Configuration Groups

A configuration group includes a series of configuration statements that can be used in multiple hierarchical levels in the router configuration tree. By using regular expressions in a configuration group,you can create generic commands that can be applied in multiple instances.

This module describes how to configure and use command line interface (CLI) configuration groups.

Configuration Groups Overview

Configuration groups provide the ability to minimize repetitive configurations by defining a series of configuration statements in a configuration group, and then applying this group to multiple hierarchical levels in the router configuration tree.

Configuration groups utilize regular expressions that are checked for a match at multiple submodes of the configuration tree based on where the group is applied within the hierarchy. If a match is found at a configuration submode, the corresponding configuration defined in the group is inherited within the matched submode.

Configuration groups also provide an auto-inheritance feature. Auto-inheritance means that any change done to a CLI configuration group is automatically applied to the configuration in any matched submodes that have an apply-group at that hierarchical level. This allows you to make a configuration change or addition once, and have it applied automatically in multiple locations, depending on where you have applied the configuration group.

Guidelines and Restrictions for Configurations Group

These are the restrictions for configuration groups:

  • Configuration groups aren’t supported in administration configurations. And corresponding apply-groups aren’t supported in administration configurations.

  • Use of preconfigured interfaces in configuration groups isn’t supported.

  • Downgrading from an image that supports configuration groups to an image that doesn’t support them isn’t supported.

  • Access lists (ACLs), Quality of Service (QoS) and route policy configurations don’t support the use of configuration groups. Configurations such as these aren’t valid: 

group g-not-supported ipv4 access-list ... 
! 
ipv6 access-list ... 
! 
ethernet-service access-list ... 
! 
class-map ... 
! 
policy-map ... 
! 
route-policy ... 
! 
end-group

You can, however, reference such configurations, as shown in this example: 

group g-reference-ok 
 router bgp 6500 
  neighbor 7::7 
   remote-as 65000 
   bfd fast-
   detect 
   update-source Loopback300 
   graceful-restart disable 
   address-family ipv6 
   unicast 
    route-policy test1 in 
    route-policy test2 
    out 
    soft-reconfiguration inbound always 
   ! 
 ! 
! 

interface Bundle-Ether1005 
 bandwidth 10000000 
 mtu 9188 
 service-policy output input_1 
 load-interval 30 
! 
end-group

  • Configuration groups are not available through the XML interface.

  • Commands that require a node identifier for the location keyword aren’t supported. For example, this configuration isn’t supported: 

    lpts pifib hardware police location 0/0/CPU0

  • Overlapping regular expressions within a configuration group for the same configuration aren’t supported. For example: 

    group G-INTERFACE interface 'gig.*a.*' 
mtu 1500 
! 
interface 'gig.*e.* ' mtu 2000 
! 
end-group
 
interface gigabitethernet0/4/1/0 apply-group G-INTERFACE

This configuration isn’t permitted because it can’t be determined whether the interface gigabitethernet0/4/1/0 configuration inherits mtu 1500 or mtu 2000 . Both expressions in the configuration group match gigabit ethernet 0/4/1/0.

  • Up to eight configuration groups are permitted on one apply-group command.

  • Use a multiline configuration style to configure configuration groups (like group or apply-group commands) by entering each configuration mode in a separate line, one configuration per line. Using a multiline configuration style helps configuration properties to be fully inherited and provides better readability during troubleshooting.

An example for a correct configuration style is: 

Router# configure 
Router(config)# router isis IGP 
Router(config-isis)# interface Ten 0/4/0/0 
Router(config-isis-if) # address-family ipv4 unicast 
Router(config-isis-if-af) # metric 123

Create a Configuration Group

The steps of creating a configuration group involves two sub-tasks:

  • Creating a configuration group

  • Applying a configuration group

Use the following steps to create a configuration group:

Procedure

Step 1

Enter global configuration mode.

Example:

Router# configure

Step 2

Specify a name for a configuration group and enter group configuration mode to define the group.The group-name argument can have up to 32 characters and cannot contain any special characters.

Example:

Router(config)# group g-interf

Step 3

Specify the configuration statements that you want included in this configuration group. For more information regarding the use of regular expressions, see Regular Expressions in Configuration Groups. This example is applicable to all Gigabit Ethernet interfaces.

Example:

Router(config-GRP)# interface 'GigabitEthernet.*' 
Router(config-GRP-if)# mtu 1500

Step 4

Complete the configuration of a configuration group and exits to global configuration mode.

Example:

Router(config-GRP-if)# end-group

Step 5

Add the configuration of the configuration group into the router configuration applicable at the location that the group is applied. Groups can be applied in multiple locations, and their effect depends on the location and context. The MTU value from the group g-interf is applied to the interface GigabitEthernet0/2/0/0. If this group is applied in global configuration mode, the MTU value is inherited by all Gigabit Ethernet interfaces that don't have an MTU value configured.

Example:

Router(config)# interface GigabitEthernet0/2/0/0 
Router(config-if)# apply-group g-interf

Simple Configuration Group:Example

Procedure

This example shows how to use configuration groups to add a global configuration to the system:

Example:

Router(config)# group g-logging 
Router(config-GRP)# logging trap notifications 
Router(config-GRP)# logging console debugging 
Router(config-GRP)# logging monitor debugging 
Router(config-GRP)# logging buffered 10000000 R
Router(config-GRP)# end-group 
Router(config)# apply-group g-logging

When this configuration is committed, all commands contained in the g-logging configuration group are committed.

Configuration Group Applied to Different Places:Example

Configuration groups can be applied to different locations, and their effect depends on the context within which they are applied.

Procedure

Step 1

Consider this configuration group:

Example:

Router(config)# group g-interfaces 
Ruter(config-GRP)# interface 'FastEthernet.*' 
Router(config-GRP-if)# mtu 1500 
Router(config-GRP-if)# exit 
Router(config-GRP)# interface 'GigabitEthernet.*' 
Router(config-GRP-if)# mtu 1000 
Router(config-GRP-if)# exit 
Router(config-GRP)# interface 'POS.*' 
Router(config-GRP-if)# mtu 2000 
Router(config-GRP-if)# end-group

Step 2

This group can be applied to Fast Ethernet, Gigabit Ethernet or POS interfaces, and in each instance the applicable MTU is applied. For instance, in this example, the Gigabit Ethernet interface is configured to have an MTU of 1000:

Example:

Router(config)# interface GigabitEthernet0/2/0/0 
Router(config-if)# apply-group g-interfaces 
Router(config-if)# ipv4 address 192.0.2.1

Step 3

In this example, the Fast Ethernet interface is configured to have an MTU of 1500:

Example:

Router(config)# interface FastEthernet0/2/0/0 
Router(config-if)# apply-group g-interfaces 
Router(config-if)# ipv4 address 192.0.2.1

Step 4

The same configuration group is used in both cases, but only the applicable configuration statements are used.

Verify Configuration Groups Creation

To verify the router configuration using configuration groups:

Procedure

Step 1

Use the show running-config group command to display the contents of a specific or all configured configuration groups.

