IPv6 Management Features

Viewing and Clearing the IPv6 Neighbors Cache

Clearing the Neighbor Cache

When there is an event such as a topology change or an address change, the neighbor cache may have too many entries to allow efficient use. Also, if an unauthorized client is answering DAD or normal neighbor solicitations with invalid replies, the neighbor cache may contain a large number of invalid entries and communication with some valid hosts may fail and/or the show ipv6 neighbors command output may become too cluttered to efficiently read. In such cases, the fastest way to restore optimum traffic movement on a VLAN may be to statically clear the neighbor table instead of waiting for the unwanted entries to time-out.

Syntax: clear ipv6 neighbors

Executed at the global config level, this command removes all non-local IPv6 neighbor addresses and corresponding MAC addresses from the neighbor cache. (Local IPv6 addresses, that is, IPv6 addresses configured on the VLAN interface for the switch on which the command is executed, are not removed.) Removed addresses are listed in the command output.

ProCurve(config)# clear ipv6 neighbors

2001:db8:260:212::1%vlan10 deleted fe80:::10:27%vlan10 deleted fe80::213:c4ff:fedd:14b0%vlan10 deleted

Figure 5-3. Example of Clearing the IPv6 Neighbors Cache

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