Fast convergence in VRRP with multipoint bidirectional forwarding detection

A first network device to enable detection of a failure of a network device acting as a master of a virtual router redundancy protocol (VRRP) group of network devices, the first network device comprising:

• a non-transitory machine-readable storage medium configured to store a VRRP multipoint bidirectional forwarding detection (BFD) module;
• and
• a network processor communicatively coupled to the non-transitory machine-readable storage medium, the network processor operative to execute the VRRP multipoint BFD module, the VRRP multipoint BFD module operative to,
• determine whether a first priority associated with the first network device is a highest priority when it is compared with priorities respectively associated with other network devices of the VRRP group,
• responsive to determining that the first priority associated with the first network device is the highest priority, the VRRP multipoint BFD module is further operative to,
• cause the first network device to assume a master role in the VRRP group, and
• establish a multipoint bidirectional forwarding detection (BFD) head session, wherein the multipoint BFD head session indicates that the first network device is acting as a head of a multipoint BFD tree, and the other network devices of the VRRP group act as tails of the multipoint BFD tree;
• responsive to determining that the first priority associated with the first network device is not the highest priority, the VRRP multipoint BFD module is further operative to:
• cause the first network device to assume a backup role in the VRRP group, and
• establish a multipoint BFD tail session, wherein the multipoint BFD tail session indicates that the first network device is configured to act as a tail of the multipoint BFD tree,
• listen to BFD control packets to be received from a second network device, wherein the second network device acts as a head of the multipoint BFD tree and further assumes a master role in the VRRP group,
• detect a failure of the multipoint BFD tail session, wherein the failure of the multipoint BFD tail session is indicative of the failure of the second network device which assumes the master role in the VRRP group;
• and
• responsive to detecting the failure of the multipoint BFD tail session, initiate a change of state of the VRRP group based on priorities associated with the network devices from the VRRP group, and wherein the change of state includes the determination of an identity of a new master network device for the VRRP group different from the second network device.

A non-transitory computer-readable storage medium having computer code stored therein, which when executed by a processor of a first network device for enabling detection of a failure of a network device acting as a master of a virtual router redundancy protocol (VRRP) group of network devices, cause the first network device to perform operations comprising:

• determining whether a first priority associated with the first network device from the VRRP group is a highest priority when it is compared with priorities respectively associated with other network devices from the VRRP group;
• and
• responsive to determining that the first priority associated with the first network device is the highest priority, performing the following:
• causing the first network device to assume a master role in the VRRP group, and
• establishing a multipoint bidirectional forwarding detection (BFD) head session, wherein the multipoint BFD head session indicates that the first network device is acting as a head of a multipoint BFD tree, and the other network devices of the VRRP group act as tails of the multipoint BFD tree;
• responsive to determining that the first priority associated with the first network device is not the highest priority, performing the following:
• causing the first network device to assume a backup role in the VRRP group, and
• establishing a multipoint BFD tail session, wherein the multipoint BFD tail session indicates that the first network device is configured to act as a tail of the multipoint BFD tree,
• listening to BFD control packets to be received from a second network device, wherein the second network device acts as a head of the multipoint BFD tree and further assumes a master role in the VRRP group,
• detecting a failure of the multipoint BFD tail session, wherein the failure of the multipoint BFD tail session is indicative of the failure of the second network device which assumes the master role in the VRRP group;
• and
• responsive to detecting the failure of the multipoint BFD tail session, initiating a change of state of the VRRP group based on priorities associated with the network devices from the VRRP group, and wherein the change of state includes the determination of an identity of a new master network device for the VRRP group different from the second network device.