSA 0
        Number of indication LSA 0
        Number of DoNotAge LSA 0
        Flood list length 0

show ip ospf border-routers

To display the internal Open Shortest Path First (OSPF) routing table entries to an Area Border Router (ABR) and Autonomous System Boundary Router (ASBR), use the showipospfborder-routers command in privileged EXEC mode.

show ip ospf border-routers

Syntax Description

This command has no arguments or keywords.

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Examples

The following is sample output from the showipospfborder-routers command:


Device#show ip ospf border-routers
OSPF Process 109 internal Routing Table
Codes:  i - Intra-area route, I - Inter-area route
i 192.168.97.53   [10] via 172.16.1.53,   Serial0, ABR,  Area 0.0.0.3, SPF 3
i 192.168.103.51  [10] via 192.168.96.51, Serial0, ABR,  Area 0.0.0.3, SPF 3
I 192.168.103.52  [22] via 192.168.96.51, Serial0, ASBR, Area 0.0.0.3, SPF 3
I 192.168.103.52  [22] via 172.16.1.53,   Serial0, ASBR, Area 0.0.0.3, SPF 3

The table below describes the significant fields shown in the display.

Table 14. show ip ospf border-routers Field Descriptions
Field	Description
192.168.97.53	Router ID of the destination.
[10]	Cost of using this route.
via 172.16.1.53	Next hop toward the destination.
Serial0	Interface type for the outgoing interface.
ABR	The router type of the destination; it is either an ABR or ASBR or both.
Area	The area ID of the area from which this route is learned.
SPF 3	The internal number of the shortest path first (SPF) calculation that installs this route.

show ip ospf database

To display lists of information related to the Open Shortest Path First (OSPF) database for a specific router, use the show ipospfdatabase command in EXEC mode.

show ip ospf [process-id area-id] database

show ip ospf [process-id area-id] database [adv-router [ip-address] ]

show ip ospf [process-id area-id] database [asbr-summary] [link-state-id]

show ip ospf [process-id area-id] database [asbr-summary] [link-state-id] [adv-router [ip-address] ]

show ip ospf [process-id area-id] database [asbr-summary] [link-state-id] [self-originate] [link-state-id]

show ip ospf [process-id area-id] database [database-summary]

show ip ospf [process-id] database [external] [link-state-id]

show ip ospf [process-id] database [external] [link-state-id] [adv-router [ip-address] ]

show ip ospf [process-id area-id] database [external] [link-state-id] [self-originate] [link-state-id]

show ip ospf [process-id area-id] database [network] [link-state-id]

show ip ospf [process-id area-id] database [network] [link-state-id] [adv-router [ip-address] ]

show ip ospf [process-id area-id] database [network] [link-state-id] [self-originate] [link-state-id]

show ip ospf [process-id area-id] database [nssa-external] [link-state-id]

show ip ospf [process-id area-id] database [nssa-external] [link-state-id] [adv-router [ip-address] ]

show ip ospf [process-id area-id] database [nssa-external] [link-state-id] [self-originate] [link-state-id]

show ip ospf [process-id area-id] database [router] [link-state-id]

show ip ospf [process-id area-id] database [router] [adv-router [ip-address] ]

show ip ospf [process-id area-id] database [router] [self-originate] [link-state-id]

show ip ospf [process-id area-id] database [self-originate] [link-state-id]

show ip ospf [process-id area-id] database [summary] [link-state-id]

show ip ospf [process-id area-id] database [summary] [link-state-id] [adv-router [ip-address] ]

show ip ospf [process-id area-id] database [summary] [link-state-id] [self-originate] [link-state-id]

Syntax Description


`process-id`	(Optional) Internal identification. It is locally assigned and can be any positive integer. The number used here is the number assigned administratively when enabling the OSPF routing process.
`area-id`	(Optional) Area number associated with the OSPF address range defined in the network router configuration command used to define the particular area.
adv-router [`ip-address`	(Optional) Displays all the LSAs of the specified router. If no IP address is included, the information is about the local router itself (in this case, the same as self-originate ).
`link-state-id`	(Optional) Portion of the Internet environment that is being described by the advertisement. The value entered depends on the advertisement’s LS type. It must be entered in the form of an IP address. When the link state advertisement is describing a network, the `link-state-id` can take one of two forms: The network’s IP address (as in type 3 summary link advertisements and in autonomous system external link advertisements). A derived address obtained from the link state ID. (Note that masking a network links advertisement’s link state ID with the network’s subnet mask yields the network’s IP address.) When the link state advertisement is describing a router, the link state ID is always the described router’s OSPF router ID. When an autonomous system external advertisement (LS Type = 5) is describing a default route, its link state ID is set to Default Destination (0.0.0.0).
asbr-summary	(Optional) Displays information only about the autonomous system boundary router summary LSAs.
database-summary	(Optional) Displays how many of each type of LSA for each area there are in the database, and the total.
external	(Optional) Displays information only about the external LSAs.
network	(Optional) Displays information only about the network LSAs.
nssa-external	(Optional) Displays information only about the NSSA external LSAs.
router	(Optional) Displays information only about the router LSAs.
self-originate	(Optional) Displays only self-originated LSAs (from the local router).
summary	(Optional) Displays information only about the summary LSAs.

