Configuring IS-IS Route Summarization

Before configuring IS-IS route summarization, configure basic IS-IS functions.

Run system-view

The system view is displayed.
Run isis [ process-id ]

The IS-IS view is displayed.
Run summary ip-address mask [ avoid-feedback | generate_null0_route | tag tag | [ level-1 | level-1-2 | level-2 ] ] ^*

The specified IS-IS routes are summarized into one IS-IS route.

After route summarization is configured on a device, the local routing table still contains all specific routes before the summarization. The routing tables on other devices contain only the summary route, and the summary route is deleted only after all its specific routes are deleted.

Run the display isis route command to check summary routes in the IS-IS routing table.
Run the display ip routing-table [ verbose ] command to check summary routes in the IP routing table.