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Re: anyone else seeing very long AS paths?


From: Jack Bates <jbates () brightok net>
Date: Tue, 17 Feb 2009 13:19:00 -0600

German Martinez wrote:
On Tue Feb 17, 2009, Mike Lewinski wrote:

bgp max-as will NOT protect you from this exploit (but if you are not vulnerable it should prevent you from propogating it).

Are you trying to say that the receiving bgp speaker will drop the session
no matter what but it won't forward the update?

There are reports that some versions of IOS will drop a peer upon receiving the long AS, even with a bgp max-as command. I can only presume that there are some IOS versions that determine the update is invalid prior to the max-as command determining we are not keeping the route. The whole "is the update valid?" vs "do I want this in my routing table?"

Jack


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