neighbor 192.168.10.1 remote-as 65123neighbor 192.168.10.1 update-source Loopback 0neighbor 192.168.10.1 no shutdownneighbor 192.168.12.2 remote-as 65123neighbor 192.168.12.2 allowas-in 9neighbor 192.168.12.2 update-source Loopback 0neighbor 192.168.12.2 no shutdownR2(conf-router_bgp)#R2(conf-router_bgp)#Enabling Graceful RestartUse this feature to lessen the negative effects of a BGP restart.Dell Networking OS advertises support for this feature to BGP neighbors through a capabilityadvertisement. You can enable graceful restart by router and/or by peer or peer group.NOTE: By default, BGP graceful restart is disabled.The default role for BGP is as a receiving or restarting peer. If you enable BGP, when a peer that supportsgraceful restart resumes operating, Dell Networking OS performs the following tasks:• Continues saving routes received from the peer if the peer advertised it had graceful restart capability.Continues forwarding traffic to the peer.• Flags routes from the peer as Stale and sets a timer to delete them if the peer does not perform agraceful restart.• Deletes all routes from the peer if forwarding state information is not saved.• Speeds convergence by advertising a special update packet known as an end-of-RIB marker. Thismarker indicates the peer has been updated with all routes in the local RIB.If you configure your system to do so, Dell Networking OS can perform the following actions during ahot failover:• Save all forwarding information base (FIB) and content addressable memory (CAM) entries on the linecard and continue forwarding traffic while the secondary route processor module (RPM) is comingonline.• Advertise to all BGP neighbors and peer-groups that the forwarding state of all routes has been saved.This prompts all peers to continue saving the routes they receive and to continue forwarding traffic.• Bring the secondary RPM online as the primary and re-open sessions with all peers operating in NoShutdown mode.• Defer best path selection for a certain amount of time. This helps optimize path selection and resultsin fewer updates being sent out.To enable graceful restart, use the configure router bgp graceful-restart command.• Enable graceful restart for the BGP node.CONFIG-ROUTER-BGP modebgp graceful-restart• Set maximum restart time for all peers.CONFIG-ROUTER-BGP modebgp graceful-restart [restart-time time-in-seconds]The default is 120 seconds.• Set maximum time to retain the restarting peer’s stale paths.CONFIG-ROUTER-BGP mode188 Border Gateway Protocol IPv4 (BGPv4)
