enable isis area adjacency-check

enable isis area area_name adjacency-check {ipv4 | ipv6}

Description

This command enables the checking of the following TLVs when forming adjacencies: Protocols Supported and IP Interface Address.

Syntax Description

area_name Specifies the name of the IS-IS router process that should perform the adjacency check.
ipv4 Specifies that the adjacency check is to be performed in IPv4 interfaces.
ipv6 Specifies that the adjacency check is to be performed in IPv6 interfaces.

Default

ipv4/ipv6: Enabled.

Usage Guidelines

When enabled for IPv4, IPv4 adjacencies may only be formed with neighbors whose connected interface supports IPv4 and is on the same subnet as the receiving interface. Similarly, when enabled for IPv6, IPv6 adjacencies may only be formed with neighbors whose connected interface supports IPv6 and is on the same link local subnet as the receiving interface. For each enabled protocol, if both criteria are not met, received Hello PDUs are discarded. By default, IPv4 routing is affected by this command. The optional ipv6 keyword enables adjacency checking for IPv6 interfaces on the specified router process. It may be necessary to disable adjacency checking in multi-topology environments where a neighbor may only form an IPv4 or an IPv6 adjacency, but not both.

Example

The following command directs the IS-IS process named areax to perform adjacency checks on IPv6 interfaces:

enable isis area areax adjacency-check ipv6

History

This command was first available in ExtremeXOS 12.1.

Platform Availability

This command is available on platforms with a Premier license as described in the Switch Engine v33.1.1 Licensing Guide document.