Command Modes

EXEC

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

The various forms of this command deliver information about different OSPF link state advertisements.

Examples

The following is sample output from the showipospfdatabase command when no arguments or keywords are used:


Device#show ip ospf database
OSPF Router with id(192.168.239.66) (Process ID 300)
                 Displaying Router Link States(Area 0.0.0.0)
  Link ID       ADV Router    Age        Seq#    Checksum  Link count
172.16.21.6   172.16.21.6    1731    0x80002CFB    0x69BC       8
172.16.21.5   172.16.21.5    1112    0x800009D2    0xA2B8       5
172.16.1.2    172.16.1.2     1662    0x80000A98    0x4CB6       9
172.16.1.1    172.16.1.1     1115    0x800009B6    0x5F2C       1
172.16.1.5    172.16.1.5     1691    0x80002BC     0x2A1A       5
172.16.65.6   172.16.65.6    1395    0x80001947    0xEEE1       4
172.16.241.5  172.16.241.5   1161    0x8000007C    0x7C70       1
172.16.27.6   172.16.27.6    1723    0x80000548    0x8641       4
172.16.70.6   172.16.70.6    1485    0x80000B97    0xEB84       6
                Displaying Net Link States(Area 0.0.0.0)
  Link ID       ADV Router      Age        Seq#       Checksum
172.16.1.3  192.168.239.66     1245    0x800000EC      0x82E
                Displaying Summary Net Link States(Area 0.0.0.0)
  Link ID       ADV Router       Age        Seq#       Checksum
172.16.240.0   172.16.241.5    1152      0x80000077      0x7A05
172.16.241.0   172.16.241.5    1152      0x80000070      0xAEB7
172.16.244.0   172.16.241.5    1152      0x80000071      0x95CB

The table below describes the significant fields shown in the display.

Table 15. show ip ospf Database Field Descriptions
Field	Description
Link ID	Router ID number.
ADV Router	Advertising router’s ID.
Age	Link state age.
Seq#	Link state sequence number (detects old or duplicate link state advertisements).
Checksum	Fletcher checksum of the complete contents of the link state advertisement.
Link count	Number of interfaces detected for router.

The following is sample output from the showipospfdatabase command with the asbr-summary keyword:


Device#show ip ospf database asbr-summary
OSPF Router with id(192.168.239.66) (Process ID 300)
                Displaying Summary ASB Link States(Area 0.0.0.0)
	LS age: 1463
	Options: (No TOS-capability)
	LS Type: Summary Links(AS Boundary Router)
	Link State ID: 172.16.245.1 (AS Boundary Router address)
	Advertising Router: 172.16.241.5
	LS Seq Number: 80000072
	Checksum: 0x3548
	Length: 28
	Network Mask: 0.0.0.0 TOS: 0  Metric: 1

The table below describes the significant fields shown in the display.

Table 16. show ip ospf database asbr-summary Field Descriptions
Field	Description
OSPF Router with id	Router ID number.
Process ID	OSPF process ID.
LS age	Link state age.
Options	Type of service options (Type 0 only).
LS Type	Link state type.
Link State ID	Link state ID (autonomous system boundary router).
Advertising Router	Advertising router’s ID.
LS Seq Number	Link state sequence (detects old or duplicate link state advertisements).
Checksum	LS checksum (Fletcher checksum of the complete contents of the link state advertisement).
Length	Length in bytes of the link state advertisement.
Network Mask	Network mask implemented.
TOS	Type of service.
Metric	Link state metric.

The following is sample output from the showipospfdatabase command with the external keyword:


Device#show ip ospf database external
OSPF Router with id(192.168.239.66) (Autonomous system 300)
                   Displaying AS External Link States
LS age: 280
Options: (No TOS-capability)
LS Type: AS External Link
Link State ID: 10.105.0.0 (External Network Number)
Advertising Router: 172.16.70.6
LS Seq Number: 80000AFD
Checksum: 0xC3A
Length: 36
Network Mask: 255.255.0.0
     		Metric Type: 2 (Larger than any link state path)
     		TOS: 0
     		Metric: 1
     		Forward Address: 0.0.0.0
     		External Route Tag: 0

The table below describes the significant fields shown in the display.

Table 17. show ip ospf database external Field Descriptions
Field	Description
OSPF Router with id	Router ID number.
Autonomous system	OSPF autonomous system number (OSPF process ID).
LS age	Link state age.
Options	Type of service options (Type 0 only).
LS Type	Link state type.
Link State ID	Link state ID (external network number).
Advertising Router	Advertising router’s ID.
LS Seq Number	Link state sequence number (detects old or duplicate link state advertisements).
Checksum	LS checksum (Fletcher checksum of the complete contents of the LSA).
Length	Length in bytes of the link state advertisement.
Network Mask	Network mask implemented.
Metric Type	External Type.
TOS	Type of service.
Metric	Link state metric.
Forward Address	Forwarding address. Data traffic for the advertised destination will be forwarded to this address. If the forwarding address is set to 0.0.0.0, data traffic will be forwarded instead to the advertisement’s originator.
External Route Tag	External route tag, a 32-bit field attached to each external route. This is not used by the OSPF protocol itself.

