I finally decided to shut down all peerings and brought them back one by one. Everything is stable again, but I don't like the way I had to deal with it since it will most likely happen again when DECIX or an other IX we're at is having issues. I've seen a few BGP convergence discussions on NANOG, but none about deadlock situations and what could be done to avoid them. Setting higher MTU or bigger hold queues did not help. - Andy On Tue, Jun 8, 2010 at 2:35 PM, Ingo Flaschberger <if@xip.at> wrote:
Dear Andy
This morning there was an ethernet loop problem on DECIX, causing many BGP sessions to flap throughout the entire platform. While this can happen, I am myself facing with BGP convergence problems on our DECIX router (SUP720-3BXL with IOS SXI3).
De DECIX loop has been solved two hours ago, but my BGP sessions are still flapping and not converging at all. This has been flooding our logs, and is still going on:
route half or more of the peering-network to Null -> lowering bgp session up's. (at the other side, your bgp-router seems to be overloaded).
Kind regards, Ingo Flaschberger