netdev - Re: TCP keepalives ignored by kernel when the contain timestamps

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Message-ID: <1307722621.4044.17.camel@edumazet-laptop>
Date:	Fri, 10 Jun 2011 18:17:01 +0200
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Charles Bearden <Charles.F.Bearden@....tmc.edu>
Cc:	netdev@...r.kernel.org
Subject: Re: TCP keepalives ignored by kernel when the contain timestamps

Le vendredi 10 juin 2011 à 11:07 -0500, Charles Bearden a écrit :

> You are correct: the checksums in the keepalives are broken, though they are 
> correct in the other segments from the Win2008 server. I have updated the pastes 
> linked to above with 'tcpdump -v' output. I apologize for missing that problem 
> the first time around.

Hmm, maybe its OK : If checksums are offloaded to NIC, tcpdump 'lies'
telling checksum is not OK, since tcpdump get a copy of the packet
before being handled by the NIC.

You should take a tcpdump on the receiving machine (the machine that
apparently doesnt react to the keepalive probes)


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