The following is sample output from the showipospfdatabase command with the network keyword:


Device#show ip ospf database network
 OSPF Router with id(192.168.239.66) (Process ID 300)
                Displaying Net Link States(Area 0.0.0.0)
LS age: 1367
Options: (No TOS-capability)
LS Type: Network Links
Link State ID: 172.16.1.3 (address of Designated Router)
Advertising Router: 192.168.239.66
LS Seq Number: 800000E7
Checksum: 0x1229
Length: 52
Network Mask: 255.255.255.0
        Attached Router: 192.168.239.66
        Attached Router: 172.16.241.5
        Attached Router: 172.16.1.1
        Attached Router: 172.16.54.5
        Attached Router: 172.16.1.5

The table below describes the significant fields shown in the display.

Table 18. show ip ospf database network Field Descriptions
Field	Description
OSPF Router with id	Router ID number.
Process ID 300	OSPF process ID.
LS age	Link state age.
Options	Type of service options (Type 0 only).
LS Type:	Link state type.
Link State ID	Link state ID of designated router.
Advertising Router	Advertising router’s ID.
LS Seq Number	Link state sequence (detects old or duplicate link state advertisements).
Checksum	LS checksum (Fletcher checksum of the complete contents of the link state advertisement).
Length	Length in bytes of the link state advertisement.
Network Mask	Network mask implemented.
AS Boundary Router	Definition of router type.
Attached Router	List of routers attached to the network, by IP address.

The following is sample output from the showipospfdatabase command with the router keyword:


Device#show ip ospf database router
OSPF Router with id(192.168.239.66) (Process ID 300)
Displaying Router Link States(Area 0.0.0.0)
LS age: 1176
Options: (No TOS-capability)
LS Type: Router Links
Link State ID: 172.16.21.6
Advertising Router: 172.16.21.6
LS Seq Number: 80002CF6
Checksum: 0x73B7
Length: 120
AS Boundary Router
155   Number of Links: 8
Link connected to: another Router (point-to-point)
(link ID) Neighboring Router ID: 172.16.21.5
(Link Data) Router Interface address: 172.16.21.6
Number of TOS metrics: 0
TOS 0 Metrics: 2

The table below describes the significant fields shown in the display.

Table 19. show ip ospf database router Field Descriptions
Field	Description
OSPF Router with id	Router ID number.
Process ID	OSPF process ID.
LS age	Link state age.
Options	Type of service options (Type 0 only).
LS Type	Link state type.
Link State ID	Link state ID.
Advertising Router	Advertising router’s ID.
LS Seq Number	Link state sequence (detects old or duplicate link state advertisements).
Checksum	LS checksum (Fletcher checksum of the complete contents of the link state advertisement).
Length	Length in bytes of the link state advertisement.
AS Boundary Router	Definition of router type.
Number of Links	Number of active links.
link ID	Link type.
Link Data	Router interface address.
TOS	Type of service metric (Type 0 only).

The following is sample output from showipospfdatabase command with the summary keyword:


Device#show ip ospf database summary
       OSPF Router with id(192.168.239.66) (Process ID 300)
                Displaying Summary Net Link States(Area 0.0.0.0)
LS age: 1401
Options: (No TOS-capability)
LS Type: Summary Links(Network)
Link State ID: 172.16.240.0 (summary Network Number)
Advertising Router: 172.16.241.5
LS Seq Number: 80000072
Checksum: 0x84FF
Length: 28
Network Mask: 255.255.255.0   TOS: 0  Metric: 1

The table below describes the significant fields shown in the display.

Table 20. show ip ospf database summary Field Descriptions
Field	Description
OSPF Router with id	Router ID number.
Process ID	OSPF process ID.
LS age	Link state age.
Options	Type of service options (Type 0 only).
LS Type	Link state type.
Link State ID	Link state ID (summary network number).
Advertising Router	Advertising router’s ID.
LS Seq Number	Link state sequence (detects old or duplicate link state advertisements).
Checksum	LS checksum (Fletcher checksum of the complete contents of the link state advertisement).
Length	Length in bytes of the link state advertisement.
Network Mask	Network mask implemented.
TOS	Type of service.
Metric	Link state metric.

The following is sample output from showipospfdatabase command with the database-summary keyword:


Device#show ip ospf database database-summary
OSPF Router with ID (10.0.0.1) (Process ID 1)
Area 0 database summary
  LSA Type      Count    Delete   Maxage
  Router        3        0        0
  Network       0        0        0
  Summary Net   0        0        0
  Summary ASBR  0        0        0
  Type-7 Ext    0        0        0
    Self-originated Type-7  0
Opaque Link     0        0        0
  Opaque Area   0        0        0
  Subtotal      3        0        0
Process 1 database summary
  LSA Type      Count    Delete   Maxage
  Router        3        0        0
  Network       0        0        0
  Summary Net   0        0        0
  Summary ASBR  0        0        0
  Type-7 Ext    0        0        0
  Opaque Link   0        0        0
  Opaque Area   0        0        0
  Type-5 Ext    0        0        0
      Self-originated Type-5  200
Opaque AS       0        0        0
  Total       203        0        0

The table below describes the significant fields shown in the display.

