Loopback Interface Configuration Mode Commands

Loopback Interface Configuration Mode Commands
 
 
Use the Loopback Interface Configuration mode to create and manage loopback interfaces that provide IP addresses that are always available and reachable from any interface within a given context.
 
note_smallImportant: The commands or keywords/variables that are available are dependent on platform type, product version, and installed license(s).
 
description
Use this command to configure the descriptive text for the current interface.
Product
All
Privilege
Security Administrator, Administrator
Syntax
description textno description
no
Clears the description for the interface.
text
Specifies the descriptive text to use. Fortext, enter 0 to 79 alpha and/or numeric characters with no spaces, or a string of printable characters within quotes.
Usage
Set the description to provide any useful information on the interface’s primary function, services, end users.
Example
description sampleInterfaceDescriptiveText
 
end
Enter this command to exit the interface configuration mode and return to the Exec mode.
Product
All
Privilege
Security Administrator, Administrator
Syntax
end
Usage
Change the mode back to the Exec mode.
 
exit
Enter this command to exit the interface configuration mode and return to the context configuration mode.
Product
All
Privilege
Security Administrator, Administrator
Syntax
exit
Usage
Return to the context configuration mode.
 
ip address
Use this command to configure the IP options for the current interface.
Product
All
Privilege
Security Administrator, Administrator
Syntax
ip address { ip_address ip_mask | ip_address/bitmask } [ secondary | srp-activate ]
no ip address ip_address
no
Deletes the IP address you specify from the interface configuration.
address {ip_address ip_mask | ip_address/bitmask} [ secondary | srp-activate ]
Configures the IP address and network mask for the interface.
Enter an ip_address ip_mask to specify an IP address and the subnet mask pair that identifies the IP address of the interface. For ip_address, specify with standard IPv4 dotted decimal notation. Currently, the only value accepted for ip_mask is 255.255.255.255.
For the network mask, ip_address/net_mask, enter the IP address and the length in bits of the network mask in dotted decimal notation and a mask (192.168.1.0/32). Currently, the only value accepted for bit_mask is 32.
Use the secondary keyword ito configure a secondary IP address on the interface. This is referred to as multi-homing of the interface.
Use the srp-activate keyword to activate the IP address for Interchassis Session Recovery (ICSR).
Usage
Create and manage loopback interfaces for the current context.
Example
The following command configures IP address to associate with the interface:
ip address 1.2.3.4 255.255.255.255
The following command removes the associated IP address for the interface:
no ip address 1.2.3.4
 
ip vrf
Use this command to configure the IP VPN routing/forwarding instance for the current interface.
Product
All
Privilege
Security Administrator, Administrator
Syntax
ip vrf forwarding vrf_nameno vrf forwarding
no
Deletes the IP VPN routing/forwarding instance you specify from the interface configuration.
vrf_name
Specifies the preconfigured IP VPN routing/forwarding instance name to be used with this interface.
For vrf_name, enter a preconfigured VPN routing/forwarding instance name with the ip vrf forwarding command in Context Configuration mode.
Usage
Use this command to associate a preconfigured IP VPN routing/forwarding instance for the current interface.
Example
The following command associates a preconfigured IP routing/forwarding instance named vrf_1 with this interface:
ip vrf forwarding vrf_1
 
ipv6 address
Use this command to configure the IPv6 options for the current interface.
Product
All
Privilege
Security Administrator, Administrator
Syntax
ipv6 address ipv6_address ip_mask [ srp-activate ]
no iv6p address ipv6_address
no
Deletes the specified IPv6 address from the interface configuration.
address ipv6_address ip_mask [ srp-activate ]
Configures the IP address and network mask for the interface.
ipv6_address ip_mask specifies an IP address and the subnet mask pair that identifies the IPv6 address of the interface. Specify ipv6_address in standard IPv6 dotted decimal notation.
The srp-activate keyword activates the IPv6 address for Session Recovery.
Usage
Create and manage loopback interfaces for the current context and enable Session Redundancy Protocol (SRP) when appropriate.
Example
The following command configures an IPv6 address to associate with the interface and enables SRP:
ipv6 address 2001:268:2008:b::1021/128 srp-activate
 
 
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