Example:

Router# show running-config group 
group g-int-ge 
 interface 'GigabitEthernet.*' 
  mtu 1000 
   negotiation auto 
 !

Step 2

Use the show running-confi g command to display the running configuration. Any applied groups are displayed. There is no indication as to whether these configuration groups affect the actual configuration or not. In this example, although the group G-INTERFACE-MTU is applied to POS0/4/1/1, the configured MTU value is 2000 and not 1500. This happens if the command mtu 2000 is configured directly on the interface. An actual configuration overrides a configuration group configuration if they are the same.

Example:

Router# show running-config 
group G-INTERFACE-MTU 
 interface ‘POS.*’ 
  mtu 1500 
 ! 

end-group 

interface POS0/4/1/0 
 apply-group G-INTERFACE-MTU
! 

interface POS0/4/1/1 
 apply-group G-INTERFACE-MTU 
  mtu 2000 
 !

Step 3

You can use the show running-config inheritance command to check the inherited configuration whereever a configuration group has been applied.

Example:

Router# show running-config inheritance 
. 
. 
group G-INTERFACE-MTU 
 interface ‘POS.*’ mtu 1500 
 ! 
end-group 
. 
. 

interface POS0/4/1/0 
 ## Inherited from group G-INTERFACE-MTU 
  mtu 1500 
! 

interface POS0/4/1/1 
 mtu 2000 
! 
.
.

Step 4

Use the show running-config interfcae inheritance command to verify inherited configuration for a specific configuration command.

Example:

Router# show running-config interface pos0/4/1/0 inheritance [detail] 


interface POS0/4/1/0 
 ## Inherited from group G-INTERFACE-MTU 
  mtu 1500

Priority Inheritance for Configuration Groups

The configuration groups inheritance is supported according to the priority.

Apply groups priority inheritance helps configuration groups handle common configuration statements between groups. When multiple configuration groups have common configuration statements, the inheritance priority is that configuration statements present in inner groups have precedence over configuration statements present in outer groups. The tiebreaker is determined by the system order (lexicographical) of the regular expressions. User-defined order of commands isn’t accepted.

For example, a configuration statement in configuration group ONE has precedence over any other group. A configuration statement in configuration group SEVEN is used only if it’s not contained in any other group. Within a configuration group, inheritance priority is the lengthiest match. 

apply-group SIX SEVEN 
            router ospf 0 
            apply-group FOUR FIVE 
            area 0 
                apply-group THREE 
                interface GigabitEthernet 0/0/0/0 
                 apply-group ONE TWO 
        ! 
       ! 
      !

This example states two scenarios. Inner most group (apply-group ONE TWO) has the highest priority.

Case 1

In the first scenario it shows which group gets the first priority. The example states which group is applied between different configuration groups (different groups- nothing in common between them). While applying the group one (ONE TWO), all the seven groups that matches to the interface interface GigabitEthernet 0/0/0/0 are applied.

Case 2

In the case when all these groups (as mentioned in the example) have the same (common) configuration, group one is active. The apply-group ONE TWO is active. If group ONE is deleted, then group TWO is active.


Note

From the Cisco IOS XR Software Release 6.3.1 onwards, you’re able to enter the configuration group definition, apply-group and exclude-group command in any order as long as the entire commit has all the group definitions needed.

Exclude-group command can be used to exclude a configuration group (or groups) to be inherited by the router configuration, in the appropriate configuration mode.

Configuration Group Precedence

Procedure

Step 1

When similar configuration statements are contained in multiple configuration groups, groups applied in inner configuration modes take precedence over groups applied in outer modes. This example shows two configuration groups that configure different cost values for OSPF.

Example:

 Router(config)# group g-ospf2 
Router(config-GRP)# router ospf '.*' 
Router(config-GRP-ospf)# area '.*' 
Router(config-GRP-ospf-ar)# cost 2 
Router(config-GRP-ospf-ar)# end-group 

Router(config)# group g-ospf100 
Router(config-GRP)# router ospf '.*' 
Router(config-GRP-ospf)# area '.*' 
Router(config-GRP-ospf-ar)# cost 100 
Router(config-GRP-ospf-ar)# end-group

Step 2

If these configuration groups are applied as follows, the cost 2 specified in g-ospf2 is inherited by OSPF area 0 because the group is applied in a more inner configuration mode. In this case, the configuration in group g-ospf100 is ignored.

Example:

Router(config)# router ospf 0 
Router(config-ospf)# apply-group g-ospf100 
Router(config-ospf)# area 0 
Router(config-ospf-ar)# apply-group g-ospf2

Precedence for Local Configuration

This example illustrates that local configurations take precedence when there is a discrepancy between a local configuration and the configuration inherited from a configuration group.

Procedure

Step 1

Configure a local configuration in a configuration submode with an access list:

Example:

Router# show running interface gigabitEthernet 0/0/0/39 

interface GigabitEthernet0/0/0/39 
 ipv4 access-group smany ingress 
 ipv4 access-group smany egress 
! 
Router# show running interface gigabitEthernet 0/0/0/38 
 interface GigabitEthernet0/0/0/38 
! 
Router# show running ipv4 access-list smany 
ipv4 access-list smany 
 10 permit ipv4 any any 
! 

Router# show running ipv4 access-list adem 
ipv4 access-list adem 
 10 permit ipv4 21.0.0.0 0.255.255.255 host 55.55.55.55 
 20 deny ipv4 any any 
!

Step 2

Configure and apply the access list group configuration:

Example:

Router# show running group acref 
group acref 
interface 'GigabitEthernet0/0/0/3.*' 
 ipv4 access-group adem ingress 
 ipv4 access-group adem egress 
! 
end-group 

 
Router# show running | inc apply-group 

Building configuration... 
apply-group isis l2tr isis2 mpp bundle1 acref

Step 3

Check the concise and inheritance views for the matching interface where the access list reference is configured locally:

Example:

Router# show running interface gigabitEthernet 0/0/0/39 
 interface GigabitEthernet0/0/0/39 ipv4 access-group smany ingress ipv4 access-group smany egress 
! 

Router# show running inheritance interface gigabitEthernet 0/0/0/39 
interface GigabitEthernet0/0/0/39 ## Inherited from group l2tr 
mtu 1500 
 ipv4 access-group smany ingress 
 ipv4 access-group smany egress	<< no config inherited, local config prioritized 
! 
Router# show running interface gigabitEthernet 0/0/0/38 
interface GigabitEthernet0/0/0/38 
! 
Router# show running inheritance interface gigabitEthernet 0/0/0/38 
interface GigabitEthernet0/0/0/38 ## Inherited from group l2tr 
mtu 1500 
## Inherited from group acref ipv4 
access-group adem ingress
## Inherited from group acref 
 ipv4 access-group adem egress 
!

Step 4

Use a traffic generator to verify that the traffic pattern for interface GigabitEthernet0/0/0/39 gets acted on by the access list in the local configuration (smany) and not according to the inherited referenced access list (adem).

