> Loopback Interface Configuration Mode Commands
> The Loopback Interface Configuration Mode is used to create and manage loopback interfaces that provide IP addresses that are always available and reachable from any interface within the same given context.
> Important: The commands or keywords/variables that are available are dependent on platform type, product version, and installed license(s).
> description
> Configures the description text for the current interface.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> description text
> no description
> no
> Clears the description for the interface.
> text
> Specifies the descriptive text to use. text must be 0 to 79 alpha and/or numeric characters with no spaces or a quoted string of printable characters
> Usage
> Set the description to provide useful information on the interface’s primary function, services, end users, etc. Any information useful may be provided.
> Example
> description sampleInterfaceDescriptiveText
> end
> Exits the interface configuration mode and returns to the Exec mode.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> end
> Usage
> Change the mode back to the Exec mode.
> exit
> Exits the interface configuration mode and returns to the context configuration mode.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> exit
> Usage
> Return to the context configuration mode.
> ip address
> Configures 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 specified IP address 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.
> ip_address ip_mask specifies an IP address and the subnet mask pair which is used to identify the IP address of the interface. ip_address must be specified using the standard IPv4 dotted decimal notation. Currently, the only value accepted for ip_mask is 255.255.255.255.
> ip_address/net_mask : the IP address and the length in bits of the network mask. This must be an IP address entered in dotted decimal notation and a mask (192.168.1.0/32). Currently, the only value accepted for bit_mask is 32.
> The secondary keyword is used to configure a secondary IP address on the interface. This is referred to as multi-homing of the interface.
> The srp-activate keyword activates the IP address for Interchassis Session Redundancy.
> 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
> This command configures the IP VPN Routing/Forwarding instance for the current interface.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> ip vrf forwarding vrf_name
> no vrf forwarding
> no
> Deletes the specified IP VPN routing/forwarding instance from the interface configuration.
> vrf_name
> Specifies the preconfigured IP VPN routing/forwarding instance name which is to be used with this interface.
> vrf_name must be a preconfigured VPN routing/forwarding instance name with 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
> Configures the IPv6 options for the current interface.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> ipv6address ipv6_address ip_mask [ srp-activate ]
> no iv6paddress 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 which is used to identify the IPv6 address of the interface. ipv6_address must be specified using the 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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