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Date: Fri, 10 Sep 2010 19:55:34 +0700
From: Victor Sudakov <sudakov@sibptus.tomsk.ru>
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Subject: Re: ipfw fwd and ipfw allow
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Nikos Vassiliadis wrote:
> >A packet generated locally 1) should be forwarded by a 'fwd'
> >rule and 2) should create a dynamic 'allow' rule  for returning
> >traffic. Could you please suggest a ruleset for this.
> 
> The fw has the 10.0.0.1 IP address.
> The 10.0.0.100 IP address belongs to another computer running a TCP
> service at 9999.
> 
> The IPFW rules:
> >fw# ipfw list
> >00100 fwd 10.0.0.100 tcp from any to 10.90.10.3 dst-port 9999 keep-state
> >00200 deny ip from any to any
> >65535 allow ip from any to any

It seems that the 'fwd ... keep-state' statement does create a useful
dynamic rule. It contradicts the ipfw(8) man page but works. Thank you
for enlightment.

-- 
Victor Sudakov,  VAS4-RIPE, VAS47-RIPN
sip:sudakov@sibptus.tomsk.ru