Automatic Inheritance of Modifications to Configuration Group

Procedure

Step 1

When you make changes to a configuration group that is committed and applied to your router configuration,the changes are automatically inherited by the router configuration. For example, assume that this configuration is committed:

Example:

group g-interface-mtu 
 interface ‘POS.*’ 
  mtu 1500 
 ! 
end-group 
 
interface POS0/4/1/0 
 apply-group g-interface-mtu 
!

Step 2

Now you change the configuration group as in this example:

Example:

Router(config)# group g-interface-mtu 
Router(config-GRP)# interface 'POS.*' 
Router(config-GRP-if)# mtu 2000 
Router(config-GRP-if)# end-group

When this configuration group is committed, the MTU configuration for interface POS0/4/1/0 is automatically updated to 2000.

Regular Expressions in Configuration Groups

Regular expressions are used in configuration groups to make them widely applicable. Portable Operating System Interface for UNIX (POSIX) 1003.2 regular expressions are supported in the names of configuration statements. Single quotes must be used to delimit a regular expression.

Restrictions for Regular Expressions in Configuration Groups

The following are the restrictions for regular expressions:

  • Some regular expressions aren’t supported within groups. For example, ‘?’, ‘|’ and ‘$,’ aren’t supported within groups. Also some characters such as /d and /w aren’t supported.

  • The choice operator “|” to express multiple match expressions within a regular expression isn’t supported. For example, these expressions aren’t supported:

    Gig.*|Gig.*\..*—To match on either Gigabit Ethernet main interfaces or Gigabit Ethernet subinterfaces.

    Gig.*0/0/0/[1-5]|Gig.*0/0/0/[10-20]—To match on either Gig.*0/0/0/[1-5] or Gig.*0/0/0/[10-20].

    'TenGigE.*|POS.*—To match on either TenGigE.* or POS.*

  • Not all POSIX regular expressions are supported.

  • If the system can’t determine from the regular expression what the configuration should be, the expression is not considered valid.

  • The regular expression ‘.*’ isn’t allowed when referring to an interface identifier. You must begin the regular expression for an interface identifier with an unambiguous word, followed by the regular expression.

Regular Expressions for Interface Identifiers

Configuration groups don’t accept exact interface identifiers. You must use a regular expression to identify a group of interfaces that are applicable to the configuration group. The regular expression ‘.*’ isn’t allowed. You must begin the regular expression for an interface identifier with an unambiguous word, followed by the regular expression. For example, to configure Gigabit Ethernet interfaces, use the regular expression 'GigabitEthernet.*'.

Procedure

Step 1

Display a list of available interface types for your router configuration, use the interface? at the configuration group prompt:

Example:

Router(config-GRP)# interface ? 
ATM	'RegExp': ATM Network Interface(s) 
BVI	'RegExp': Bridge-Group Virtual Interface Bundle-Ether	
'RegExp': Aggregated Ethernet interface(s) Bundle-POS
'RegExp': Aggregated POS interface(s) 
GigabitEthernet 'RegExp': GigabitEthernet/IEEE 802.3 interface(s) IMA	
'RegExp': ATM Network Interface(s) 
Loopback	'RegExp': Loopback interface(s) 
MgmtEth	'RegExp': Ethernet/IEEE 802.3 interface(s) Multilink	
'RegExp': Multilink network interface(s) Null	
'RegExp': Null interface 
POS	'RegExp': Packet over SONET/SDH network interface(s) PW-Ether	
'RegExp': PWHE Ethernet Interface 
PW-IW	'RegExp': PWHE VC11 IP Interworking Interface Serial	
'RegExp': Serial network interface(s) 
tunnel-ip	'RegExp': GRE/IPinIP Tunnel Interface(s) 
tunnel-mte	'RegExp': MPLS Traffic Engineering P2MP Tunnel interface(s) tunnel-te	'
RegExp': MPLS Traffic Engineering Tunnel interface(s) tunnel-tp	
'RegExp': MPLS Transport Protocol Tunnel interface

Step 2

To specify a subinterface, prefix the expression with the characters \. (Backslash period). For example, use interface 'GigabitEthernet.*\..*' to configure all Gigabit Ethernet subinterfaces. You can specify Layer 2 transport interfaces or point-to-point interfaces as shown in this example:

Example:


group g-l2t 
 interface 'Gi.*\..*' l2transport 
. 
. 
end-group group g-ptp 
 interface 'Gi.*\..*' point-to-point 
. 
. 
end-group

Note

 

Although you’re required to enter only enough characters for the interface type to be unique, it’s recommended that you enter the entire phrase. All interface types used in regular expressions are case-sensitive.

Regular Expressions for an OSPF Configuration

Procedure

Step 1

Exact router process names and OSPF areas can’t be used. You must use a regular expression to specify a process name or group of OSPF areas. To specify that the OSFP area can be either a scalar value or an IP address, use the regular expression ‘.*’, as in this example:

Example:

group g-ospf router ospf '.*' area '.*' 
 mtu-ignore enable 
! 
! 
end-group

Step 2

Use the expression '\.', to specify that the OSPF area must be an IP address.

Example:

group g-ospf-ipaddress router ospf '.*\..*\..*\..*' area '.*' 
 passive enable 
! 
! 
end-group

Step 3

Use the expression '1.*', to specify that the OSPF area must be a scalar value.

Example:

group g-ospf-match-number router ospf '.*' 
 area '1.*' passive enable 
! 
! 
end-group

Regular Expressions for ISIS Configuration

Procedure

Step 1

This example shows the definition of a configuration group for configuring Gigabit Ethernet interfaces with ISIS routing parameters, using regular expressions for the exact interface:

Example:

RP/0/RSP0/CPU0:router(config)# group g-isis-gige 
RP/0/RSP0/CPU0:router(config-GRP)# router isis '.*' 
RP/0/RSP0/CPU0:router(config-GRP-isis)# interface 'GigabitEthernet.*' 
RP/0/RSP0/CPU0:router(config-GRP-isis-if)# lsp-interval 20 
RP/0/RSP0/CPU0:router(config-GRP-isis-if)# hello-interval 40 
RP/0/RSP0/CPU0:router(config-GRP-isis-if)# address-family ipv4 unicast 
RP/0/RSP0/CPU0:router(config-GRP-isis-if-af)# metric 10 
RP/0/RSP0/CPU0:router(config-GRP-isis-if-af)# end-group 
RP/0/RSP0/CPU0:router(config)#

Step 2

To illustrate the use of this configuration group, assume that you want to configure these Gigabit Ethernet interfaces with the ISIS routing parameters:

Example:

router isis green 
 interface GigabitEthernet0/0/0/0 
 lsp-interval 20 
 hello-interval 40 
 address-family ipv4 unicast 
 metric 10 
 ! 
! 

interface GigabitEthernet0/0/0/1 
lsp-interval 20 
hello-interval 40 
address-family ipv4 unicast 
metric 10 
 ! 
! 

interface GigabitEthernet0/0/0/2 
lsp-interval 20 
hello-interval 40 
address-family ipv4 unicast 
metric 10 
 ! 
! 

interface GigabitEthernet0/0/0/3 
lsp-interval 20 
hello-interval 40 
address-family ipv4 unicast 
metric 10 
  ! 
 ! 
!

