Preempt mode

When preempt mode is enabled (the default setting), a higher priority backup router can preempt a lower priority primary router. This can happen if the primary router fails, the backup router becomes the primary router, and the failed primary router restarts. Since the restarted router has a higher priority, if preempt mode is enabled, the restarted router replaces the current primary router becoming the new primary router. If preempt mode is disabled, a restarted router that has a higher priority would not take over as the primary router.

To configure preempt mode in IPv4 VRRP:

config system interface
    edit <name>
        config vrrp
            edit <vrid>
                set preempt {enable | disable}
            next
        end
    next
end

To configure preempt mode in IPv6 VRRP:

config system interface
    edit <name>
        config ipv6
            config vrrp6
                edit <vrid>
                    set preempt {enable | disable}
                next
            end
        end
    next
end