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From: Pascal Hambourg <pascal.mail@plouf.fr.eu.org>
To: netfilter@vger.kernel.org
Subject: Re: SNAT problem
Date: Sun, 22 Aug 2010 23:12:06 +0200	[thread overview]
Message-ID: <4C7192A6.90109@plouf.fr.eu.org> (raw)
In-Reply-To: <4C716DF6.3040602@pisem.net>

Yevgeny Kosarzhevsky a écrit :
> 
> I have two interfaces, let's say ppp0 - x.x.x.x, ppp1 - y.y.y.y ppp0 is 
> a default gateway.
> I use some command to change routing to IP z.z.z.z via ppp1:
> ip ro ad to z.z.z.z dev ppp1
> 
> I have SNAT rules for both interfaces, however, I notice with tcpdump 
> that outgoing packets are still using x.x.x.x instead of y.y.y.y IP, 
> though packets are being sent with the correct interface (ppp1)
> 
> I have shut down ppp0 and removed SNAT rule for it, but outgoing packets 
> are still showing x.x.x.x IP. Even, ip ro fl cache didn't help.

If the packets belong to an existing connection (conntrack-wise) which
was established before the route change, this behaviour is expected.
Changing the source address may break the connection.

  reply	other threads:[~2010-08-22 21:12 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-08-22 18:35 SNAT problem Yevgeny Kosarzhevsky
2010-08-22 21:12 ` Pascal Hambourg [this message]
     [not found]   ` <4C8C9C9C.2010005@pisem.net>
2010-09-13  9:10     ` Pascal Hambourg
  -- strict thread matches above, loose matches on Subject: below --
2009-07-01 10:00 Manu

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