Configuring the IS-IS IPv4 unicast address family

1. Enter the configure terminal command to access global configuration mode.
   

   device# configure terminal

2. Enter the router isis command to enter IS-IS router configuration mode and enable IS-IS on the device.
   

   device(config)# router isis
   

3. Enter the address-family ipv4 unicast command to enable ISIS address-family IPv4 unicast configuration mode.
   

   device(config-isis-router)# address-family ipv4 unicast
   

Example

The following example enables ISIS address-family IPv4 unicast configuration mode.

device# configure terminal
device(config)# router isis
device(config-isis-router)# address-family ipv4 unicast
device(config-router-isis-ipv4u)#