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From: Amos Jeffries <squid3@treenet.co.nz>
To: "Artūras Šlajus" <x11@arturaz.net>
Cc: netfilter@vger.kernel.org
Subject: Re: Mystics of packet forwarding
Date: Wed, 07 Jan 2009 19:15:28 +1300	[thread overview]
Message-ID: <49644880.8000903@treenet.co.nz> (raw)
In-Reply-To: <4963B3EB.6090806@arturaz.net>

Artūras Šlajus wrote:
> Hello fellow netfilter users,
> 
> I have a strange problem and I think I should blame my ISP for that...
> 
> Recently I lost connectivity to some sites (i.e. digg.com, yahoo). The 
> best part is that I can regain connectivity by clearing out all the 
> rules from iptables.
> 
> So if I have empty chains - I can connect to digg. After I add one rule:
> 
> iptables -t nat -A POSTROUTING -s 192.168.0.0/16 -j MASQUERADE (or SNAT, 
> doesn't make a difference)

I very much doubt it's your ISP. Maybe the

one-sided NAT does not usually work very well. Try adding both the 
symmetrical sides at once:

SNAT on the outbound request packets
   iptables -t nat -A POSTROUTING -s 192.168.0.0/16 -j SNAT ...

MASQUERADE on the inbound reply packets
  iptables -t nat -A PREROUTING -d 192.168.0.0/16 -j MASQUERADE


AYJ

  parent reply	other threads:[~2009-01-07  6:15 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-01-06 19:41 Mystics of packet forwarding Artūras Šlajus
2009-01-06 20:54 ` Billy Crook
2009-01-06 22:20   ` Artūras Šlajus
2009-01-06 22:52   ` Artūras Šlajus
2009-01-07  6:15 ` Amos Jeffries [this message]
2009-01-07  8:00   ` Ivan Petrushev
2009-01-07  8:50     ` Artūras Šlajus
2009-01-07  8:43 ` Artūras Šlajus
2009-01-07  9:28 ` Artūras Šlajus
2009-01-07 10:51   ` Ivan Petrushev
2009-01-07 11:26     ` Roman Fiedler
2009-01-07 13:59   ` Billy Crook
2009-01-07 15:07   ` Mart Frauenlob
2009-01-07 15:52     ` Ivan Petrushev
2009-01-07 22:36       ` Artūras Šlajus
2009-01-08  1:26         ` /dev/rob0

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