Configuring the neighbor cache

Configure the address translation table used to map IPv6 addresses to physical addresses. You can manually add static neighbors to the cache.

Note

Note

IPv6 static neighbors are not supported on SMLT.

About this task

Neighbor cache in IPv6 is similar to the IPv4 Address Resolution Protocol (ARP) table.

The neighbor cache is a set of entries for individual neighbors to which traffic was recently sent.

You make entries on the neighbor on-link unicast IP address, including information such as the link-layer address.

A neighbor cache entry contains information used by the Neighbor Unreachability Detection algorithm, including the reachability state, the number of unanswered probes, and the time the next Neighbor Unreachability Detection event is scheduled.

Procedure

  1. Enter Global Configuration mode:

    enable

    configure terminal

  2. Create a static neighbor:

    ipv6 neighbor WORD<0-128> port {slot/port[sub-port]} mac <0x00:0x00:0x00:0x00:0x00:0x00> [vlan <1-4059> ]

    When you create a static neighbor, it always remains in the reachable state. This differs from the general neighbor cache behavior where, among other things, timers and neighbor unreachability detection events can be generated.

Example

Create a static neighbor:

Switch:1(config)#ipv6 neighbor 3000::3 port 1/11 mac 00-1A-4B-8A-FB-6B

Variable definitions

Use the data in the following table to use the ipv6 neighbor command.

Variable

Value

mac <0x00:0x00:0x00:0x00:0x00:0x00>

Specifies the MAC address.

{slot/port[/sub-port]}

Identifies a single slot and port. If the platform supports channelization and the port is channelized, you must also specify the sub-port in the format slot/port/sub-port.

vlan <1-4059>

Specifies the VLAN ID in the range of 1 to 4059. By default, VLAN IDs 1 to 4059 are configurable and the system reserves VLAN IDs 4060 to 4094 for internal use. On switches that support the vrf-scaling and spbm-config-mode boot configuration flags, if you enable these flags, the system also reserves VLAN IDs 3500 to 3998. VLAN ID 1 is the default VLAN and you cannot create or delete VLAN ID 1.

WORD<0-128>

Specifies the IPv6 address in hexadecimal colon format.