Administrator Guide

Example of Viewing Session Parameters
R1(conf-if-te-4/24)#bfd interval 100 min_rx 100 multiplier 4 role passive
R1(conf-if-te-4/24)#do show bfd neighbors detail
Session Discriminator: 1
Neighbor Discriminator: 1
Local Addr: 2.2.2.1
Local MAC Addr: 00:01:e8:09:c3:e5
Remote Addr: 2.2.2.2
Remote MAC Addr: 00:01:e8:06:95:a2
Int: TenGigabitEthernet 4/24
State: Up
Configured parameters:
TX: 100ms, RX: 100ms, Multiplier: 4
Neighbor parameters:
TX: 100ms, RX: 100ms, Multiplier: 3
Actual parameters:
TX: 100ms, RX: 100ms, Multiplier: 4
Role:
Passive
Delete session on Down: False
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-te-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 Te 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 Te 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.
Bidirectional Forwarding Detection (BFD)
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