I am also a bit leery of setting it much lower than the defaults due to the possibility of filtering something my customers will care about... I am not sure what the best strategy is but what really bit a couple of our customers was their old IOSes that tore the sessions down. I note that most of our customers speaking BGP had no issue just three out of about 25. What do people think is a reasonable maximum as-path length to enforce at ones edge? John van Oppen Spectrum Networks LLC Direct: 206.973.8302 Main: 206.973.8300 Website: http://spectrumnetworks.us -----Original Message----- From: Leland E. Vandervort [mailto:leland@taranta.discpro.org] Sent: Monday, February 16, 2009 9:53 AM To: Jon Lewis Cc: John van Oppen; nanog@nanog.org Subject: RE: anyone else seeing very long AS paths? bgp maxas-limit has a default value of 75 if you don't include it explicitly in the config so in this case it wouldn't have made much of a difference. L. On Mon, 16 Feb 2009, Jon Lewis wrote:
On Mon, 16 Feb 2009, John van Oppen wrote:
Yep we saw the same, every customer with old IOS had their sessions die to us at the same time... That always makes for an interesting time when watching the NMS system...
Is there a reason you don't use something like "bgp maxas-limit NN" on your transit sessions?
We saw this too, but it stopped at our transit routers. There was actually another a few days ago.
Feb 13 18:46:07: %BGP-6-ASPATH: Long AS path 4323 1299 12887 12741 39412 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625...
Feb 16 11:24:53: %BGP-6-ASPATH: Long AS path 4323 3257 29113 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868...
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