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Establishing a Session on Physical Ports
To establish a session, enable BFD at the interface level on both ends of the link, as shown in the following illustration. The
configuration parameters do not need to match.
Figure 14. Establishing a BFD Session on Physical Ports
1. Enter interface mode.
CONFIGURATION mode
interface
2. Assign an IP address to the interface if one is not already assigned.
INTERFACE mode
ip address ip-address
3. Identify the neighbor that the interface participates with the BFD session.
INTERFACE mode
bfd neighbor ip-address
To verify that the session is established, use the show bfd neighbors command.
The bold line shows the BFD session.
R1(conf-if-te-1/1/4/1)#do show bfd neighbors
* - Active session role
Ad Dn - Admin Down
C - CLI
I - ISIS
O - OSPF
R - Static Route (RTM)
LocalAddr RemoteAddr Interface State Rx-int Tx-int Mult Clients
* 2.2.2.1 2.2.2.2 Te 1/1/4/1 Up 100 100 3 C
To view specific information about BFD sessions, use the show bfd neighbors detail command.
R1(conf-if-te-1/1/4/1)#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 1/1/4/1
State: Up
Configured parameters:
TX: 100ms, RX: 100ms, Multiplier: 3
Neighbor parameters:
TX: 100ms, RX: 100ms, Multiplier: 3
Actual parameters:
TX: 100ms, RX: 100ms, Multiplier: 3
Role: Active
Delete session on Down: False
Bidirectional Forwarding Detection (BFD)
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