Example: Configuring Bfd In An Ospf Network - Cisco Catalyst 4500 Series Configuration Manual

Chapter 37 Configuring Bidirection Forwarding Detection
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Last packet: Version: 0
Figure 37-4
interface 6/1 on SwitchB is shut down, the BFD values of the corresponding BFD sessions on SwitchA
and SwitchB are reduced.
Figure 37-4
When Gigabit Ethernet interface 6/1 on SwitchB fails, BFD will no longer detect SwitchB as a BFD
neighbor for SwitchA or for SwitchC. In this example, Gigabit Ethernet interface 6/1 has been
administratively shut down on SwitchB.
The following output from the show bfd neighbors command on SwitchA now shows only one BFD
neighbor for SwitchA in the EIGRP network. The relevant command output is shown in bold in the
output.
SwitchA# show bfd neighbors
OurAddr
172.16.1.1
The following output from the show bfd neighbors command on SwitchC also now shows only one BFD
neighbor for SwitchC in the EIGRP network. The relevant command output is shown in bold in the
output.
SwitchC# show bfd neighbors
OurAddr
172.16.1.3

Example: Configuring BFD in an OSPF Network

The following example shows how to configure BFD in an OSPF network in Cisco IOS
Release 15.1(1)SG. In the following example, the simple OSPF network consists of SwitchA and
SwitchB. Gigabit Ethernet interface 6/1 on SwitchA is connected to the same network as Gigabit
OL-25340-01
I Hear You bit: 1
Poll bit: 0
Multiplier: 3
My Discr.: 6
Min tx interval: 50000
Min Echo interval: 0
shows that Gigabit Ethernet interface 6/1 on SwitchB has failed. When Gigabit Ethernet
Gigabit Ethernet Interface 6/1 Failure
SwitchB
172.16.1.2
172.16.1.1
GigabitEthernet 6/1
SwitchA
LD/RD
NeighAddr
172.16.1.3 5/3
NeighAddr LD/RD RH
172.16.1.1 3/5
Software Configuration Guide—Release IOS XE 3.3.0SG and IOS 15.1(1)SG
Configuration Examples for Bidirectional Forwarding Detection
- Diagnostic: 0
- Demand bit: 0
- Final bit: 0
- Length: 24
- Your Discr.: 3
- Min rx interval: 50000
Gigabit Ethernet 6/1
icon indicating a failure
172.16.1.3
GigabitEthernet 6/1
RH/RS Holdown(mult)
1(RH) 134 (3 )
Holdown(mult) State
1 114 (3 ) Up
SwitchC
State Int
Up Gi6/1
Int
Gi6/1
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