we had same kind of issue - we looked into BFD dampening but it did not do what we needed - plus both end of a link need to support it. Cisco SE said that they would feed back our experience to the BU - never heard back though
One conversation on the topic. https://supportforums.cisco.com/document/144626/bfd-support-cisco-asr9000 Definitely interested is someone has managed to solve that problem with BFD dampening...without EEM scripts! On Thu, Apr 27, 2017 at 6:52 AM, Troy Boutso <[email protected]> wrote: > Hey all > > I have a fairly easy one for ya'll (I hope). > I have a network consisting of multiple WAN Links which span all over the > place. By WAN Links I am referring to private leased Layer 2 Circuits with > Ethernet Hand offs. > > Each of our client sites has two of these types of links via alternate > providers back to our 2 main "hub" sites. > > I am currently running. IS-IS (Level 2) with MPLS LDP and BFD for failure > detections on every single link. > iBGP (MP-BGP) is how I exchange all NLRI between sites... that all works > perfect. > > > I'll start off by saying 90% of the failures on my network involve one of > these links going down due to some fibre cut or other carrier transmission > issue. This is usually no big deal. As the BFD will detect the fault within > about 2 seconds and traffic re-routes instantly. I usually see a few > packets drop during this time. For what I do. This is completely > acceptable. > > However yesterday I was thrown a curveball. Rather than a particular link > simply going down. I saw it flap constantly for 2-5 minutes. Which is far > worse than I've experienced in the past. In the past this has happened, but > wasn't as bad (as in wasn't noticable for my customer). My model has stood > up ... until now. I understand what happened. I just don't know the best > way to address the issue and prevent it from being customer impacting. > > > The flaps i am referring to are NOT link state events. Meaning the > interfaces don't actually change state (the issue is somewhere in my > provider's end). Therefore I don't think "ip dampening" would help. What I > want is something at the BFD, ISIS level. To essentially poison/penalize or > even disable forwarding over link in question for a certain amount of time. > Until stability is maintained. And if the flapping persists, to continue > applying the penalty... (hope you all get what I am saying here) > > I looked into "BFD Dampening" which is configured under a template. But is > this really going to give me the desired result? Is there something else > out there that I've overlooked? > > If BFD damping is correct. I've got questions about the values :) > > > Kind Regards > Troy > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ > _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
