IS-IS CLI levels

The CLI includes various levels of commands for IS-IS. The figure below shows these levels, including the levels used for IPv6 IS-IS.

IPv6 IS-IS CLI levels

The IPv6 IS-IS CLI levels are as follows:

• A global level for the configuration of the IS-IS protocol. At this level, all IS-IS configurations at this level apply to IPv4 and IPv6. Enter this layer using the router isis command.
  • Under the global level, you specify an address family. Address families separate the IS-IS configuration IPv6 and IPv4. You enter this level by entering the address-family command at the router IS-IS level.
  • Under the address family level, you select a sub-address family, which is the type of routes for the configuration. For IS-IS, you specify unicast.
  • An interface level.

The implementation of IPv6 IS-IS includes a new configuration level: ISIS address-family IPv6 unicast configuration mode. You enter IS-IS definitions for IPv6 IS-IS under this level. Address-family allows you to create configurations for IPv6 IS-IS unicast routes that are separate and distinct from configurations for IPv4 IS-IS unicast routes.

Note

Each address family configuration level allows you to access commands that apply to that particular address family only. To enable a feature in a particular address family, you must specify any associated commands for that feature in that particular address family. A feature configured in IS-IS IPv4 unicast address family configuration mode does not work for the IPv6 IS-IS unicast address family unless it is explicitly configured in ISIS address-family IPv6 unicast configuration mode. .