Step 3

There are three possible ways to use the configuration group to configure these interfaces. The first is by applying the group within the interface configuration, as shown here:

Example:

router isis green 
 interface GigabitEthernet0/0/0/0  
 apply-group g-isis-gige 
 ! 
! 
interface GigabitEthernet0/0/0/1 
apply-group g-isis-gige 
! 

! 
interface GigabitEthernet0/0/0/2 
 apply-group g-isis-gige 
! 

! 
interface GigabitEthernet0/0/0/3 
apply-group g-isis-gige 
 ! 

!

Step 4

In this situation, only the interfaces to which you apply the configuration group inherit the configuration.The second way to configure these interfaces using the configuration group is to apply the configuration group within the router isis configuration, as shown here:

Example:

router isis green 
apply-group g-isis-gige 
interface GigabitEthernet0/0/0/0 
! 
interface GigabitEthernet0/0/0/1 
! 
interface GigabitEthernet0/0/0/2 
! 
interface GigabitEthernet0/0/0/3 
 ! 
!

Step 5

In this way, any other Gigabit Ethernet interfaces that you configure in the ISIS green configuration also inherit these configurations. The third way to configure these interfaces using the configuration group is to apply the group at the global level as shown here:

Example:

 apply-group g-isis-gige 
router isis green 
interface GigabitEthernet0/0/0/0 
 ! 
interface GigabitEthernet0/0/0/1 
! 
interface GigabitEthernet0/0/0/2 
! 
interface GigabitEthernet0/0/0/3 
 ! 
!

In this example, the configuration of the group is applied to all Gigabit Ethernet interfaces configured for ISIS.

Regular Expressions for a BGP AS

Exact BGP AS values can’t be used in configuration groups. Use a regular expression to specify either AS plain format, or AS dot format as in the format X.Y. To match AS plain format instances, use a simple regular expression.

Procedure

Use two regular expressions separated by a dot, to match AS dot format instances as shown in this example:

Example:

group g-bgp router 
bgp '*'.'*' 
address-family ipv4 unicast 
! 
! 
end-group

Regular Expressions for ANCP

Exact Access Node Control Protocol (ANCP) sender-name identifiers cannot be used in configuration groups. Because the sender name argument can be either an IP address or a MAC address, you must specify in the regular expression which one is being used. Specify an IP address as '.*\..*\..*\..*'; specify a MAC address as '.*\..*\..*'.

Resolving Regular Expressions to a Uniform Type

Procedure

Regular expressions must resolve to a uniform type. This is an example of an illegal regular expression:

Example:

group g-invalid 
 interface ‘.*’ 
  bundle port-priority 10 
 ! 
interface ‘.*Ethernet.*’ 
 bundle port-priority 10 
! 
end-group

In this example, the bundle command is supported for interface type GigabitEthernet but not for interface type ‘FastEthernet’. The regular expressions ‘.*’ and ‘.*Ethernet.*’ match both GigabitEthernet and FastEthernet types. Because the bundle command isn’t applicable to both these interface types, they don’t resolve to a uniform type and therefore the system doesn’t allow this configuration.

Overlapping Regular Expressions

Regular expressions are used in the names of configuration statements within a configuration group. This permits inheritance by the configuration when applied to matching names. Single quotes are used to delimit the regular expression. Overlapping regular expression within a configuration group for the same configuration is permitted.

Procedure

Step 1

The example, given below, illustrates the process of creating and applying multiple configuration groups:

Example:

Router(config)#group FB_flexi_snmp 
Router(config-GRP)# snmp-server vrf '.*' 
Router(config-GRP-snmp-vrf)# host 10.0.0.1 traps version 2c group_1 
Router(config-GRP-snmp-vrf)# host 10.0.0.1 informs version 2c group_1 
Router(config-GRP-snmp-vrf)# context group_1 
Router(config-GRP-snmp-vrf)#commit
Router(config-GRP-snmp-vrf)#root 
Router(config)#snmp-server vrf vrf1 
Router(config-snmp-vrf)#snmp-server vrf vrf10 
Router(config-snmp-vrf)#! 
Router(config-snmp-vrf)#snmp-server vrf vrf100 
Router(config-snmp-vrf)#commit
Router(config-snmp-vrf)#root  
Router(config)#apply-group FB_flexi_snmp 
Router(config)#do sh running-config group  
group FB_flexi_snmp
 snmp-server vrf '.*' 
  host 10.0.0.1 traps version 2c group_1 
  host 10.0.0.1 informs version 2c group_1 
  context group_1 
 ! 
end-group 

apply-group FB_flexi_snmp 
snmp-server vrf vrf1 
! 
snmp-server vrf vrf10 
! 
snmp-server vrf vrf100 
! 

Router#show running-config inheritance detail 

group FB_flexi_snmp 
 snmp-server vrf 
 '.*' 
  host 10.0.0.1 traps version 2c group_1 
  host 10.0.0.1 informs version 2c group_1 
  context group_1 
  ! 
end-group 

snmp-server vrf vrf1 

## Inherited from group FB_flexi_snmp host 10.0.0.1 traps version 2c group_1 ## Inherited from group FB_flexi_snmp host 10.0.0.1 informs version 2c group_1 ## Inherited from group FB_flexi_snmp context group_1 

! 

snmp-server vrf vrf10 

## Inherited from group FB_flexi_snmp host 
10.0.0.1 traps version 2c group_1 
## Inherited from group FB_flexi_snmp host 
10.0.0.1 informs version 2c group_1 
## Inherited from group FB_flexi_snmp 
context group_1 
! 

snmp-server vrf vrf100 
## Inherited from group FB_flexi_snmp 
host 10.0.0.1 traps version 2c group_1 
## Inherited from group FB_flexi_snmp 
host 10.0.0.1 informs version 2c group_1 ## 
Inherited from group FB_flexi_snmp context group_1

Step 2

The example given below demonstrates the regular expression. In this example snmp-server vrf '.*’ and snmp-server vrf '[\w]+ are two different regular expressions.

Example:

group FB_flexi_snmp 
snmp-server vrf 
'.*’ 
host 10.0.0.1 traps version 2c group_1 
host 10.0.0.1 informs version 2c group_1 
context group_1 
! 

snmp-server vrf '[\w]+’ 
host 172.16.0.1 traps version 2c group_2 
host 172.16.0.1 informs version 2c group_2 
context group_2 
! 
end-group

Step 3

This individual regular expression gets combined to all the three expressions - snmp-server vrf vrf1, snmp-server vrf vrf10 and snmp-server vrf vrf100 as given below.

Example:

apply-group FB_flexi_snmp 
snmp-server vrf vrf1 
! 
snmp-server vrf vrf10 
! 
snmp-server vrf vrf100 
!

