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Re: Survey on IBGP persistent route oscillation problem
[email protected] disait : > > We have a similar situation (RR + always-compare-MED off), and the BGP table > > version keeps changing at 1K/min (http://performance.cn.net:2003/). I > > suspect some > > route meet the criteria of IDR-oscillation draft. But in real world, it's > > very hard to pick > > up the pattern depicted in the draft from a huge log of debug bgp output. > > It's actually quite trivial to identify. Have a look at: > > http://www.cisco.com/warp/public/770/fn12942.html As Yu said, it is not so easy. Most of the output in "show ip route bgp | include , 00:00" command match flapping updates that are getting "dampening candidates" !! Beside, you have to run the command on a router that might hit the problem .... it depends a lot on your peering locations and partners. If you run Cisco commands on wrong router, you would not see any problem and may get in wrong conclusion !! > > 2. From my experience, most flapping seems to be oscillation route > > which escaped the eBGP damping protection. And for this, we need > > adjust damping parameters from RIPE 220 to make up. > > Nope. Dampening doesn't resolve this because it occurs > intrA-domain. Does not fix, but it would lower updates thus help to identify update loops. Vincent.