From mboxrd@z Thu Jan 1 00:00:00 1970 From: "/dev/rob0" Subject: Re: Poor upload speed with NAT Date: Tue, 11 Aug 2009 10:29:40 -0500 Message-ID: <200908111029.42368.rob0@gmx.co.uk> References: <1f4ef0970908101443i28bf4c1hc6b280d4096fd100@mail.gmail.com> <6808368f3857f867cd0735df99bacdd8@mail.treenet.co.nz> <1f4ef0970908110722i41e934bcm48b2ba0d66587dcf@mail.gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1f4ef0970908110722i41e934bcm48b2ba0d66587dcf@mail.gmail.com> Content-Disposition: inline Sender: netfilter-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: netfilter@vger.kernel.org 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. -- Offlist mail to this address is discarded unless "/dev/rob0" or "not-spam" is in Subject: header