> 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.
> Important: The commands or keywords/variables that are available are dependent on platform type, product version, and installed license(s).
> crypto-map
> Applies the specified IPSec crypto-map to this interface.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> crypto-map map_name [ secondary-address sec_ip_addr ]
> no
> Deletes the application of the crypto map on this interface.
> map_name
> Specifies the name of the crypto map being applied. The name is an alphanumeric string of 1 through 127 characters that is case sensitive.
> secondary-address sec_ip_addr
> Applies the crypto map to the secondary address for this interface that is specified by sec_ip_addr. sec_ip_addr must be specified using the IPv4 dotted-decimal or IPv6 colon-separated notation.
> Usage
> In order for ISAKMP and/or manual crypto maps to work, they must be applied to a specific interface using this command. Dynamic crypto maps should not be applied to interfaces.
> The crypto map must be configured in the same context as the interface.
> Example
> To apply the IPSec crypto map named cmap1 to this interface, use the following command:
> crypto-map cmap1
> description
> Use this command to configure the descriptive 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. For text, enter an alphanumeric string of 0 through 79 characters. If spaces or special characters are required, the stirng must be bracketed with double quotation marks.
> Usage
> Set the description to provide any useful information on the interface’s primary function, services, end users.
> Example
> description sampleInterfaceDescriptiveText
> end
> Exits the current configuration mode and returns to the Exec mode.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> end
> Usage
> Use this command to return to the Exec mode.
> exit
> Exits the current mode and returns to the parent configuration mode.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> exit
> Usage
> Use this command to return to the parent 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. ip_address is entered in IPv4 dotted-decimal or IPv6 colon-separated notation. Currently, the only value accepted for ip_mask is 255.255.255.255 (IPv4) or 120 (IPv6) .
> For the network mask, ip_address/net_mask, enter the IP address and the length in bits of the network mask, Fo example, 192.168.1.0/32 (IPv4) or fe80::c0a8:100/32 (IPV6). 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 10.2.3.4
> ip vrf
> Use this command to configure the IP VPN Routing Forwarding (VRF) instance for the current interface.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> ip vrf forwarding vrf_name no vrf forwarding
> no
> Deletes the IP VRF instance you specify from the interface configuration.
> vrf_name
> Specifies the preconfigured IP VRF instance name to be used with this interface.
> For vrf_name, enter a VRF instance name that was preconfigured via the ip vrf forwarding command in Context Configuration mode.
> Usage
> Use this command to associate a preconfigured IP VRF instance for the current interface.
> Example
> The following command associates a preconfigured IP VRF 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 IPv6 colon-separated 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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