Did your BGP crash today?

Mikael Abrahamsson swmike at swm.pp.se
Sun Aug 29 07:23:49 UTC 2010


On Sat, 28 Aug 2010, Brett Frankenberger wrote:

> The implementor is to blame becuase the code he wrote send out BGP 
> messages which were not properly formed.

People talk about not dropping sessions but instead dropping malformed 
messages. This is not safe. We've seen ISIS (which is TLV based and *can* 
drop individual messages) been wrongly implemented and platforms drop the 
entire ISIS *packet* instead of the individual message when seeing 
something malformed (or rather in this case, ISIS multi topology which the 
implementation didn't understand), and this made the link state database 
go out of sync and miss information for things it actually should have 
understood.

This was *silent* error/corruption. I'm not sure I prefer to have silent 
problems instead of tearing down the session which is definitely 
noticable.

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se




More information about the NANOG mailing list