Step 4

In a configuration group, there can be instances of regular expressions overlap. In such cases, the regular expression with the highest priority is activated and inherited, when applied. It has that regular expression, which comes first in the lexicographic order that has the highest priority. The following example shows how to use overlapping regular expressions and how the expression with higher priority is applied:

Example:

group FB_flexi_snmp 
snmp-server vrf 
'.*’ 
 host 10.0.0.1 traps version 2c group_1 
 host 10.0.0.1 informs version 2c group_1 
 context group_1 
! 

snmp-server vrf '[\w]+’ 

 host 172.16.0.1 traps version 2c group_2 
 host 172.16.0.1 informs version 2c group_2 
 context group_2 
! 
end-group

Step 5

The expression shown below has the highest priority:

Example:

group FB_flexi_snmp snmp-server vrf '.*’ 

host 10.0.0.1 traps version 2c group_1 
host 10.0.0.1 informs version 2c group_1 
context group_1

Step 6

The examples given above, show two different regular expression snmp-server vrf '.*’ and snmp-server vrf '[\w]+'. The expression below, shows how these two expressions get merged together:

Example:

apply-group FB_flexi_snmp 
snmp-server vrf vrf1 
! 
snmp-server vrf vrf10 
! 
snmp-server vrf vrf100 
!

Step 7

Any change in a regular expression with lower priority will not affect the inheritance.Any changes made to an existing regular expression, which is of less (non-top) priority, it will not have any effect on the inheritance.

Example:

snmp-server vrf '[\w]+’ 
host 172.16.0.1 traps version 2c group_2 
host 172.16.0.1 informs version 2c group_2 
context group_2

Step 8

The expression with the higher priority gets inherited, as shown below:

Example:

group FB_flexi_snmp 
snmp-server vrf 
'.*’ 
host 10.0.0.1 traps version 2c group_1 
host 10.0.0.1 informs version 2c group_1 
context group_1

Configuration Group Inheritance with Regular Expressions

The following guidelines apply to configuration group inheritance with regular expressions:

  • Local configuration has precedence over configuration group

    An explicit configuration takes precedence over a configuration applied from a configuration group. For example, assume that this configuration is running on the router: 

    router ospf 100 
 packet-size 1000 
!

    You configure this configuration group, apply it, and commit it to the configuration. 

    Router(config)# group g-ospf 
Router(config-GRP)# router ospf '.*' 
Router(config-GRP-ospf)# nsf cisco 
Router(config-GRP-ospf)# packet-size 3000 
Rrouter(config-GRP-ospf)# end-group 
Router(config)# apply-group g-ospf

    The result is effectively this configuration: 

    router ospf 100  
 packet-size 1000 
 nsf cisco

    Note that packet-size 3000 is not inherited from the configuration group because the explicit local configuration has precedence.

  • Compatible configuration is inherited

    The configuration in the configuration group must match the configuration on the router to be inherited.If the configuration does not match,it is not inherited. For example, assume that this configuration is running on the router: 

    router ospf 100 
 auto-cost 
  disable 
!

    You configure this configuration and commit it to the configuration. 

    Router(config)# group g-ospf 
Router(config-GRP)# router ospf '.*' 
Router(config-GRP-ospf)# area '.*' 
Router(config-GRP-ospf-ar)# packet-size 2000 
Router(config-GRP-ospf)# end-group 
Router(config)# apply-group g-ospf 
Router(config)# router ospf 200 
Router(config-ospf)# area 1

    The result is effectively this configuration: 

    router ospf 100 
 auto-cost 
 disable 

router ospf 200 
 area 1 
 packet-size 2000

    The packet size is inherited by the ospf 200 configuration, but not by the ospf 100 configuration because the area is not configured.

Layer 2 Transport Configuration Group

This example shows how to configure and apply a configuration group with Layer 2 transport subinterfaces: 

Router(config)# group g-l2trans-if 
Router(config-GRP)# interface 'TenGigE.*\..*' l2transport 
Router(config-GRP)# mtu 1514 
Router(config-GRP)# end-group 
Router(config)# interface TenGigE0/0/0/0.1 l2transport 
Router(config-if)# apply-group g-l2trans-if

When this configuration is committed, the Ten Gigabit Ethernet interface 0/0/0/0.1 inherits the 1514 MTU value. This is the output displayed from the show running-config inheritence command for the Ten Gigabit Ethernet interface: 

interface TenGigE0/0/0/0.1 l2transport 
 ## Inherited from group g-l2trans-if 
 mtu 1514 
!

Use Cases of Configuration Groups

Basic Configuration

This example shows that the Media Access Control (MAC) accounting configuration from the gd21 configuration group is applied to all Gigabit Ethernet interfaces in slot 2, ports 1 to 9.

Procedure

Step 1

Configure the configuration group that configures MAC accounting:

Example:

Router# show running group gd21 

group gd21 
interface 'GigabitEthernet0/0/0/2[1-9]' 
description general interface inheritance check 
load-interval 30 
mac-accounting ingress 
mac-accounting egress 
! 
end-group

Step 2

Check that the corresponding apply-group is configured in global configuration or somewhere in the hierarchy:

Example:

Router# show running | in apply-group gd21 
Building configuration... 
apply-group gd21

Step 3

Check the concise local view of the configuration of some of the interfaces:

Example:

Router# show running interface 
interface GigabiEthernet0/0/0/21 
! 
interface GigabitEthernet0/0/0/22 
!

Step 4

Verify that the match and inheritance occur on these interfaces:

Example:

Router# show running inheritance interface 
interface GigabitEthernet0/0/0/21 ## Inherited from group gd21 
description general interface inheritance check ## Inherited from group gd21 
load-interval 30 
## Inherited from group gd21 mac-accounting ingress 
## Inherited from group gd21 mac-accounting egress 
! 

Interface GigabitEthernet0/0/0/22 
## Inherited from group gd21 
description general interface 
inheritance check 
## Inherited from group gd21 
load-interval 30 
## Inherited from group gd21 
mac-accounting ingress 
## Inherited from group gd21 
mac-accounting egress 
! 

!

Step 5

Verify that the inherited configuration actually takes effect:

Example:

Router# show mac gigabitEthernet0/0/0/21 


GigabitEthernet0/0/0/21 
 Input (96 free) 
 6c9c.ed35.90fd: 1271 packets, 98426 bytes 
 Total: 1271 packets, 98426 bytes 

Output (96 free) 
 6c9c.ed35.90fd:	774 packets, 63265 bytes 
 Total: 774 packets, 63264 bytes

Interface MTU Settings for Different Interface Types

This example shows that an MTU value is configured on different interface types.

Procedure

Step 1

Configure an interface MTU configuration group and apply this group:

Example:

Router# show running group l2tr 

group l2tr 
interface 'GigabitEthernet0/0/0/3.*' 
mtu 1500 
! 
interface 'GigabitEthernet0/0/0/9\..*' 
mtu 1400 
! 
interface 'GigabitEthernet0/0/0/9\..*' l2transport 
mtu 1400 
! 
end-group 

Router# show running | inc apply-group 
Building configuration... 
apply-group l2tr

Step 2

Check the concise view and the inheritance view of the various interfaces:

Example:

 Router# show running interface gigabitEthernet0/0/0/30 
interface GigabitEthernet0/0/0/30 
! 
## Inherited from group l2tr mtu 1500 

! 

