Reference Guide

Bidirectional Forwarding Detection (BFD) | 141
To remove the disabled state of a BFD for BGP session with a specified neighbor, enter the no neighbor
{ip-address | peer-group-name} bfd disable command in ROUTER BGP configuration mode. 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.
Using BFD in a BGP Peer Group
If you establish a BFD session for the members of a peer group (neighbor peer-group-name bfd command
in ROUTER BGP configuration mode), members of the peer group may have BFD:
• Explicitly enabled (
neighbor ip-address bfd command)
• Explicitly disabled (
neighbor ip-address bfd disable command)
• Inherited (neither explicitly enabled or disabled) according to the current BFD configuration of the
peer group. For information on BGP peer groups, see Configure Peer Groups.
If you explicitly enable (or disable) a BGP neighbor for BFD that belongs to a peer group:
• 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.
• The neighbor inherits only the global timer values that are configured with the
bfd all-neighbors
command (interval, min_rx, and multiplier).
If you explicitly enable (or disable) a peer group for BFD that has no BFD parameters configured (e.g.
advertisement interval) using the
neighbor peer-group-name bfd command, the peer group inherits any
BFD settings configured with the
bfd all-neighbors command.
Displaying BFD for BGP Information
To display information about BFD for BGP sessions on a router, enter one of the following show
commands:
Task Command Command Mode
Verify a BFD for BGP configuration. show running-config bgp
Figure 7-16
EXEC Privilege
Verify that a BFD for BGP session has been
successfully established with a BGP neighbor. A
line-by-line listing of established BFD
adjacencies is displayed.
show bfd neighbors [interface] [detail]
Figure 7-17 and Figure 7-18
EXEC Privilege
Display BFD packet counters for sessions with
BGP neighbors.
show bfd counters bgp [interface]
Figure 7-19
EXEC Privilege
Check to see if BFD is enabled for BGP
connections.
show ip bgp summary
Figure 7-20
EXEC Privilege
Displays routing information exchanged with
BGP neighbors, including BFD for BGP
sessions.
show ip bgp neighbors [ip-address]
Figure 7-21
EXEC Privilege