C613-50102-01 REV C
Command Reference for x510 Series
1949
AlliedWare Plus™ Operating System - Version 5.4.6-1.x
V
IRTUAL
C
HASSIS
S
TACKING
(VCS
TACK
™) C
OMMANDS
MAC
ADDRESS
-
TABLE
VCS
-
SYNC
-
MODE
mac address-table vcs-sync-mode
Overview
Use this command to allow a MAC address learnt on one stack member to be used
on any other stack member. Note that this command is only necessary in unusual
circumstances, as described in the Usage section below.
Syntax
mac address-table vcs-sync-mode
no mac address-table vcs-sync-mode
Default
Disabled
Mode
Global configuration
Usage
MAC addresses are automatically learnt by stack members when a packet is seen
by that stack member. Normally this is sufficient to make sure that all stack
members that need the MAC address learn it.
If aggregators are used, it is possible for the path taken by packets travelling from
host A to B to traverse different stack members than packets travelling from host B
to A. In this case, the MAC addresses may not be learnt and traffic could be flooded.
Even in this case, a broadcast packet from each unit, such as an ARP packet, would
be enough to cause all stack members to learn these MAC addresses.
However, in very unusual cases, the automatic learning can still lead to some
flooding. This command resolves such situations by synchronising MAC address
entries between stack members. This will prevent the flooding that would
otherwise occur in these unusual cases.
Note that enabling this feature has a small impact on CPU performance, because it
slightly increases the numbers of packets sent to the CPU.
Example
To make a MAC address learned by one stack member available to all members in
the stack, use the commands:
awplus#
configure terminal
awplus(config)#
mac address-table vcs-sync-mode
Related
Commands
