Reference Guide

To view detailed session information, use the show bfd neighbors detail command, as shown in the examples in
Displaying BFD for BGP Information.
Changing Static Route Session Parameters
BFD sessions are configured with default intervals and a default role.
The parameters you can configure are: Desired TX Interval, Required Min RX Interval, Detection Multiplier, and system role.
These parameters are configured for all static routes. If you change a parameter, the change affects all sessions for static
routes.
To change parameters for static route sessions, use the following command .
● Change parameters for all static route sessions.
CONFIGURATION mode
ip route bfd interval milliseconds min_rx milliseconds multiplier value role [active |
passive]
To view session parameters, use the show bfd neighbors detail command, as shown in the examples in Displaying BFD
for BGP Information.
Disabling BFD for Static Routes
If you disable BFD, all static route BFD sessions are torn down.
A final Admin Down packet is sent to all neighbors on the remote systems, and those neighbors change to the Down state.
To disable BFD for static routes, use the following command.
● Disable BFD for static routes.
CONFIGURATION mode
no ip route bfd
Configure BFD for OSPF
When using BFD with OSPF, the OSPF protocol registers with the BFD manager. BFD sessions are established with all
neighboring interfaces participating in OSPF. If a neighboring interface fails, the BFD agent on the line card notifies the BFD
manager, which in turn notifies the OSPF protocol that a link state change occurred.
NOTE:
If you enable BFD after OSPF with a large number (more than 100) of OSPF neighbors on a VLAN port-channel and if the
VLAN has more than one port-channel, BFD does not come up immediately. (This behavior occurs only if you enable BFD
after connections with all OSPF neighbors are fully established.)
BFD does not come up for 5 to 6 minutes in a scenario when all the following conditions are met:
● A large number of BFD neighbors are present.
● The neighbors are reachable over a VLAN through a port-channel and the VLAN has multiple port-channels as members.
● BFD is enabled after all the OSPF neighbors are in an established state.
This delay should not be seen after a reload because OSPF will throttle neighbor establishment.
Configuring BFD for OSPF is a two-step process:
1. Enable BFD globally.
2. Establish sessions with OSPF neighbors.
Related Configuration Tasks
● Changing OSPF Session Parameters
Bidirectional Forwarding Detection (BFD)
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