Configuring authentication

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 auth-mode command with the md5 and level-1 parameters to configure MD5 authentication for Level 1 packets.
   

   device(config-isis-router)# auth-mode MD5 level-1
   

4. Enter the auth-check disable command with the level-1 parameter to temporarily disable authentication checking globally for Level 1 packets.
   

   device(config-isis-router)# auth-check level-1 disable
   

5. Enter the auth-key command with the level-1 parameters, specifying an authentication password to configure an authentication key globally for Level 1 packets.
   

   device(config-isis-router)# auth-key level-1 mysecurekey
   

   

   Note

   MD5 passwords cannot have ASCII character 32 ('SPACE') as a part of the password string.

The following example configures IS-IS authentication mode, an IS-IS authentication key and temporarily disables IS-IS authentication checking for Level 1 packets.

device# configure terminal
device(config)# router isis
device(config-isis-router)# auth-mode MD5 level-1
device(config-isis-router)# auth-check level-1 disable
device(config-isis-router)# auth-key level-1 mysecurekey