Table 21. show ip ospf database database-summary Field Descriptions
Field	Description
Area 0 database summary	Area number.
Count	Count of LSAs of the type identified in the first column.
Router	Number of router link state advertisements in that area.
Network	Number of network link state advertisements in that area.
Summary Net	Number of summary link state advertisements in that area.
Summary ASBR	Number of summary autonomous system boundary router (ASBR) link state advertisements in that area.
Type-7 Ext	Type-7 LSA count.
Self-originated Type-7	Self-originated Type-7 LSA.
Opaque Link	Type-9 LSA count.
Opaque Area	Type-10 LSA count
Subtotal	Sum of LSAs for that area.
Delete	Number of link state advertisements that are marked “Deleted” in that area.
Maxage	Number of link state advertisements that are marked “Maxaged” in that area.
Process 1 database summary	Database summary for the process.
Count	Count of LSAs of the type identified in the first column.
Router	Number of router link state advertisements in that process.
Network	Number of network link state advertisements in that process.
Summary Net	Number of summary link state advertisements in that process.
Summary ASBR	Number of summary autonomous system boundary router (ASBR) link state advertisements in that process.
Type-7 Ext	Type-7 LSA count.
Opaque Link	Type-9 LSA count.
Opaque Area	Type-10 LSA count.
Type-5 Ext	Type-5 LSA count.
Self-Originated Type-5	Self-originated Type-5 LSA count.
Opaque AS	Type-11 LSA count.
Total	Sum of LSAs for that process.
Delete	Number of link state advertisements that are marked “Deleted” in that process.
Maxage	Number of link state advertisements that are marked “Maxaged” in that process.

show ip ospf interface

To display interface information related to Open Shortest Path First (OSPF), use the show ip ospf interface command in user EXEC or privileged EXEC mode.

show ip [ospf] [process-id] interface [type number] [brief] [multicast] [topology {topology-name | base}]

Syntax Description


`process-id`	(Optional) Process ID number. If this argument is included, only information for the specified routing process is included. The range is 1 to 65535.
`type`	(Optional) Interface type. If the `type` argument is included, only information for the specified interface type is included.
`number`	(Optional) Interface number. If the `number` argument is included, only information for the specified interface number is included.
brief	(Optional) Displays brief overview information for OSPF interfaces, states, addresses and masks, and areas on the device.
multicast	(Optional) Displays multicast information.
topology `topology-name`	(Optional) Displays OSPF-related information about the named topology instance.
topology base	(Optional) Displays OSPF-related information about the base topology.

Command Modes

User EXEC (>)

Privileged EXEC (#)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Examples

The following is sample output from the show ip ospf interface command when Ethernet interface 0/0 is specified:


Device#show ip ospf interface ethernet 0/0

Ethernet0/0 is up, line protocol is up
  Internet Address 192.168.254.202/24, Area 0
  Process ID 1, Router ID 192.168.99.1, Network Type BROADCAST, Cost: 10
  Topology-MTID    Cost    Disabled    Shutdown      Topology Name
        0           10        no          no            Base
  Transmit Delay is 1 sec, State DR, Priority 1
  Designated Router (ID) 192.168.99.1, Interface address 192.168.254.202
  Backup Designated router (ID) 192.168.254.10, Interface address 192.168.254.10
  Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
    oob-resync timeout 40
    Hello due in 00:00:05
  Supports Link-local Signaling (LLS)
  Cisco NSF helper support enabled
  IETF NSF helper support enabled
  Index 1/1, flood queue length 0
  Next 0x0(0)/0x0(0)
  Last flood scan length is 1, maximum is 1
  Last flood scan time is 0 msec, maximum is 0 msec
  Neighbor Count is 1, Adjacent neighbor count is 1 
    Adjacent with neighbor 192.168.254.10  (Backup Designated Router)
  Suppress hello for 0 neighbor(s)

In Cisco IOS Release 12.2(33)SRB, the following sample output from the show ip ospf interface brief topology VOICE command shows a summary of information, including a confirmation that the Multitopology Routing (MTR) VOICE topology is configured in the interface configuration:


Device#show ip ospf interface brief topology VOICE

VOICE Topology (MTID 10)
Interface    PID   Area            IP Address/Mask    Cost  State Nbrs F/C
Lo0          1     0               10.0.0.2/32        1     LOOP  0/0
Se2/0        1     0               10.1.0.2/30        10    P2P   1/1

The following sample output from the show ip ospf interface brief topology VOICE command displays details of the MTR VOICE topology for the interface. When the command is entered without the brief keyword, more information is displayed.


