Static Routing

address-family (static)

To enter various address family configuration modes while configuring static routes, use the address-family command in the appropriate configuration mode. To disable support for an address family, use the no form of this command.

address-family { ipv4 | ipv6 } { unicast }

no address-family { ipv4 | ipv6 } { unicast }

Syntax Description

ipv4

Specifies IP Version 4 address prefixes.

ipv6

Specifies IP Version 6 address prefixes. This option is available only in static router configuration mode.

unicast

Specifies unicast address prefixes.

Command Modes

Router static configuration

Usage Guidelines

Use the address-family command to enter various address family configuration modes while configuring static routing sessions. From address family configuration mode, you can configure static routes using the route command.

Examples

The following example shows how to enter IPv6 unicast address family mode: 


  Router(config)# router static
  Router(config-static)# address-family ipv6 unicast 
  Router(config-static-afi)#

Related Commands

Command

Description

Route Static

Establishes a static route.

maximum path (static)

To change the maximum number of allowable static routes, use the maximum path command in static router configuration mode. To remove the maximum path command from the configuration file and restore the system to its default condition, use the no form of this command.

maximum path { ipv4 | ipv6 } value

no maximum path { ipv4 | ipv6 } value

Syntax Description

ipv4 | ipv6

Specifies IP Version 4 (IPv4) or IP Version 6 (IPv6) address prefixes.

value

Maximum number of static routes for the given AFI. The range is 1 to 140000.

Command Default

value : 4000

Command Modes

Static router configuration

Usage Guidelines

If you use the maximum path command to reduce the configured maximum allowed number of static routes for a given table below the number of static routes currently configured, the change is rejected. In addition, if you commit a batch of routes that would, when grouped, push the number of static routes configured above the maximum allowed, the first n routes in the batch and the number previously configured are accepted, and the remainder rejected. The n argument is the difference between the maximum number allowed and the number previously configured.

Examples

The following example shows how to set the maximum number of static IPv4 routes to 100000: 


  Router(config-static)# maximum path ipv4 100000

The following example shows how to remove the preceding configuration and set the maximum number of static IPv4 routes back to the default: 

Router(config-static)# no maximum path ipv4 100000

Related Commands

Command

Description

route static

Enters static router configuration mode.

show route static

Displays the static routes in a routing table.

route (static)

To establish static routes, use the route command in address family configuration mode. To remove the route command from the configuration, use the no form of this command.

prefix / mask { ip-address | type interface-path-id [ ip-address | type interface-path-id ] [ behavior | utef ] [ track track-object-name ] [ tunnel-id ] [ vrflabel vrf-label ] [distance] [ description text ] [ tag tag ] [permanent] }

Syntax Description

prefix / mask

IP route prefix and prefix mask for the destination.

The network mask can be specified in either of two ways:

  • The network mask can be a four-part, dotted-decimal address. For example, 255.0.0.0 indicates that each bit equal to 1 means the corresponding address bit is a network address.

  • The network mask can be indicated as a slash (/) and number. For example, /8 indicates that the first 8 bits of the mask are 1s, and the corresponding bits of the address are the network address.

ip-address

IP address of the next hop that can be used to reach that network.

  • For IPv4 address–the IP address is required, not optional, if the interface type and interface-path-id arguments are not specified. You can specify an IP address and an interface type and interface path.

  • For IPv6 link-local address–the interface type and interface-path-id arguments are required. The route is not valid, if the interface type and interface-path-id arguments are not specified.

Note

 

A forwarding router's IP address or an interface or virtual interface path ID can be configured, in any order.

behavior

Define the behavior by selecting the appropriate option.
utef

Static programs the utef SID with the context of controller address.

type

Interface type. For more information, use the question mark (?) online help function.

interface-path-id

Physical interface or virtual interface.

Note

 

Use the show interfaces command to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark ( ? ) online help function.

Note

 

A forwarding router's IP address or an interface or virtual interface path ID can be configured, in any order.

distance

(Optional) Administrative distance. Range is 1 to 254.

description text

(Optional) Specifies a description of the static route.

tag tag

(Optional) Specifies a tag value that can be used as a match for controlling redistribution using route policies. Range is 1 to 4294967295.

permanent

(Optional) Specifies that the route is not removed from the routing table, even if the next-hop interface shuts down or next-hop IP address is not reachable.

track track-object-name

Installs static routes in RIB only if track is UP.

tunnel-id tunnel-id

Specifies a Tunnel ID.

vrflabel vrf-label

Specifies a VRF label.

Command Default

No static route is established.

Command Modes

Address family configuration

Table 1. Command History:

Release

Modification

Release 24.1.1

The utef keyword was introduced.

Release 7.0.14

This command was introduced.

Release 7.3.15

The conditional installation of static route in routing table (RIB) based on object state functionality has been enhanced to use event driven notification, instead of the polling mechanism used earlier.

Usage Guidelines

A static route is appropriate when the software cannot dynamically build a route to the destination.

