track interface

Use this command to configure tracking of the interface for the device within a VRRPv3 group. Use the bfdneighbor option to track the reachability to the uplink next hop address. Once interface tracking is configured, the VRRPv3 feature receives notifications when the interface changes state. If BFD tracking is enabled with bfdneighbor config, then a BFD session is created with the BFD destination IP as that of the given BFD neighbor IP address, VRRPv3 receives notification when the BFD session state changes. The decrement option can be set to decrease the priority of the device within a VRRPv3 group by the specified value when the interface goes down, or the associated BFD session goes down. Similarly, the priority is increased by the same specified value when the interface comes up or the associated BFD session comes up. If the decrement value is not set, then the default decrement value used is 10. The overall state of a track interface object is considered as up only when both of the events (interface up event and BFD session up event) are received. The decrement or increment of priority is done based on the overall state of the track interface object.