Device#show ip ospf interface topology VOICE

                 VOICE Topology (MTID 10)
Loopback0 is up, line protocol is up
   Internet Address 10.0.0.2/32, Area 0
   Process ID 1, Router ID 10.0.0.2, Network Type LOOPBACK
   Topology-MTID    Cost    Disabled    Shutdown      Topology Name
         10          1         no          no            VOICE
   Loopback interface is treated as a stub Host Serial2/0 is up, line protocol is up
   Internet Address 10.1.0.2/30, Area 0
   Process ID 1, Router ID 10.0.0.2, Network Type POINT_TO_POINT
   Topology-MTID    Cost    Disabled    Shutdown      Topology Name
         10          10        no          no            VOICE
   Transmit Delay is 1 sec, State POINT_TO_POINT
   Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
     oob-resync timeout 40
     Hello due in 00:00:03
   Supports Link-local Signaling (LLS)
   Cisco NSF helper support enabled
   IETF NSF helper support enabled
   Index 1/1, flood queue length 0
   Next 0x0(0)/0x0(0)
   Last flood scan length is 1, maximum is 1
   Last flood scan time is 0 msec, maximum is 0 msec
   Neighbor Count is 1, Adjacent neighbor count is 1
     Adjacent with neighbor 10.0.0.1
   Suppress hello for 0 neighbor(s)

In Cisco IOS Release 12.2(33)SRC, the following sample output from the show ip ospf interface command displays details about the configured Time-to-Live (TTL) limits:

Device#show ip ospf interface ethernet 0
.
.
.
Strict TTL checking enabled
! or a message similar to the following is displayed
Strict TTL checking enabled, up to 4 hops allowed
.
.
.

The table below describes the significant fields shown in the displays.

Table 22. show ip ospf interface Field Descriptions
Field	Description
Ethernet	Status of the physical link and operational status of the protocol.
Process ID	OSPF process ID.
Area	OSPF area.
Cost	Administrative cost assigned to the interface.
State	Operational state of the interface.
Nbrs F/C	OSPF neighbor count.
Internet Address	Interface IP address, subnet mask, and area address.
Topology-MTID	MTR topology Multitopology Identifier (MTID). A number assigned so that the protocol can identify the topology associated with information that it sends to its peers.
Transmit Delay	Transmit delay in seconds, interface state, and device priority.
Designated Router	Designated router ID and respective interface IP address.
Backup Designated router	Backup designated router ID and respective interface IP address.
Timer intervals configured	Configuration of timer intervals.
Hello	Number of seconds until the next hello packet is sent out this interface.
Strict TTL checking enabled	Only one hop is allowed.
Strict TTL checking enabled, up to 4 hops allowed	A set number of hops has been explicitly configured.
Neighbor Count	Count of network neighbors and list of adjacent neighbors.

show ip ospf neighbor

To display Open Shortest Path First (OSPF) neighbor information on a per-interface basis, use the showipospfneighbor command in privileged EXEC mode.

show ip ospf neighbor [interface-type interface-number] [neighbor-id] [detail] [ summary [ per-instance] ]

Syntax Description


`interface-type` `interface-number`	(Optional) Type and number associated with a specific OSPF interface.
`neighbor-id`	(Optional) Neighbor hostname or IP address in A.B.C.D format.
detail	(Optional) Displays all neighbors given in detail (lists all neighbors).
summary	(Optional) Displays total number summary of all neighbors.
per-instance	(Optional) Displays total number of neighbors in each neighbor state. The output is printed for each configured OSPF instance separately.

Command Modes

Privileged EXEC (#)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Examples

The following sample output from the show ip ospf neighbor command shows a single line of summary information for each neighbor:


Device#show ip ospf neighbor

Neighbor ID 		Pri   State        Dead Time     Address         Interface
10.199.199.137  1    FULL/DR       0:00:31    192.168.80.37      Ethernet0
172.16.48.1     1    FULL/DROTHER  0:00:33    172.16.48.1        Fddi0
172.16.48.200   1    FULL/DROTHER  0:00:33    172.16.48.200      Fddi0
10.199.199.137  5    FULL/DR       0:00:33    172.16.48.189      Fddi0

The following is sample output showing summary information about the neighbor that matches the neighbor ID:


Device#show ip ospf neighbor 10.199.199.137
 
Neighbor 10.199.199.137, interface address 192.168.80.37
    In the area 0.0.0.0 via interface Ethernet0
    Neighbor priority is 1, State is FULL
    Options 2
    Dead timer due in 0:00:32
    Link State retransmission due in 0:00:04
 Neighbor 10.199.199.137, interface address 172.16.48.189
    In the area 0.0.0.0 via interface Fddi0
    Neighbor priority is 5, State is FULL
    Options 2
    Dead timer due in 0:00:32
    Link State retransmission due in 0:00:03

If you specify the interface along with the neighbor ID, the system displays the neighbors that match the neighbor ID on the interface, as in the following sample display:


Device#show ip ospf neighbor ethernet 0 10.199.199.137
 
Neighbor 10.199.199.137, interface address 192.168.80.37
    In the area 0.0.0.0 via interface Ethernet0
    Neighbor priority is 1, State is FULL
    Options 2
    Dead timer due in 0:00:37
    Link State retransmission due in 0:00:04

