adjacency-strict-check enable

Usage Scenario

During the establishment of IS-IS neighbor relationships, if both IPv4 and IPv6 are configured at both ends, both IPv4 and IPv6 neighbors are established. By default, IPv4 and IPv6 share the standard topology. When the faulty link is restored, IPv4 goes Up faster than IPv6. After the IS-IS router receives a message indicating that IPv4 goes Up, it considers that both IPv4 and IPv6 neighbors are established. If IPv6 packets are being transmitted at that time, some of these IPv6 packets are discarded.

To resolve this problem, run the adjacency-strict-check enable command to enable IS-IS adjacency strict-check to ensure that an IS-IS neighbor is established only when both IPv4 and IPv6 go Up.

Prerequisites

You have created an IS-IS process and entered the IS-IS view using the isis command.

Configuration Impact

After you run the adjacency-strict-check enable command on a broadcast network, the basic topology becomes Down if the IP protocol enabled on the local router is different from that on its neighbors.

After you run the adjacency-strict-check enable command on a P2P network, neighbor relationships cannot be established if the IP protocol enabled on the local router is different from that on its neighbors and only the basic topology is available for the local router.

Precautions

undo adjacency-strict-check [ enable ] and undo adjacency-strict-check commands have the same function, enable is just provide convenience for users.