Users Guide

• Establish BFD sessions with all neighbors discovered by BGP using the bfd all-neighbors command.
For example:
Router 1
OS10(conf)# bfd enable
OS10(conf)# router bgp 1
OS10(config-router-bgp-1)# neighbor 2.2.4.3
OS10(config-router-neighbor)# bfd
OS10(config-router-neighbor)# no shutdown
OR
OS10(conf)# bfd enable
OS10(conf)# router bgp 1
OS10(config-router-bgp-1)# bfd all-neighbors interval 200 min_rx 200 multiplier 6 role active
Router 2
OS10(conf)# bfd enable
OS10(conf)# router bgp 2
OS10(config-router-bgp-2)# neighbor 2.2.4.2
OS10(config-router-neighbor)# bfd
OS10(config-router-neighbor)# no shutdown
OR
OS10(conf)# bfd enable
OS10(conf)# router bgp 2
OS10(conf-router-bgp-2)# bfd all-neighbors interval 200 min_rx 200 multiplier 6 role active
BFD packets originating from a router are assigned to the highest priority egress queue to minimize transmission delays. Incoming BFD
control packets received from the BGP neighbor are assigned to the highest priority queue within the control plane policing (CoPP)
framework to avoid BFD packets drops due to queue congestion.
BFD noties BGP of any failure conditions that it detects on the link. BGP initiates recovery actions.
BFD for BGP is supported only on directly connected BGP neighbors and in both BGP IPv4 and IPV6 networks. A maximum of 100
simultaneous BFD sessions are supported.
If each BFD for BGP neighbor receives a BFD control packet within the congured BFD interval for failure detection, the BFD session
remains up and BGP maintains its adjacencies. If a BFD for BGP neighbor does not receive a control packet within the detection interval,
the router informs any clients of the BFD session, and other routing protocols, about the failure. It then depends on the routing protocol
that uses the BGP link to determine the appropriate response to the failure condition. The normal response is to terminate the peering
session for the routing protocol and reconverge by bypassing the failed neighboring router. A log message generates whenever BFD
detects a failure condition.
Congure BFD for BGP
OS10 supports BFD sessions with IPv4 or IPv6 BGP neighbors using the default VRF. When you congure BFD for BGP, you can enable
BFD sessions with all BGP neighbors discovered by BGP or with a specied neighbor.
1 Congure BFD session parameters and enable BFD globally on all interfaces in CONFIGURATION mode as described in Congure BFD
globally.
bfd interval milliseconds min_rx milliseconds multiplier number role {active | passive}
bfd enable
2 Enter the AS number of a remote BFD peer in CONFIGURATION mode, from 1 to 65535 for a 2-byte AS number and from 1 to
4294967295 for a 4-byte AS number. Only one AS number is supported per system. If you enter a 4-byte AS number, 4-byte AS
support enables automatically.
router bgp as-number
3 Enter the IP address of a BFD peer in ROUTER-BGP mode. Enable a BFD session and the BGP link in ROUTER-NEIGHBOR mode.
The global BFD session parameters congured in Step 1 are used.
neighbor ip-address
bfd
no shutdown
Layer 3
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