You can also specify the interface without the neighbor ID to show all neighbors on the specified interface, as in the following sample display:


Device#show ip ospf neighbor fddi 0

   ID          Pri   State        Dead Time     Address         Interface
172.16.48.1     1    FULL/DROTHER  0:00:33    172.16.48.1       Fddi0
172.16.48.200   1    FULL/DROTHER  0:00:32    172.16.48.200     Fddi0
10.199.199.137  5    FULL/DR       0:00:32    172.16.48.189     Fddi0

The following is sample output from the show ip ospf neighbor detail command:


Device#show ip ospf neighbor detail
 
Neighbor 192.168.5.2, interface address 10.225.200.28
    In the area 0 via interface GigabitEthernet1/0/0
    Neighbor priority is 1, State is FULL, 6 state changes
    DR is 10.225.200.28 BDR is 10.225.200.30
    Options is 0x42
    LLS Options is 0x1 (LR), last OOB-Resync 00:03:08 ago
    Dead timer due in 00:00:36
    Neighbor is up for 00:09:46
   Index 1/1, retransmission queue length 0, number of retransmission 1
    First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0)
    Last retransmission scan length is 1, maximum is 1
    Last retransmission scan time is 0 msec, maximum is 0 msec

The table below describes the significant fields shown in the displays.

Table 23. show ip ospf neighbor detail Field Descriptions
Field	Description
Neighbor	Neighbor router ID.
interface address	IP address of the interface.
In the area	Area and interface through which the OSPF neighbor is known.
Neighbor priority	Router priority of the neighbor and neighbor state.
State	OSPF state. If one OSPF neighbor has enabled TTL security, the other side of the connection will show the neighbor in the INIT state.
state changes	Number of state changes since the neighbor was created. This value can be reset using the clearipospfcountersneighbor command.
DR is	Router ID of the designated router for the interface.
BDR is	Router ID of the backup designated router for the interface.
Options	Hello packet options field contents. (E-bit only. Possible values are 0 and 2; 2 indicates area is not a stub; 0 indicates area is a stub.)
LLS Options..., last OOB-Resync	Link-Local Signaling and out-of-band (OOB) link-state database resynchronization performed hours:minutes:seconds ago. This is nonstop forwarding (NSF) information. The field indicates the last successful out-of-band resynchronization with the NSF-capable router.
Dead timer due in	Expected time in hours:minutes:seconds before Cisco IOS software will declare the neighbor dead.
Neighbor is up for	Number of hours:minutes:seconds since the neighbor went into the two-way state.
Index	Neighbor location in the area-wide and autonomous system-wide retransmission queue.
retransmission queue length	Number of elements in the retransmission queue.
number of retransmission	Number of times update packets have been re-sent during flooding.
First	Memory location of the flooding details.
Next	Memory location of the flooding details.
Last retransmission scan length	Number of link state advertisements (LSAs) in the last retransmission packet.
maximum	Maximum number of LSAs sent in any retransmission packet.
Last retransmission scan time	Time taken to build the last retransmission packet.
maximum	Maximum time, in milliseconds, taken to build any retransmission packet.

Examples

The following is sample output from the show ip ospf neighbor command showing a single line of summary information for each neighbor. If one OSPF neighbor has enabled TTL security, the other side of the connection will show the neighbor in the INIT state.


Device#show ip ospf neighbor

Neighbor ID 			Pri   State        Dead Time     Address         Interface
10.199.199.137  1    FULL/DR       0:00:31    192.168.80.37      Ethernet0
172.16.48.1     1    FULL/DROTHER  0:00:33    172.16.48.1        Fddi0
172.16.48.200   1    FULL/DROTHER  0:00:33    172.16.48.200      Fddi0
10.199.199.137  5    FULL/DR       0:00:33    172.16.48.189      Fddi0
172.16.1.201		1	INIT/DROTHER			00.00.35		10.1.1.201			Ethernet0/0

The following sample output from the show ip ospf neighbor command shows the network from the neighbor’s point of view:


Device#show ip ospf neighbor 192.0.2.1
            OSPF Router with ID (192.1.1.1) (Process ID 1)

                     Area with ID (0)

Neighbor with Router ID 192.0.2.1:
  Reachable over:
    Ethernet0/0, IP address 192.0.2.1, cost 10

  SPF was executed 1 times, distance to computing router 10

  Router distance table:
           192.1.1.1   i  [10]
           192.0.2.1   i  [0]
           192.3.3.3   i  [10]
           192.4.4.4   i  [20]
           192.5.5.5   i  [20]

  Network LSA distance table:
      192.2.12.2   i  [10]
      192.2.13.3   i  [20]
      192.2.14.4   i  [20]
      192.2.15.5   i  [20]

The following is sample output from the show ip ospf neighbor summary command:


