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The BFD-EIGRP Support feature configures the Enhanced Interior Gateway Routing Protocol (EIGRP) with Bidirectional Forwarding Detection (BFD) so that EIGRP registers with BFD and receives all forwarding path detection failure messages from BFD.
Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.
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The BFD-EIGRP Support feature configures Bidirectional Forwarding Detection (BFD) feature for Enhanced Interior Gateway Routing Protocol (EIGRP) so that EIGRP registers with the BFD sessions on the routing interfaces, and receives forwarding path detection failure messages from BFD.
Use bfd interval milliseconds min_rx milliseconds multiplier interval-multiplier command to enable BFD on any interface. Use the bfd all-interfaces command in router configuration mode to enable BFD for all of the interfaces where EIGRP routing is enabled. Use the bfd interface type number command in router configuration mode to enable BFD for a subset of the interfaces where EIGRP routing is enabled.
1.
enable
2.
configure
terminal
3.
router
eigrp
as-number
5.
end
6.
show
bfd
neighbors
[details]
7.
show
ip
eigrp
interfaces
[type
number]
[as-number]
[detail]
In the following example, the EIGRP network contains DeviceA, DeviceB, and DeviceC. Fast Ethernet interface 1/0 on DeviceA is connected to the same network as Fast Ethernet interface 1/0 on Device B. Fast Ethernet interface 1/0 on DeviceB is connected to the same network as Fast Ethernet interface 1/0 on DeviceC.
DeviceA and DeviceB are running BFD Version 1, which supports echo mode, and DeviceC is running BFD Version 0, which does not support echo mode. The BFD sessions between DeviceC and its BFD neighbors are said to be running echo mode with asymmetry because echo mode will run on the forwarding path for DeviceA and DeviceB, and their echo packets will return along the same path for BFD sessions and failure detections, while their BFD neighbor DeviceC runs BFD Version 0 and uses BFD controls packets for BFD sessions and failure detections.
The figure below shows a large EIGRP network with several devices, three of which are BFD neighbors that are running EIGRP as their routing protocol.
The example, starting in global configuration mode, shows the configuration of BFD.
interface Fast Ethernet0/0 no shutdown ip address 10.4.9.14 255.255.255.0 duplex auto speed auto ! interface Fast Ethernet1/0 ip address 172.16.1.1 255.255.255.0 bfd interval 50 min_rx 50 multiplier 3 no shutdown duplex auto speed auto ! router eigrp 11 network 172.16.0.0 bfd all-interfaces auto-summary ! ip default-gateway 10.4.9.1 ip default-network 0.0.0.0 ip route 0.0.0.0 0.0.0.0 10.4.9.1 ip route 172.16.1.129 255.255.255.255 10.4.9.1 ! no ip http server ! logging alarm informational ! control-plane ! line con 0 exec-timeout 30 0 stopbits 1 line aux 0 stopbits 1 line vty 0 4 login ! ! end
! interface Fast Ethernet0/0 no shutdown ip address 10.4.9.34 255.255.255.0 duplex auto speed auto ! interface Fast Ethernet1/0 ip address 172.16.1.2 255.255.255.0 bfd interval 50 min_rx 50 multiplier 3 no shtdown duplex auto speed auto ! router eigrp 11 network 172.16.0.0 bfd all-interfaces auto-summary ! ip default-gateway 10.4.9.1 ip default-network 0.0.0.0 ip route 0.0.0.0 0.0.0.0 10.4.9.1 ip route 172.16.1.129 255.255.255.255 10.4.9.1 ! no ip http server ! logging alarm informational ! control-plane ! line con 0 exec-timeout 30 0 stopbits 1 line aux 0 stopbits 1 line vty 0 4 login ! ! end
! ! interface Fast Ethernet0/0 no shutdown ip address 10.4.9.34 255.255.255.0 duplex auto speed auto ! interface Fast Ethernet1/0 ip address 172.16.1.2 255.255.255.0 bfd interval 50 min_rx 50 multiplier 3 no shutdown duplex auto speed auto ! router eigrp 11 network 172.16.0.0 bfd all-interfaces auto-summary ! ip default-gateway 10.4.9.1 ip default-network 0.0.0.0 ip route 0.0.0.0 0.0.0.0 10.4.9.1 ip route 172.16.1.129 255.255.255.255 10.4.9.1 ! no ip http server ! logging alarm informational ! control-plane ! line con 0 exec-timeout 30 0 stopbits 1 line aux 0 stopbits 1 line vty 0 4 login ! ! end
The output from the show bfd neighbors details command from DeviceA verifies that BFD sessions are created among all three devices and that EIGRP is registered for BFD support. The first group of output shows that DeviceC with the IP address 172.16.1.3 runs BFD Version 0 and therefore does not use the echo mode. The second group of output shows that DeviceB with the IP address 172.16.1.2 runs BFD Version 1, and the 50 millisecond BFD interval parameter had been adopted. The relevant command output is shown in bold in the output.
