29.3.4 Operation when path switchback is suppressed and released

When the path switch-back suppression functionality is applied and a ring fault is detected on a master node, the master node status changes to recovery from restoration suppression, and the master node does not perform restoration operations immediately. To enable this functionality, the preempt-delay configuration command must be set.

The path switch-back suppression status is cleared when the following occur:

• Path switch-back suppression is cleared by executing the clear axrp preempt-delay operation command

• The path switch-back suppression time specified by the preempt-delay configuration command elapses

• The preempt-delay configuration command enabling path switch-back suppression functionality is deleted

When the recovery suppression state is released, the system performs recovery operations. When the restoration is completed, the master node switches to the fault monitoring status.

If a ring failure occurs while path switchback is suppressed, the master node changes to the recovery monitoring state again.

The figure below shows the operations performed when the clear axrp preempt-delay operation command is executed to clear path switch-back suppression. The same operation is performed when this status is cleared by other means.

Figure 29-12: Operation when path switchback suppression is released by executing an operation command

The switch-back suppression status is also cleared for paths, and the master node status changes to fault monitoring status when the following events occur:

• A device starts up (including by execution of the reload and ppupdate operation commands).

• Reflecting to configuration file operation (executing the copy operation command)

• A Ring Protocol program is restarted (including by execution of the restart axrp operation command).

• A VLAN program is restarted (including by execution of the restart vlan operation command).