Device#show ip ospf neighbor summary

    Neighbor summary for all OSPF processes

DOWN         0
ATTEMPT      0
INIT         0
2WAY         0
EXSTART      0
EXCHANGE     0
LOADING      0
FULL         1
Total count  1    (Undergoing NSF 0)

The following is sample output from the show ip ospf neighbor summary per-instance command:


Device#show ip ospf neighbor summary

      OSPF Router with ID (1.0.0.10) (Process ID 1)

DOWN         0
ATTEMPT      0
INIT         0
2WAY         0
EXSTART      0
EXCHANGE     0
LOADING      0
FULL         1
Total count  1    (Undergoing NSF 0)


             Neighbor summary for all OSPF processes

DOWN         0
ATTEMPT      0
INIT         0
2WAY         0
EXSTART      0
EXCHANGE     0
LOADING      0
FULL         1
Total count  1    (Undergoing NSF 0)

Table 24. show ip ospf neighbor summary and show ip ospf neighbor summary per-instance Field Descriptions
Field	Description
DOWN	No information (hellos) has been received from this neighbor, but hello packets can still be sent to the neighbor in this state.
ATTEMPT	This state is only valid for manually configured neighbors in a Non-Broadcast Multi-Access (NBMA) environment. In Attempt state, the router sends unicast hello packets every poll interval to the neighbor, from which hellos have not been received within the dead interval.
INIT	This state specifies that the router has received a hello packet from its neighbor, but the receiving router's ID was not included in the hello packet. When a router receives a hello packet from a neighbor, it should list the sender's router ID in its hello packet as an acknowledgment that it received a valid hello packet.
2WAY	This state designates that bi-directional communication has been established between two routers.
EXSTART	This state is the first step in creating an adjacency between the two neighboring routers. The goal of this step is to decide which router is active, and to decide upon the initial DD sequence number. Neighbor conversations in this state or greater are called adjacencies.
EXCHANGE	In this state, OSPF routers exchange database descriptor (DBD) packets. Database descriptors contain link-state advertisement (LSA) headers only and describe the contents of the entire link-state database. Each DBD packet has a sequence number which can be incremented only by the active router which is explicitly acknowledged by the secondary router. Routers also send link-state request packets and link-state update packets (which contain the entire LSA) in this state. The contents of the DBD received are compared to the information contained in the routers link-state database to check if new or more current link-state information is available with the neighbor.
LOADING	In this state, the actual exchange of link state information occurs. Based on the information provided by the DBDs, routers send link-state request packets. The neighbor then provides the requested link-state information in link-state update packets. During the adjacency, if a device receives an outdated or missing LSA, it requests that LSA by sending a link-state request packet. All link-state update packets are acknowledged.
FULL	In this state, devices are fully adjacent with each other. All the device and network LSAs are exchanged and the devices' databases are fully synchronized. Full is the normal state for an OSPF device. If a device is stuck in another state, it's an indication that there are problems in forming adjacencies. The only exception to this is the 2-way state, which is normal in a broadcast network. Devices achieve the full state with their DR and BDR only. Neighbors always see each other as 2-way.

show ip ospf virtual-links

To display parameters and the current state of Open Shortest Path First (OSPF) virtual links, use the showipospfvirtual-links command in EXEC mode.

show ip ospf virtual-links

Syntax Description

This command has no arguments or keywords.

Command Modes

EXEC

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

The information displayed by the showipospfvirtual-links command is useful in debugging OSPF routing operations.

Examples

The following is sample output from the showipospfvirtual-links command:


Device#show ip ospf virtual-links
Virtual Link to router 192.168.101.2 is up
Transit area 0.0.0.1, via interface Ethernet0, Cost of using 10
Transmit Delay is 1 sec, State POINT_TO_POINT
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 0:00:08
Adjacency State FULL

The table below describes the significant fields shown in the display.

Table 25. show ip ospf virtual-links Field Descriptions
Field	Description
Virtual Link to router 192.168.101.2 is up	Specifies the OSPF neighbor, and if the link to that neighbor is up or down.
Transit area 0.0.0.1	The transit area through which the virtual link is formed.
via interface Ethernet0	The interface through which the virtual link is formed.
Cost of using 10	The cost of reaching the OSPF neighbor through the virtual link.
Transmit Delay is 1 sec	The transmit delay (in seconds) on the virtual link.
State POINT_TO_POINT	The state of the OSPF neighbor.
Timer intervals...	The various timer intervals configured for the link.
Hello due in 0:00:08	When the next hello is expected from the neighbor.
Adjacency State FULL	The adjacency state between the neighbors.

summary-address (OSPF)

To create aggregate addresses for Open Shortest Path First (OSPF), use the summary-address command in router configuration mode. To restore the default, use the no form of this command.

summary-address commandsummary-address {ip-address mask | prefix mask} [not-advertise] [tag tag] [nssa-only]

no summary-address {ip-address mask | prefix mask} [not-advertise] [tag tag] [nssa-only]

Syntax Description


`ip-address`	Summary address designated for a range of addresses.
`mask`	IP subnet mask used for the summary route.
`prefix`	IP route prefix for the destination.
not-advertise	(Optional) Suppresses routes that match the specified prefix/mask pair. This keyword applies to OSPF only.
tag `tag`	(Optional) Specifies the tag value that can be used as a “match” value for controlling redistribution via route maps. This keyword applies to OSPF only.
nssa-only	(Optional) Sets the nssa-only attribute for the summary route (if any) generated for the specified prefix, which limits the summary to not-so-stubby-area (NSSA) areas.

