show ipv6 neighbors
Syntax
show ipv6 neighbors [vlan vid]
Description
Displays IPv6 neighbor information currently held in the neighbor cache. After a period without communication with a given neighbor, the switch drops that neighbor's data from the cache. The command lists neighbors for all VLAN interfaces on the switch or for only the specified VLAN. The following fields are included for each entry in the cache:
Options
- IPv6 Address
Lists the 128-bit addresses for the local host and any neighbors (on the same VLAN) with whom there has been recent communication.
- MAC address
The MAC address corresponding to each of the listed IPv6 addresses.
- VLAN vid
Optional. Causes the switch to list only the IPv6 neighbors on a specific VLAN configured on the switch.
- Type
Appears only when VLAN is not specified and indicates whether the corresponding address is local (configured on the switch) or dynamic (configured on a neighbor device.
- Age
Appears only when the VLAN is specified and indicates the length of time the entry has remained unused.
- Port
Identifies the switch port on which the entry was learned. If this field is empty for a given address, the address is configured on the switch itself.
- State
- A neighbor destination is reachable from a given source address if confirmation has been received at the source verifying that traffic has been received at the destination. This field shows the reachability status of each listed address:
- INCMP
(Incomplete): Neighbor address resolution is in progress, but has not yet been determined.
- REACH
(Reachable): The neighbor is known to have been reachable recently.
- STALE
A timeout has occurred for reachability of the neighbor, and an unsolicited discovery packet has been received from the neighbor address. If the path to the neighbor is then used successfully, this state is restored to REACH.
- DELAY
Indicates waiting for a response to traffic sent recently to the neighbor address. The time for determining the neighbor's reachability has been extended.
- PROBE
The neighbor might not be reachable. Periodic, unicast neighbor solicitations are being sent to verify reachability.
Example output
Neighbor cache without specifying a VLAN
Switch(config)# show ipv6 neighbor
IPv6 ND Cache Entries
IPv6 Address MAC Address State Type Port
--------------------------- ------------- ----- ------- ----
2001:db8:260:212::101 0013c4-dd14b0 STALE dynamic 1
2001:db8:260:214::1:15 001279-88a100 REACH local
fe80::1:1 001279-88a100 REACH local
fe80::10:27 001560-7aadc0 REACH dynamic 3
fe80::213:c4ff:fedd:14b0 0013c4-dd14b0 REACH dynamic 1