OSPF BFD Query

[Steev112]

Hello,

i have one query regarding to configure OSPF BFD feaure for only one interface the scenario is,

i have three routers, i just want to configure the BFD on the interface between R2 and R1 as showing below:

R1 ---------- R2 ---------- R3

my question is can i only enable this feaure on R2 interface and R1  not for exampe:

Configuration for R2

!interface Fast Ethernet 0/1

ip address 172.16.10.1 255.255.255.0

bfd interval 50 min_rx 50 multiplier 3

!

interface Fast Ethernet 3/0.1

ip address 172.17.0.1 255.255.255.0

!

router ospf 123

log-adjacency-changes detail

network 172.16.0.0 0.0.0.255 area 0

network 172.17.0.0 0.0.0.255 area 0

bfd all-interfaces

Configuration for R1

!

interface Fast Ethernet 6/0

ip address 172.16.10.2 255.255.255.0

!

interface Fast Ethernet 6/1

ip address 172.18.0.1 255.255.255.0

!

router ospf 123

log-adjacency-changes detail

network 172.16.0.0 0.0.255.255 area 0

network 172.18.0.0 0.0.255.255 area 0

as showed in the above example on R1 not configured BFD.

it will work or i must enable both

Thanks,

[Reza Sharifi]

Hi,

What devices are you using and what version of software?

[Steev112]

Hello ,

as understood i must enabled between the two neighbors,  if only one interface enabled BFD the ospf neighbor will not come up.correct me ?

Thanks

[Steev112]

Hello All,

i have 4500x and under ospf i didn't  able to add

router ospf 123
bfd interface fastethernet6/0

can i enable it only under the interface as follow:

interface f6/0

ip ospf bfd

and I should enable the same BFD value on both neighbors. if there is any document mentioned this please share it.

Thanks

[Akash Agrawal · Accepted solution]

Hi,

Which IOS you are running. Please go through below CCO document for configuration help enabling BFD for OSPF on 4500E

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/15-1/XE_330SG/configuration/guide/config/bfd.html#wp1056004

snippet

Note Support on the Catalyst 4500E is limited. Starting with Cisco IOS Release IOS 15.1(1)SG, Bidirectional Forwarding Detection (BFD) is supported only on Catalyst 4900M, and Catalyst 4948E Ethernet switches.

--Pls dont forget to rate helpful posts--

Regards,

Akash

[Steev112]

Thanks Akash for your support.

[Akash Agrawal]

Hi,

I guess it should be running on all participating routers. When we configure BFD below command

"bfd interval 50 min_rx 50 multiplier 3", it says that router will send BFD packet every 50ms and would expect BFD packet every 50ms (min_rx). If does not receive BFD for 3 consecutive time, it will announce neighbor as down. So for other router to send BFD hello, it is required to configure BFD there.

--Pls dont forget to rate helpful posts--

Regards,

Akash

[danrya]

Change bfd all-interface under OSPF to the interface you want to run BFD on.

On router 2, change this:

router ospf 123
 bfd all-interfaces

To this:

router ospf 123
 bfd interface fastethernet0/1

and add this to R1:

router ospf 123
 bfd interface fastethernet6/0

That should do it.