From: "J. Bruce Fields" <bfields@fieldses.org>
To: Emmanuel Florac <eflorac@intellique.com>
Cc: linux-nfs@vger.kernel.org
Subject: Re: Hard to debug NFS loss of connectivity
Date: Tue, 10 Sep 2013 09:28:41 -0400 [thread overview]
Message-ID: <20130910132841.GC16011@fieldses.org> (raw)
In-Reply-To: <20130906185508.3f0d2730@harpe.intellique.com>
On Fri, Sep 06, 2013 at 06:55:08PM +0200, Emmanuel Florac wrote:
> Le Fri, 6 Sep 2013 12:07:35 -0400
> "J. Bruce Fields" <bfields@fieldses.org> écrivait:
>
> > Weird. Things look normal up through frame 14, which is a READDIRPLUS
> > reply. Then the server resends the reply after .2s, and and the
> > client resends its call shortly thereafter (but without acking the
> > latest reply). And then the rest of the trace is resends of the
> > reply.
> >
> > So it looks like the client stopped ACKing the server's replies?
> >
> > You may also have filtered out some TCP ACKs, which makes this harder
> > to work out.
>
> Ah yes, my bad, one TCP ACK was filtered out. Here I've kept trafic
> between the two machines but ssh.
Huh, no idea. You can see the server retransmitting the readdir plus
reply, and still no ACKs from the client.
> Here I was capturing from the server, maybe I should try capturing on
> the client side?
Sure, maybe.
Honestly looks like a network problem, if it weren't for the failing on
the filesystem operation each time.
Hm, it may just be the first packet of a certain size. In fact it's the
first frame > 1500 bytes in that trace. Is there some problem with
jumbo frame configuration on your network?
--b.
next prev parent reply other threads:[~2013-09-10 13:28 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-05 17:18 Hard to debug NFS loss of connectivity Emmanuel Florac
2013-09-05 20:45 ` J. Bruce Fields
2013-09-05 21:34 ` Emmanuel Florac
2013-09-05 21:40 ` J. Bruce Fields
2013-09-06 15:57 ` Emmanuel Florac
2013-09-06 16:07 ` J. Bruce Fields
2013-09-06 16:55 ` Emmanuel Florac
2013-09-10 13:28 ` J. Bruce Fields [this message]
2013-09-10 13:34 ` Emmanuel Florac
2013-09-06 17:15 ` Jim Rees
2013-09-11 15:11 ` Hard to debug NFS loss of connectivity: problem solved Emmanuel Florac
2013-09-11 20:14 ` J. Bruce Fields
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