Accton Technology 24/48-Port, ES4548D, ES4524D manual Current Neighbor Cache Table

5 Setting an IP Address

-Configuring a value of 0 disables duplicate address detection.

-Duplicate address detection determines if a new unicast IPv6 address already exists on the network before it is assigned to an interface.

-Duplicate address detection is stopped on any interface that has been suspended (see “Creating VLANs” on page 23-6). While an interface is suspended, all unicast IPv6 addresses assigned to that interface are placed in a “pending” state. Duplicate address detection is automatically restarted when the interface is administratively re-activated.

-An interface that is re-activated restarts duplicate address detection for all unicast IPv6 addresses on the interface. While duplicate address detection is performed on the interface’s link-local address, the other IPv6 addresses remain in a “tentative” state. If no duplicate link-local address is found, duplicate address detection is started for the remaining IPv6 addresses.

-If a duplicate address is detected, it is set to “duplicate” state, and a warning message is sent to the console. If a duplicate link-local address is detected, IPv6 processes are disabled on the interface. If a duplicate global unicast address is detected, it is not used. All configuration commands associated with a duplicate address remain configured while the address is in “duplicate” state.

-If the link-local address for an interface is changed, duplicate address detection is performed on the new link-local address, but not for any of the IPv6 global unicast addresses already associated with the interface.

Current Neighbor Cache Table

•IPv6 Address – IPv6 address of neighbor device.

•Age – The time since the address was verified as reachable (in minutes). A static entry is indicated by the value “Permanent.”

•Link-layer Address – Physical layer MAC address.

•State – The current state for an entry.

The following states are used for dynamic entries:

-INCMP (Incomplete) - Address resolution is being carried out on the entry.

A neighbor solicitation message has been sent to the multicast address of the target, but it has not yet returned a neighbor advertisement message.

-REACH (Reachable) - Positive confirmation was received within the last ReachableTime interval that the forward path to the neighbor was functioning. While in REACH state, the device takes no special action when sending packets.

-STALE - More than the ReachableTime interval has elapsed since the last positive confirmation was received that the forward path was functioning. While in STALE state, the device takes no action until a packet is sent.

-DELAY - More than the ReachableTime interval has elapsed since the last positive confirmation was received that the forward path was functioning. A packet was sent within the last DELAY_FIRST_PROBE_TIME interval. If no reachability confirmation is received within this interval after entering the DELAY state, the switch will send a neighbor solicitation message and change the state to PROBE.

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