CLI Guide

within hellos. The router with the highest priority becomes the designated
intermediate system (DIS).
NOTE: Routers with a priority of 0 cannot be a designated router.
Setting the priority to 0 lowers the chance of this system becoming the DIS, but
does not prevent it. If all the routers have priority 0, one with highest MAC address
becomes DIS even though its priority is 0.
is-type
Configure IS-IS operating level for a router.
Syntax
is-type {level-1 | level-1-2 | level-2-only}
To return to the default values, use the no is-type command.
Parameters
level-1 Allows a router to act as a Level 1 router.
level-1-2 Allows a router to act as both a Level 1 and Level 2 router.
This setting is the default.
level-2-only Allows a router to act as a Level 2 router.
Defaults level-1-2
Command Modes ROUTER ISIS
Supported Modes Full–Switch
Command History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage Information
The IS-IS protocol automatically determines area boundaries and are able to keep
Level 1 and Level 2 routing separate. Poorly planned use of this feature may cause
configuration errors, such as accidental area partitioning.
If you are configuring only one area in your network, you do not need to run both
Level 1 and Level 2 routing algorithms. You can configure the IS type as Level 1.
912
Intermediate System to Intermediate System (IS-IS)