> # Tracking the Interface Priority

> Interface state tracking changes the priority of the virtual router based on the state of another interface in the switch. When the tracked interface is down, the priority reverts to the priority value for the virtual router (see the "Setting Virtual Router Authentication" topic). When the tracked interface is up, the priority of the virtual router is restored to the interface state tracking value. You can track the state of either a specified VSAN interface or the management interface (mgmt 0). The interface state tracking feature is disabled by default.

> Note For interface state tracking to function, you must enable preemption on the interface.

> Copyright 2010-2015, Cisco Systems, Inc. All rights reserved.