Configuring the Asymmetric Hold Time for VRRP Routers

In Junos OS Release 9.5 and later, the asymmetric-hold-time statement at the [edit protocols vrrp] hierarchy level enables you to configure a VRRP primary router to switch over to the backup router immediately—that is, without waiting for the priority hold time to expire—when a tracked interface or route goes down or when the bandwidth of a tracked interface decreases. Such events can cause an immediate reduction in the priority based on the configured priority cost for the event, and trigger a primary-role election.

However, when the tracked route or interface comes up again, or when the bandwidth for a tracked interface increases, the backup (original primary) router waits for the hold time to expire before it updates the priority and initiates the switchover if the priority is higher than the priority for the VRRP primary (original backup) router.

If the asymmetric-hold-time statement is not configured, the VRRP primary waits for the hold time to expire before it initiates a switchover when a tracked route goes down or when the bandwidth of a tracked interface decreases.

Example: Configuring Asymmetric Hold Time