Command Default

This command behavior is disabled by default.

Command Modes

Router configuration

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

R outes learned from other routing protocols can be summarized. The metric used to advertise the summary is the lowest metric of all the more specific routes. This command helps reduce the size of the routing table.

Using this command for OSPF causes an OSPF Autonomous System Boundary Router (ASBR) to advertise one external route as an aggregate for all redistributed routes that are covered by the address. For OSPF, this command summarizes only routes from other routing protocols that are being redistributed into OSPF. Use the area range command for route summarization between OSPF areas.

OSPF does not support the summary-address 0.0.0.0 0.0.0.0 command.

Examples

In the following example, the summary address 10.1.0.0 includes address 10.1.1.0, 10.1.2.0, 10.1.3.0, and so on. Only the address 10.1.0.0 is advertised in an external link-state advertisement.


Device(config)#summary-address 10.1.0.0 255.255.0.0

Related Commands


Command	Description
area range	Consolidates and summarizes routes at an area boundary.
ip ospf authentication-key	Assigns a password to be used by neighboring routers that are using the simple password authentication of OSPF.
ip ospf message-digest-key	Enables OSPF MD5 authentication.

timers throttle spf

To turn on Open Shortest Path First ( OSPF) shortest path first (SPF) throttling, use the timers throttle spf command in the appropriate configuration mode. To turn off OSPF SPF throttling, use the no form of this command.

timers throttle spf spf-start spf-hold spf-max-wait

no timers throttle spf spf-start spf-hold spf-max-wait

Syntax Description


`spf-start`	Initial delay to schedule an SPF calculation after a change, in milliseconds. Range is from 1 to 600000. In OSPF for IPv6, the default value is 5000.
`spf-hold`	Minimum hold time between two consecutive SPF calculations, in milliseconds. Range is from 1 to 600000. In OSPF for IPv6, the default value is 10,000.
`spf-max-wait`	Maximum wait time between two consecutive SPF calculations, in milliseconds. Range is from 1 to 600000. In OSPF for IPv6, the default value is 10,000.

Command Default

SPF throttling is not set.

Command Modes

Address family configuration (config-router-af) Router address family topology configuration (config-router-af-topology) Router configuration (config-router) OSPF for IPv6 router configuration (config-rtr)

Command History


Release	Modification
Cisco IOS XE Fuji 16.9.2	This command was introduced.

Usage Guidelines

The first wait interval between SPF calculations is the amount of time in milliseconds specified by the spf-start argument. Each consecutive wait interval is two times the current hold level in milliseconds until the wait time reaches the maximum time in milliseconds as specified by the spf-max-wait argument. Subsequent wait times remain at the maximum until the values are reset or a link-state advertisement (LSA) is received between SPF calculations.

Release 12.2(33)SRB

If you plan to configure the Multi-Topology Routing (MTR) feature, you need to enter the timers throttle spf command in router address family topology configuration mode in order to make this OSPF router configuration command become topology-aware.

Release 15.2(1)T

When you configure the ospfv3 network manet command on any interface attached to the OSPFv3 process, the default values for the spf-start , spf-hold , and the spf-max-wait arguments are reduced to 1000 milliseconds, 1000 milliseconds, and 2000 milliseconds respectively.

Examples

The following example shows how to configure a router with the delay, hold, and maximum interval values for the timers throttle spf command set at 5, 1000, and 90,000 milliseconds, respectively.


router ospf 1
 router-id 10.10.10.2
 log-adjacency-changes
 timers throttle spf 5 1000 90000 
 redistribute static subnets
 network 10.21.21.0 0.0.0.255 area 0
 network 10.22.22.0 0.0.0.255 area 00

The following example shows how to configure a router using IPv6 with the delay, hold, and maximum interval values for the timers throttle spf command set at 500, 1000, and 10,000 milliseconds, respectively.


ipv6 router ospf 1 
 event-log size 10000 one-shot
 log-adjacency-changes  
 timers throttle spf 500 1000 10000

Related Commands


Command	Description
ospfv3 network manet	Sets the network type to Mobile Ad Hoc Network (MANET).

Bias-Free Language

Results

Chapter: IP Routing Commands

IP Routing Commands

accept-lifetime

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

area nssa

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

area virtual-link

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Release 12.2(33)SRB

Examples

Related Commands

default-information originate (OSPF)

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

distance (OSPF)

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Task ID

Examples

Related Commands

eigrp log-neighbor-changes

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

ip authentication key-chain eigrp

Syntax Description

Command Default

Command Modes

Command History

Examples

Related Commands

ip authentication mode eigrp

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

ip bandwidth-percent eigrp

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

ip cef load-sharing algorithm

Syntax Description