User Guide

OmniAccess SafeGuard OS Administration Guide
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Chapter 4: Configuring SafeGuard Controllers
Link Pair Synchronization
The SafeGuard Controller sits between the user and the network. It is important that if a
link between a user and the controller goes down, the link between the controller and the
network is also brought down. In addition, if the link between the controller and the
network goes down, the link between the user and the controller must be brought down.
This is required so that protocols can converge in the event of link failures. By default,
link pair synchronization is enabled on controllers.
Link pair synchronization is a feature available only on the SafeGuard Controller to
constantly monitor the link on both the user and network side. If either side of the link
fails or is brought down administratively, link pair synchronization will bring the other
side of the link down. Link pair synchronization will mark the link that it brought down
as SUSPENDED. If the failed link comes back up then link pair synchronization will
restore the link it brought down to UP state.
A link pair is a combination of neighbor ports, such as {P1,P2}, {P3, P4}, and so on. A link
pair cannot be formed with arbitrary port sets such as {P1, P5}. A link pair combination
consists of the user connected on one side of the pair and the network connected to the
other side of the pair.
The network administrator can monitor changes in link states using the
show port all
command.
For example:
(SafeGuard) #show port all
Admin Physical Physical Link LACP
Intf Type Mode Mode Status Status Mode
------ ------ ------- ---------- ---------- ------ -------
0/1 Enable Auto Down Disable short
0/2 Enable Auto Suspended Disable short
In the example above port 0/1 is down, so Link pari synchronization will suspend port
0/2 to allow for protocols such as STP, RSTP, EAP, etc to converge.
The current Link pair synchronization settings can be seen by executing the following
command from Privileged Exec mode:
(SafeGuard) #show linkpair-sync
Link pair synchronization is enabled.
(SafeGuard) #
To enable Link pair synchronization (enabled by default):
(SafeGuard) #config terminal
(SafeGuard) (config) #linkpair-sync enable
(SafeGuard) (config) #
To disable Link pair synchronization: