Dell C9000 Series Networking Configuration Manual page 182

session (other routing protocols) about the failure. It then depends on the individual routing protocols that
uses the BGP link to determine the appropriate response to the failure condition. The typical response is to
terminate the peering session for the routing protocol and reconverge by bypassing the failed neighboring
router. A log message is generated whenever BFD detects a failure condition.
1 Enable BFD globally.
CONFIGURATION mode
bfd enable
2 Specify the AS number and enter ROUTER BGP configuration mode.
CONFIGURATION mode
router bgp as-number
3 Add a BGP neighbor or peer group in a remote AS.
CONFIG-ROUTERBGP mode
neighbor {ip-address | peer-group name} remote-as as-number
4 Enable the BGP neighbor.
CONFIG-ROUTERBGP mode
neighbor {ip-address | peer-group-name} no shutdown
5 Configure parameters for a BFD session established with all neighbors discovered by BGP. OR Establish
a BFD session with a specified BGP neighbor or peer group using the default BFD session parameters.
CONFIG-ROUTERBGP mode
bfd all-neighbors [interval millisecs min_rx millisecs multiplier value role
{active | passive}]
OR
neighbor {ip-address | peer-group-name} bfd
NOTES:
• When you establish a BFD session with a specified BGP neighbor or peer group using the
neighbor bfd command, the default BFD session parameters are used (interval: 200
milliseconds, min_rx: 200 milliseconds, multiplier: 3 packets, and role: active).
• When you explicitly enable or disable a BGP neighbor for a BFD session with the neighbor bfd or
neighbor bfd disable commands, the neighbor does not inherit the BFD enable/disable values
configured with the bfd all-neighbors command or configured for the peer group to which
the neighbor belongs. Also, the neighbor only inherits the global timer values configured with the
bfd all-neighbors command (interval, min_rx, and multiplier).
6 Repeat Steps 1 to 5 on each BGP peer participating in a BFD session.
Disabling BFD for BGP
You can disable BFD for BGP.
To disable a BFD for BGP session with a specified neighbor, use the first command. To remove the disabled
state of a BFD for BGP session with a specified neighbor, use the second command.
The BGP link with the neighbor returns to normal operation and uses the BFD session parameters globally
configured with the bfd all-neighbors command or configured for the peer group to which the neighbor
belongs.
Bidirectional Forwarding Detection (BFD) 182