Router# show running interface gigabitEthernet0/0/0/9.800 
interface GigabitEthernet0/0/0/9.800 encapsulation dot1q 800 
! 
Router# show running inheritance interface gigabitEthernet0/0/0/9.800 
interface GigabitEthernet0/0/0/9.800 ## Inherited from group l2tr 
mtu 1400 encapsulation dot1q800 
! 
Router# show running inheritance interface gigabitEthernet0/0/0/9.800 

interface GigabitEthernet0/0/0/9.250 l2transport encapsulation dot1q250 
## Inherited from group l2tr mtu 1400 
!

Step 3

Verify that the correct values from the group do take effect:

Example:

Router# show interface gigabitEthernet 0/0/0/30 
GigabitEthernet0/0/0/30 is down, line protocol is down Interface state transitions: 0 
Hardware is GigabitEthernet, address is 0026.9824.ee56 (bia 0026.9824.ee56) Internet address is Unknown 
MTU 1500 bytes, BW 1000000 Kbit (Max: 1000000 Kbit) 
 reliability 255/255, txload 0/255, rxload 0/255 
Encapsulation ARPA, 
Full-duplex, 1000Mb/s, link type is force-up 
output flow control is off, input flow control is off loopback not set, 
Last input never, output never 
Last clearing of "show interface" counters never 
5 minute input rate 0 bits/sec, 0 packets/sec 
5 minute output rate 0 bits/sec, 0 packets/sec 
 0 packets input, 0 bytes, 0 total input drops 
 0 drops for unrecognized upper-level protocol Received 0 broadcast packets, 0 multicast packets 
 0 runts, 0 giants, 0 throttles, 0 parity  
 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 
 0 packets output, 0 bytes, 0 total output drops Output 0 broadcast packets, 0 multicast packets 
 0 output errors, 0 underruns, 0 applique, 0 resets 
 0 output buffer failures, 0 output buffers swapped out 
Router# show interface gigabitEthernet 0/0/0/9.801 
GigabitEthernet0/0/0/9.801 is up, line protocol is up Interface state transitions: 1 
Hardware is VLAN sub-interface(s), address is 0026.9824.ee41 Internet address is Unknown 
MTU 1400 bytes, BW 1000000 Kbit (Max: 1000000 Kbit) reliability 255/255, txload 0/255, rxload 0/255 
Encapsulation 802.1Q Virtual LAN, VLAN Id 801, loopback not set, Last input never, output never 
Last clearing of "show interface" counters never 
5 minute input rate 0 bits/sec, 0 packets/sec 
5 minute output rate 0 bits/sec, 0 packets/sec 
 0 packets input, 0 bytes, 0 total input drops 
 0 drops for unrecognized upper-level protocol 
 Received 0 broadcast packets, 0 multicast packets 
 0 packets output, 0 bytes, 0 total output drops 
 Output 0 broadcast packets, 0 multicast packets 

Router# show interface gigabitEthernet 0/0/0/9.250 

GigabitEthernet0/0/0/9.250 is up, line protocol is up 
 Interface state transitions: 1 
 Hardware is VLAN sub-interface(s), address is 0026.9824.ee41 
 Layer 2 Transport Mode 
 MTU 1400 bytes, BW 1000000 Kbit (Max: 1000000 Kbit) 
 reliability Unknown, txload Unknown, rxload Unknown 
Encapsulation 802.1Q Virtual LAN, 
 Outer Match: Dot1Q VLAN 250 
 Ethertype Any, MAC Match src any, dest any 
 loopback not set, 
Last input never, output never 
Last clearing of "show interface" counters never 
 0 packets input, 0 bytes 
 0 input drops, 0 queue drops, 0 input errors 
 0 packets output, 0 bytes 
 0 output drops, 0 queue drops, 0 output errors

ACL Referencing

This example shows how to reference access-lists on a number of interfaces using configuration groups.

Procedure

Step 1

Configure the configuration group and apply-group:

Example:

Router# show running group acref 

group acref 
interface 'GigabitEthernet0/0/0/3.*' 
 ipv4 access-group adem ingress 
 ipv4 access-group adem egress 
! 
end-group
Router# show running | inc apply-group 
Building configuration... 
apply-group isis l2tr isis2 mpp bundle1 acref

Step 2

Check the concise and inheritance view of the matching configurations:

Example:

Router# show running interface gigabitEthernet 0/0/0/30 
interface GigabitEthernet0/0/0/30 
! 
Router# show running inheritance interface GigabitEthernet 0/0/0/30 
interface GigabitEthernet0/0/0/30 ## Inherited from group l2tr 
mtu 1500  
 ## Inherited from group acref ipv4 
 access-group adem ingress 
 ## Inherited from group acref ipv4 
 access-group adem egress 
! 
Router# show running interface gigabitEthernet 0/0/0/31 
interface GigabitEthernet0/0/0/31 
! 
 Router# show running inheritance interface GigabitEthernet 0/0/0/31 
interface GigabitEthernet0/0/0/31 
## Inherited from group l2tr 
mtu 1500 
## Inherited from group acref ipv4 access-group adem ingress
## Inherited from group acref ipv4 access-group adem egress

Step 3

Check that the ACL group configuration actually got configured by using a traffic generator and watching that denied traffic is dropped.

ISIS Hierarchical Configuration

This example illustrates inheritance and priority handling with two ISIS groups using an ISIS configuration.

Procedure

Step 1

Configure the local ISIS configuration:

Example:

Router# show running router isis 
router isis vink 
net 49.0011.2222.2222.2222.00 
address-family ipv4 unicast 
 mpls traffic-eng level-1-2 
 mpls traffic-eng router-id Loopback0 redistribute connected 
! 

interface Bundle-Ether1 
 address-family ipv4 
 unicast 
! 

! 
interface Bundle-Ether2 
! 
interface Loopback0 
! 
interface TenGigE0/2/0/0.3521 
address-family ipv4 unicast 
 ! 
! 
interface TenGigE0/2/0/0.3522 
address-family ipv4 unicast 
 ! 
! 
interface TenGigE0/2/0/0.3523 
address-family ipv4 unicast 
 ! 
! 
interface TenGigE0/2/0/0.3524 
address-family ipv4 unicast 
 ! 
! 
interface TenGigE0/2/0/0.3525 
address-family ipv4 unicast 
 ! 
! 
interface TenGigE0/2/0/0.3526 
! 
interface TenGigE0/2/0/0.3527 
! 
interface TenGigE0/2/0/0.3528 
! 
interface TenGigE0/2/0/1 
address-family ipv4 unicast 
  ! 
 ! 
!

