LDP convergence using BFD

Unanswered Question
Jun 24th, 2009

Can I used BFD for LDP convergence. Can anyone explain way convegence will happen in my mpls core. If I am using BFD for triggering my IGP convergence. With BFD hello timers of 50ms & hold timer of 150 ms.

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Overall Rating: 4 (2 ratings)
Laurent Aubert Thu, 06/25/2009 - 18:16


Two feature can help for LDP convergence:

- LDP session protection

- MPLS LDP-IGP Sync (which makes the first feature less useful).

It's still your IGP (except if TE is used) which will provide the path between two points.



jcozzupoli Mon, 06/29/2009 - 05:39

hey Anil,

Any update on this one? Have we helped in anyway?



anil12345 Mon, 06/29/2009 - 21:26

yes in some ways. My vendor was claiming to have subsecond convergence using plain BFD based IGP, LDP & BGP convergence in my MPLS backbone for link & node failure.

Just not sure how will they aceive it without implementing MPLS TE FRR.

amit.bhagat Tue, 06/30/2009 - 21:09

Can we configure BFD for LDP LSPs? I believe Junos lets you do that.

Laurent Aubert Wed, 07/01/2009 - 08:39


We don't support BFD for LDP but BFD for MPLS OAM (L2 and L3) is on the road-map (check with your account team for more details)

Assuming you have redundant path, you can use BFD for fast link detection or for MPLS-TE FRR trigger. Use LDP-IGP sync for Down-to-UP event or if you loose your LDP session.



Jaweedshaikh Thu, 07/02/2009 - 16:39

Hi All,

Is there anytoher technique under BGP timer besides Hold timer and Keepalive that can improve convergence in MPLS L3 VPN network.

I know about BFD, some work is going on under BGP timer side to improve convergence


jcozzupoli Thu, 07/02/2009 - 20:33


One way to add improvements to your MPLS L3 VPN network is to add the "bgp scan-time" command under the BGP process address-family configuration.

What this command does is set the scanning intervals of BGP next-hop validation or to decrease import processing time of VPNv4 routing info.

jcozzupoli Sun, 07/19/2009 - 04:01


Have we answered your questions? Can you please rate now if you are finished with this forum.




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