anyone else seeing very long AS paths?

Jack Bates jbates at brightok.net
Tue Feb 17 19:19:00 UTC 2009


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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