Step 2

Configure two ISIS groups and apply these to the configuration:

Example:

Router# show running group isis 
group isis router isis '.*' 
address-family ipv4 unicast mpls traffic-eng level-1-2 
 mpls traffic-eng router-id Loopback0 redistribute connected 
 redistribute ospf 1 level-1-2 
! 
interface 'TenGig.*' lsp-interval 40 
hello-interval 15 
address-family ipv4 unicast 
metric 50
 ! 
! 
interface 'Bundle-Ether.*' 
address-family ipv4 
unicast 
 metric 55 
  ! 
 ! 
! 
end-group 
Router# show running group isis2 

group isis2 router isis '.*' 
! 
router isis '^(vink)' address-family ipv4 unicast 
! 
interface '(^Ten)Gig.*' 
! 
interface '^(Ten)Gig.*' address-family ipv4 unicast 
metric 66 
 ! 
 ! 
! 
end-group 
Router# show running | inc apply-group 
Building configuration... 
apply-group isis l2tr isis2 mpp bundle1 acref

Step 3

Check the inheritance view of the ISIS configuration:

Example:

Router# show running inheritance router isis 
router isis vink 
net 49.0011.2222.2222.2222.00 
address-family ipv4 unicast 
mpls traffic-eng level-1-2 
mpls traffic-eng router-id Loopback0 redistribute connected 

## Inherited from group isis redistribute ospf 1 level-1-2 
! 
interface Bundle-Ether1 address-family ipv4 unicast 
## Inherited from group isis 
metric 55 
 ! 
! 
interface Bundle-Ether2 

## Inherited from group isis 
address-family ipv4 unicast 
## Inherited from group isis metric 55 
 ! 
! 
interface Loopback0 
! 
interface TenGigE0/2/0/0.3521 ## Inherited from group isis 
lsp-interval 40 
## Inherited from group isis 
hello-interval 15 
address-family ipv4 unicast 
## Inherited from group isis metric 50 
 ! 
! 
interface TenGigE0/2/0/0.3522 ## Inherited from group isis 
lsp-interval 40 
## Inherited from group isis hello-interval 15 
address-family ipv4 unicast ## Inherited from group isis 
metric 50 
 ! 
! 
interface TenGigE0/2/0/0.3523 ## Inherited from group isis 
lsp-interval 40 
## Inherited from group isis hello-interval 15 
address-family ipv4 unicast ## Inherited from group isis 
metric 50 
 ! 
! 
interface TenGigE0/2/0/0.3524 
## Inherited from group isis lsp-interval 40 
## Inherited from group isis hello-interval 15 
address-family ipv4 unicast 
## Inherited from group isis metric 50 
 ! 
! 
interface TenGigE0/2/0/0.3525 
 ## Inherited from group isis lsp-interval 40 
## Inherited from group isis hello-interval 15 
address-family ipv4 unicast
## Inherited from group isis metric 50 
 ! 
! 
interface TenGigE0/2/0/0.3526 
## Inherited from group isis lsp-interval 40 
## Inherited from group isis hello-interval 15 
## Inherited from group isis address-family ipv4 unicast 
## Inherited from group isis metric 50 
 ! 
! 
interface TenGigE0/2/0/0.3527 
## Inherited from group isis lsp-interval 40 
## Inherited from group isis hello-interval 15 
## Inherited from group isis address-family ipv4 unicast 
## Inherited from group isis metric 50 
 ! 
! 
interface TenGigE0/2/0/0.3528 
## Inherited from group isis lsp-interval 40 
## Inherited from group isis hello-interval 15 
## Inherited from group isis address-family ipv4 unicast 
## Inherited from group isis metric 50 
 ! 
! 

interface TenGigE0/2/0/1 

## Inherited from group isis lsp-interval 40 
## Inherited from group isis hello-interval 15 
address-family ipv4 unicast 
## Inherited from group isis metric 50 
  ! 
 ! 
!

Step 4

Verify the actual functionality.

Example:

Router# show isis interface TenGigE0/2/0/0.3528 | inc Metric 
Metric (L1/L2):	50/50

OSPF Hierarchy

This example illustrates hierarchical inheritance and priority. The configuration that is lower in hierarchy gets the highest priority.

Procedure

Step 1

Configure a local OSPF configuration:

Example:

Router# show running router ospf 
router ospf 1 
 apply-group go-c nsr 
router-id 121.121.121.121 nsf cisco 
redistribute connected address-family ipv4 unicast 
area 0 
 apply-group go-b 
interface GigabitEthernet0/0/0/0 
apply-group go-a 
! 
interface GigabitEthernet0/0/0/1 
! 
interface GigabitEthernet0/0/0/3 
! 
interface GigabitEthernet0/0/0/4 
! 
interface GigabitEthernet0/0/0/21 
 bfd minimum-interval 100 
 bfd fast-detect bfd multiplier 3 
! 
interface TenGigE0/2/0/0.3891 
! 
interface TenGigE0/2/0/0.3892 
! 
interface TenGigE0/2/0/0.3893 
! 

interface TenGigE0/2/0/0.3894 
  ! 
 ! 
! 
router ospf 100 
! 
router ospf 1000 
! 
router ospf 1001 
!

Step 2

Configure a configuration group and apply it in a configuration submode:

Example:

Router# show running group go-a 
group go-a router ospf '.*' 
area '.*' interface 'Gig.*' 
cost 200 
  ! 
 ! 
! 
end-group 
Router# show running group go-b 
group go-b router ospf '.*' 
area '.*' interface 'Gig.*' 
cost 250 
  ! 
 ! 
! 
end-group 
Router# show running group go-c 
group go-c router ospf '.*' 
area '.*' interface 'Gig.*' 
cost 300 
  ! 
 ! 
! 
end-group

Step 3

Check the inheritance view and verify that the apply-group in the lowest configuration submode gets the highest priority:

Example:

Router# show running inheritance router ospf 1 
router ospf 1 nsr 
router-id 121.121.121.121 nsf cisco 
redistribute connected address-family ipv4 unicast area 0 
interface GigabitEthernet0/0/0/0 ## Inherited from group go-a 
cost 200	<< apply-group in lowest submode gets highest priority 
! 
interface GigabitEthernet0/0/0/1 ## Inherited from group go-b 
cost 250 
! 
interface GigabitEthernet0/0/0/3 ## Inherited from group go-b 
cost 250 
! 
interface GigabitEthernet0/0/0/4 ## Inherited from group go-b 
cost 250 
! 
interface GigabitEthernet0/0/0/21 
bfd minimum-interval 100 
bfd fast-detect bfd multiplier 3 
## Inherited from group go-b 
cost 250 
! 
 interface TenGigE0/2/0/0.3891 
! 
interface TenGigE0/2/0/0.3892 
! 
interface TenGigE0/2/0/0.3893 
! 
interface TenGigE0/2/0/0.3894 
  ! 
 ! 
!

Step 4

Check the functionality of the cost inheritance through the group.

