US 12,088,494 B2
Leveraging a hybrid usage of software and hardware to support a multi-tiered nexthop failover to backup nexthop handling
Tim Tang, Burnaby (CA); and Mayukh Saubhasik, Richmond (CA)
Assigned to Arista Networks, Inc., Santa Clara, CA (US)
Filed by Arista Networks, Inc., Santa Clara, CA (US)
Filed on Aug. 10, 2021, as Appl. No. 17/398,308.
Claims priority of provisional application 63/066,118, filed on Aug. 14, 2020.
Prior Publication US 2022/0052941 A1, Feb. 17, 2022
Int. Cl. H04L 12/707 (2013.01); H04L 43/0811 (2022.01); H04L 45/00 (2022.01)
CPC H04L 45/22 (2013.01) [H04L 43/0811 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A network device for forwarding packets in a network comprising an adjacent device connected to the network device via a link, comprising:
a switching system for directing the packets between ports of the network device, wherein a port of the ports is operably connected to the adjacent device via the link; and
a switching system manager programmed to:
identify a failure of the link;
in response to identifying the failure of the link, update link state information stored in forwarding hardware of the switching system based on the failure of the link to obtain updated link state information;
process a packet using a backup next hop in a next hop backup protected entry, wherein the next hop backup protected entry comprises a primary next hop and the backup next hop, wherein the primary next hop is associated with the link, wherein the backup next hop is selected over the primary next hop based on the updated link state information;
update, using a pre-computed next hop, the primary next hop in the next hop backup protected entry to obtain an updated next hop backup protected entry, wherein the pre-computed next hop was determined prior to the failure of the link; and
update the updated next hop backup protected entry using current network state information of the network, to obtain a second updated next hop backup protected entry, wherein the current network state information specifies the failure of the link.