Static routes have a default administrative distance of 1, in which a low number indicates a preferred route. By default, static routes are preferred to routes learned by routing protocols. You can configure an administrative distance with a static route if you want the static route to be overridden by dynamic routes. For example, you could have routes installed by the Open Shortest Path First (OSPF) protocol with an administrative distance of 120. To have a static route that would be overridden by an OSPF dynamic route, specify an administrative distance greater than 120.

The routing table considers the static routes that point to an interface as “directly connected.” Directly connected networks are advertised by IGP routing protocols if a corresponding interface command is contained under the router configuration stanza of that protocol.

A static route is always associated with a VPN routing and forwarding (VRF) instance. The VRF can be the default VRF or a specified VRF. Specifying a VRF allows you to enter VRF configuration mode where you can configure a static route. If you do not specify a VRF you can configure a default VRF static route.

Use the router static command to configure static routes. To configure a static route, you must enter router static configuration mode and then enter an address family configuration mode or VRF configuration mode. See the vrf (static) command for information on configuring a static route in VRF configuration mode. After you enter an address family mode, you can enter multiple static routes. The following example shows how to configure multiple static routes in IPv4 and IPv6 address family configuration modes:


Note

You cannot create a VRF named default, but you can reference the default VRF.


Note

The conditional installation of static route in routing table (RIB) based on object state functionality has been enhanced to use event driven notification, instead of the polling mechanism used earlier. This event driven approach allows faster detection and notification of object state changes.

Examples

The following example shows how to configure the Sink node:

Router(config)#router static
Router(config-static)# address-family ipv6 unicast
Router(config-static-afi)#fccc:cc00:9000:fef1::/64 segment-routing srv6 endpoint behavior utef controller-address fccc:cc00:7::

Examples

The following example shows how to configure IPv6 unicast address family static routes: 


  Router(config)# router static
  Router(config-static)# address-family ipv6 unicast 
  Router(config-static-afi)# 2b11::327a:7b00/120 GigabitEthernet0/2/0/7
  Router(config-static-afi)# 2b11::327a:7b00/120 GigabitEthernet0/6/0/0 
  Router(config-static-afi)# 2b11::327a:7b00/120 2b11::2f01:4c
  Router(config-static-afi)# 2b11::327a:7b00/120 2b11::2f01:4d
  Router(config-static-afi)# 2b11::327a:7b00/120 2b11::2f01:4e
  Router(config-static-afi)# 2b11::327a:7b00/120 2b11::2f01:4f
  Router(config-static-afi)# 2b11::327a:7b00/120 2b11::2f01:50

router static

To enter static router configuration mode, use the router static command in mode. To remove all static route configurations and terminate the static routing process, use the no form of this command.

router static

no router static

Syntax Description

This command has no arguments or keywords.

Command Default

No static routing process is enabled.

Command Modes

Examples

The following example shows how to enter static router configuration mode: 


Router(config)# router static
Router(config-static)#

Related Commands

Command

Description

Address family static

Enters address family configuration mode.

show route

Displays the current contents of the routing table.

show route static

Displays the static routes in a routing table.

show route summary

Displays the current contents of the routing table in summary format.

Route Static

Establishes a static route.

vrf (static)

To configure a VPN routing and forwarding (VRF) instance and enter VRF configuration mode, use the vrf command in router configuration mode. To remove the VRF instance from the configuration file and restore the system to its default condition, use the no form of this command.

vrf vrf-name

no vrf vrf-name

Syntax Description

vrf-name

Name of the VRF instance. The following names cannot be used: all, default, and global.

Command Default

No default behavior or values

Command Modes

Static router configuration

Usage Guidelines

Use the vrf command to configure a VRF instance. A VRF instance is a collection of VPN routing and forwarding tables maintained at the provider edge (PE) router.

A static route is always associated with a VRF, which is entirely user configurable. Static route is unique within a VRF. A static route can point to a next-hop interface, next-hop IP address, or both, which can be resided in the same VRF configured for the static route or in a different VRF. For example, routes 172.168.40.0/24 and 172.168.50.0/24 are configured as follows: 

router static
vrf vrf_A
address ipv4 unicast
172.168.40.0/24 loopback 1
172.168.50.0/24 vrf vrf_B 192.168.1.2
Routes 172.168.40.0/24 and 172.168.50.0/24 belong to vrf_A. Route 172.168.50.0/24 is not installed in vrf_A until next-hop 192.168.1.2 (a vrf_B route) is reachable.

If you are configuring a default VRF route, you do not need to enter VRF configuration mode. For example, routes 192.168.1.0/24 and 192.168.2.0/24 are configured as follows: 


  router static
   address ipv4 unicast
    192.168.1.0/24 loopback 5
    192.168.2.0/24 10.1.1.1

Routes 192.168.1.0/24 and 192.168.2.0/24 are default VRF routes.


Note

You cannot create a VRF named default, but you can reference the default VRF.

Examples

The following example shows how to configure a VRF instance and enter VRF configuration mode: 


  Router(config)# router static
  Router(config-static)# vrf vrf-1
  Router(config-static-vrf)# 

Related Commands

Command

Description

Address family static

Enters address family configuration mode and allows you to configure a static route.