Example:

Router# show ospf 1 interface GigabitEthernet 0/0/0/0 
GigabitEthernet0/0/0/0 is up, line protocol is up 
 Internet Address 1.0.1.1/30, Area 0 
 Process ID 1, Router ID 121.121.121.121, Network Type BROADCAST, Cost: 200 
 Transmit Delay is 1 sec, State DR, Priority 1, MTU 1500, MaxPktSz 1500 
 Designated Router (ID) 121.121.121.121, Interface address 1.0.1.1 
 No backup designated router on this network 
 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 
 Non-Stop Forwarding (NSF) enabled 
 Hello due in 00:00:02 
Index 5/5, flood queue length 0 Next 0(0)/0(0) 
Last flood scan length is 1, maximum is 40 
Last flood scan time is 0 msec, maximum is 7 msec LS Ack List: current length 0, high water mark 0 Neighbor Count is 1, Adjacent neighbor count is 0 Suppress hello for 0 neighbor(s) 
Multi-area interface Count is 0

Replacing Configuration Elements

You can replace interface and IP address configurations, or any pattern in an existing configuration, using the replace {interface } or replace {pattern }commands in Global Configuration mode. These commands can be executed not only on individual interfaces or IP addresses, but also on regular expressions to replace a range of interfaces or addresses.

Use these commands to simplify configuration changes where you would normally need to copy the configuration and edit it manually. For example, when you’re moving a physical connection from one interface to another, you can use the replace interface command to update your configuration to use the new interface address.


Note

These commands replace every occurrence of the specified interfaces or patterns in the running configuration.

We recommend that you use this command after disconnecting the old interface and before connecting to the new interface.

Similarly, if your IP addressing scheme has changed (for example, a BGP neighbor address), use the replace pattern command to update your configuration to use the new IP address.

Configuration Example for Replacing an Interface Configuration

Procedure

The example in this section uses the following interface configurations:

Example:

Router# show configuration running-config 

interface MgmtEth0/RSP0/CPU0/0 shutdown 
! 
interface HundredGigE0/0/0/0 
 description first 
 ipv4 address 10.20.30.40 255.255.0.0 
 shutdown 
! 
interface HundredGigE0/0/0/1 
 shutdown 
! 
interface HundredGigE0/0/0/2description 10.20.30.40 
 shutdown 
! 
interface HundredGigE0/0/0/3 
 description 1020304050607080 
 shutdown 
! 
interface HundredGigE0/0/0/4

Configuration Example for Replacing IP Addresses in a Configuration

Procedure

Step 1

The example in this section uses the following configuration:

Example:

Router# show configuration running-config 

. . . 

ipv4 access-list mylist 

10 permit tcp 209.165.200.224/27 host 209.165.200.225 

20 deny ipv4 any 209.165.201.0/27 

! 

interface MgmtEth0/RSP0/CPU0/0 shutdown 

! 

interface HundredGigE0/1/0/1 description first 

ipv4 address 209.165.200.224/27 255.255.0.0 shutdown 

! 

interface HundredGigE0/0/0/2 description 209.165.200.224/27 shutdown 

! 

route-policy temp 

if ospf-area is 209.165.200.224/27 or source in (2.3.4.5/20) then pass 

endif end-policy 

!

Step 2

This example shows how to replace IP address 209.165.200.224/27 with 209.165.201.0/27 using the replace pattern 'pattern' with 'pattern' command:

Example:

Router(config)# replace pattern '209.165.200.224/27' with '209.165.201.0/27' 

Loading. 

443 bytes parsed in 1 sec (442)bytes/sec

Note

 

Use single quotes around the pattern.

Step 3

Enter the show configuration command to display and verify the configuration changes. Then commit the changes.

In the example below, you can see that every occurrence of IP address 209.165.200.224/27 is replaced with 209.165.201.0/27.

Example:

Router(config)# show configuration 

Building configuration... 

!! IOS XR Configuration 0.0.0 ipv4 access-list mylist 

no 10 

10 permit tcp 209.165.200.224/27 host 1.2.4.5 

! 

interface HundredGigE0/0/0/2 no description 

description 209.165.201.0/27 

! 

interface HundredGigE0/1/0/1 

no ipv4 address 209.165.200.224/27 255.255.0.0 

ipv4 address 209.165.201.0/27 255.255.0.0 

! 

! 

route-policy temp 

if ospf-area is 209.165.201.0/27 or source in (2.3.4.5/20) then pass 

endif end-policy 

! 

end 
Router(config)# commit

In the example above, you can see that every occurrence of IP address 209.165.200.224/27 has been replaced with 209.165.201.0/27.

Configuration Example for Replacing Patterns Using Regular Expressions

You can replace a range of interfaces or addresses using POSIX-compliant regular expressions.


Note

For information about using regular expressions, refer to the “Understanding Regular Expressions, SpecialCharacters, and Patterns” chapter in the Cisco ASR 9000 Series Aggregation Services Router Getting Started Guide.

Procedure

Step 1

The example in this section uses the following configuration:

Example:

Router# show configuration running-config 

. . . 

interface HundredGigE0/2/0/0 

ipv4 address 209.165.201.0/27 209.165.200.224/27 

! 

interface HundredGigE0/2/0/1 

ipv4 address 209.165.202.128/27 209.165.200.224/27 

! 

interface HundredGigE0/2/0/2 

ipv4 address 12.0.0.12 209.165.200.224/27 

! 

interface HundredGigE0/2/0/3 

ipv4 address 13.0.0.13 209.165.200.224/27 

! 

interface HundredGigE0/2/0/4 

ipv4 address 14.0.0.14 209.165.200.224/27 

! 

interface HundredGigE0/3/0/0 shutdown 

! 

interface HundredGigE0/3/0/1 shutdown 

! 

interface HundredGigE0/3/0/2 shutdown 

! 

interface HundredGigE0/3/0/3 shutdown 

! 

interface HundredGigE0/3/0/4 shutdown 

! 

interface HundredGigE0/3/0/5 shutdown 

! 

interface HundredGigE0/3/0/6 shutdown 

! 

end

Step 2

This example shows how to replace interfaces HundredGigE0/2/0/0 through HundredGigE0/2/0/4 with interfaces HundredGigE0/3/0/0 through HundredGigE0/3/0/4 using regular expressions:

Example:

Router(config)# replace pattern 'HundredGigE0/2/0/([0-4]*)' with 'HundredGigE0/3/0/1' 

Loading. 

619 bytes parsed in 1 sec (617)bytes/sec

Step 3

Enter the show configuration command to display and verify the configuration changes. Then commit the changes.

In this example, you can see that the HundredGigE0/2/0/x interfaces are removed from the configuration (no interface HundredGigE0/2/0/x) and is replaced with HundredGigE0/3/0/x.

Example:

Router(config)# show configuration 

Building configuration... 

!! IOS XR Configuration 0.0.0 no interface HundredGigE0/2/0/0 

 no interface HundredGigE0/2/0/1 no interface HundredGigE0/2/0/2 no interface HundredGigE0/2/0/3 no interface HundredGigE0/2/0/4 interface HundredGigE0/3/0/0 

ipv4 address 209.165.201.0/27 209.165.200.224/27 

! 

interface HundredGigE0/3/0/1 

ipv4 address 09.165.202.128/27 209.165.200.224/27 

! 

interface HundredGigE0/3/0/2 

ipv4 address 12.0.0.12 209.165.200.224/27 

! 

interface HundredGigE0/3/0/3 

ipv4 address 13.0.0.13 209.165.200.224/27 

! 

interface HundredGigE0/3/0/4 

ipv4 address 14.0.0.14 209.165.200.224/27 

! 

End 

 

Router(config)# commit