Concept Guide

level-2 (OPTIONAL) Specify the priority for Level 2.
Defaults value = 64; level-1 (if not otherwise specied).
Command Modes INTERFACE
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
You can congure priorities independently for Level 1 and Level 2. Priorities determine which router on a LAN is the
designated router. Priorities are advertised 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
Congure 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 conguration errors, such as accidental area partitioning.
If you are conguring only one area in your network, you do not need to run both Level 1 and Level 2 routing
algorithms. You can congure the IS type as Level 1.
Intermediate System to Intermediate System (IS-IS) 791