DeviceA# show bfd neighbors details OurAddr NeighAddr LD/RD RH/RS Holdown(mult) State Int 172.16.1.1 172.16.1.3 5/3 1(RH) 150 (3 ) Up Fa1/0 Session state is UP and not using echo function. Local Diag: 0, Demand mode: 0, Poll bit: 0 MinTxInt: 50000, MinRxInt: 50000, Multiplier: 3 Received MinRxInt: 50000, Received Multiplier: 3 Holdown (hits): 150(0), Hello (hits): 50(1364284) Rx Count: 1351813, Rx Interval (ms) min/max/avg: 28/64/49 last: 4 ms ago Tx Count: 1364289, Tx Interval (ms) min/max/avg: 40/68/49 last: 32 ms ago Registered protocols: EIGRP Uptime: 18:42:45 Last packet: Version: 0 - Diagnostic: 0 I Hear You bit: 1 - Demand bit: 0 Poll bit: 0 - Final bit: 0 Multiplier: 3 - Length: 24 My Discr.: 3 - Your Discr.: 5 Min tx interval: 50000 - Min rx interval: 50000 Min Echo interval: 0 OurAddr NeighAddr LD/RD RH/RS Holdown(mult) State Int 172.16.1.1 172.16.1.2 6/1 Up 0 (3 ) Up Fa1/0 Session state is UP and using echo function with 50 ms interval. Local Diag: 0, Demand mode: 0, Poll bit: 0 MinTxInt: 1000000, MinRxInt: 1000000, Multiplier: 3 Received MinRxInt: 1000000, Received Multiplier: 3 Holdown (hits): 3000(0), Hello (hits): 1000(317) Rx Count: 305, Rx Interval (ms) min/max/avg: 1/1016/887 last: 448 ms ago Tx Count: 319, Tx Interval (ms) min/max/avg: 1/1008/880 last: 532 ms ago Registered protocols: EIGRP Uptime: 00:04:30 Last packet: Version: 1 - Diagnostic: 0 State bit: Up - Demand bit: 0 Poll bit: 0 - Final bit: 0 Multiplier: 3 - Length: 24 My Discr.: 1 - Your Discr.: 6 Min tx interval: 1000000 - Min rx interval: 1000000 Min Echo interval: 50000
The output from the show bfd neighbors details command on Device B verifies that BFD sessions have been created and that EIGRP is registered for BFD support. As previously noted, DeviceA runs BFD Version 1, therefore echo mode is running, and DeviceC runs BFD Version 0, so echo mode does not run. The relevant command output is shown in bold in the output.
DeviceB# show bfd neighbors details OurAddr NeighAddr LD/RD RH/RS Holdown(mult) State Int 172.16.1.2 172.16.1.1 1/6 Up 0 (3 ) Up Fa1/0 Session state is UP and using echo function with 50 ms interval. Local Diag: 0, Demand mode: 0, Poll bit: 0 MinTxInt: 1000000, MinRxInt: 1000000, Multiplier: 3 Received MinRxInt: 1000000, Received Multiplier: 3 Holdown (hits): 3000(0), Hello (hits): 1000(337) Rx Count: 341, Rx Interval (ms) min/max/avg: 1/1008/882 last: 364 ms ago Tx Count: 339, Tx Interval (ms) min/max/avg: 1/1016/886 last: 632 ms ago Registered protocols: EIGRP Uptime: 00:05:00 Last packet: Version: 1 - Diagnostic: 0 State bit: Up - Demand bit: 0 Poll bit: 0 - Final bit: 0 Multiplier: 3 - Length: 24 My Discr.: 6 - Your Discr.: 1 Min tx interval: 1000000 - Min rx interval: 1000000 Min Echo interval: 50000 OurAddr NeighAddr LD/RD RH/RS Holdown(mult) State Int 172.16.1.2 172.16.1.3 3/6 1(RH) 118 (3 ) Up Fa1/0 Session state is UP and not using echo function. Local Diag: 0, Demand mode: 0, Poll bit: 0 MinTxInt: 50000, MinRxInt: 50000, Multiplier: 3 Received MinRxInt: 50000, Received Multiplier: 3 Holdown (hits): 150(0), Hello (hits): 50(5735) Rx Count: 5731, Rx Interval (ms) min/max/avg: 32/72/49 last: 32 ms ago Tx Count: 5740, Tx Interval (ms) min/max/avg: 40/64/50 last: 44 ms ago Registered protocols: EIGRP Uptime: 00:04:45 Last packet: Version: 0 - Diagnostic: 0 I Hear You bit: 1 - Demand bit: 0 Poll bit: 0 - Final bit: 0 Multiplier: 3 - Length: 24 My Discr.: 6 - Your Discr.: 3 Min tx interval: 50000 - Min rx interval: 50000 Min Echo interval: 0
The figure below shows that Fast Ethernet interface 1/0 on DeviceB has failed. When Fast Ethernet interface 1/0 on DeviceB is shut down, the BFD statistics of the corresponding BFD sessions on DeviceA and DeviceB are reduced.
When Fast Ethernet interface 1/0 on DeviceB fails, BFD will no longer detect Device B as a BFD neighbor for DeviceA or for DeviceC. In this example, Fast Ethernet interface 1/0 has been administratively shut down on DeviceB.
The following output from the show bfd neighbors command on DeviceA now shows only one BFD neighbor for DeviceA in the EIGRP network. The relevant command output is shown in bold in the output.
DeviceA# show bfd neighbors OurAddr NeighAddr LD/RD RH/RS Holdown(mult) State Int 172.16.1.1 172.16.1.3 5/3 1(RH) 134 (3 ) Up Fa1/0
The following output from the show bfd neighbors command on DeviceC also now shows only one BFD neighbor for DeviceC in the EIGRP network. The relevant command output is shown in bold in the output.
DeviceC# show bfd neighbors OurAddr NeighAddr LD/RD RH Holdown(mult) State Int 172.16.1.3 172.16.1.1 3/5 1 114 (3 ) Up Fa1/0
Related Topic | Document Title |
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BFD Commands |
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Cisco IOS Commands |
Description | Link |
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The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Feature Name |
Releases |
Feature Information |
---|---|---|
BFD-EIGRP Support |
15.2(1)E |
The BFD-EIGRP Support feature configures the Enhanced Interior Gateway Routing Protocol (EIGRP) with Bidirectional Forwarding Detection (BFD) so that EIGRP registers with BFD and receives all forwarding path detection failure messages from BFD. |