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From: "/dev/rob0" <rob0@gmx.co.uk>
To: netfilter@vger.kernel.org
Subject: Re: Poor upload speed with NAT
Date: Tue, 11 Aug 2009 10:29:40 -0500	[thread overview]
Message-ID: <200908111029.42368.rob0@gmx.co.uk> (raw)
In-Reply-To: <1f4ef0970908110722i41e934bcm48b2ba0d66587dcf@mail.gmail.com>

On Tuesday 11 August 2009 09:22:17 Steve Brown wrote:
> > I always *NAT in PREROUTING and MASQUERADE in POSTROUTING if
> > needed. 
>
> According to the manpage for iptables, SNAT is only valid in the
> POSTROUTING chain.  Is this incorrect?

MASQUERADE is a form of SNAT (source NAT). SNAT is done in the
POSTROUTING chain.

> > Have never seen any such performance drop on multiple NIC.
>
> Neither have I, which is why this is bothering me.

I can't really comment on this. You might consider doing some
troubleshooting to test your hypothesis, such as tcpdump(1) of some
poor-performing connections. You haven't posted anything here which
lends credence to it.

On Monday 10 August 2009 16:43:14 you wrote:
> I'm running a custom 2.6.30.3 kernel.

Do the same symptoms manifest when you're running the distro kernel?
The custom kernel would be a possible suspect.
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  reply	other threads:[~2009-08-11 15:29 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-08-10 21:43 Poor upload speed with NAT Steve Brown
2009-08-10 23:43 ` Amos Jeffries
2009-08-11 14:22   ` Steve Brown
2009-08-11 15:29     ` /dev/rob0 [this message]
2009-08-11 15:58       ` Steve Brown
2009-08-12 14:02 ` Steve Brown
     [not found]   ` <4A82D82F.1000003@shorwall.net>
2009-08-12 16:03     ` Steve Brown
2009-08-12 16:03   ` Tom Eastep

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