Administrator Guide

Client Registered: CLI
Uptime: 00:09:06
Statistics:
Number of packets received from neighbor: 4092
Number of packets sent to neighbor: 4093
Number of state changes: 1
Number of messages from IFA about port state change: 0
Number of messages communicated b/w Manager and Agent:
7
Disabling and Re-Enabling BFD
BFD is enabled on all interfaces by default, though sessions are not created unless explicitly congured.
If you disable BFD, all of the sessions on that interface are placed in an Administratively Down state ( the rst message example),
and the remote systems are notied of the session state change (the second message example).
To disable and re-enable BFD on an interface, use the following commands.
• Disable BFD on an interface.
INTERFACE mode
no bfd enable
• Enable BFD on an interface.
INTERFACE mode
bfd enable
If you disable BFD on a local interface, this message displays:
R1(conf-if-gi-4/24)#01:00:52: %RPM0-P:RP2 %BFDMGR-1-BFD_STATE_CHANGE: Changed session
state to Ad
Dn for neighbor 2.2.2.2 on interface Gi 4/24 (diag: 0)
If the remote system state changes due to the local state administration being down, this message displays:
R2>01:32:53: %RPM0-P:RP2 %BFDMGR-1-BFD_STATE_CHANGE: Changed session state to Down for
neighbor
2.2.2.1 on interface Gi 2/1 (diag: 7)
Congure BFD for Static Routes
BFD oers systems a link state detection mechanism for static routes.
With BFD, systems are notied to remove static routes from the routing table as soon as the link state change occurs, rather than
waiting until packets fail to reach their next hop.
Conguring BFD for static routes is a three-step process:
1. Enable BFD globally. Refer to Enabling BFD Globally.
2. On the local system, establish a session with the next hop of a static route. Refer to Establishing Sessions for Static Routes.
3. On the remote system, establish a session with the physical port that is the origin of the static route. Refer to Establishing a
Session on Physical Ports.
Related Conguration Tasks
• Changing Static Route Session Parameters
• Disabling BFD for Static Routes
Bidirectional Forwarding Detection (BFD)
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