[129133] in North American Network Operators' Group
Re: Did your BGP crash today?
daemon@ATHENA.MIT.EDU (Dave Israel)
Fri Aug 27 15:33:56 2010
Date: Fri, 27 Aug 2010 15:33:38 -0400
From: Dave Israel <davei@otd.com>
To: nanog@nanog.org
In-Reply-To: <CECF8313-7BCE-412F-BDBD-36D9B44CA1BF@puck.nether.net>
X-otd-MailScanner-From: davei@otd.com
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On 8/27/2010 3:22 PM, Jared Mauch wrote:
> When you are processing something, it's sometimes hard to tell if something
> just was mis-parsed (as I think the case is here with the "missing-2-bytes")
> vs just getting garbage. Perhaps there should be some way to "re-sync" when
> you are having this problem, or a parallel "keepalive" path similar to
> MACA/MCAS/MIDCAS/TCAS between the devices to talk when something bad is
> happening.
I know it wasn't there originally, and isn't mandatory now, but there is
an MD5 hash that can be added to the packet. If the TCP hash checks
out, then you know the packet wasn't garbled, and just contained
information you didn't grok. That seems like enough evidence to be able
to shrug and toss the packet without dropping the session.
-Dave
