From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Opperisano Subject: Re: Help: iptables NAT broken with pppoe Date: Mon, 9 May 2005 10:08:51 -0400 Message-ID: <20050509140851.GA4840@bender.817west.com> References: <1115397393l.3864l.0l@antares.localdomain> <427C5C41.3010407@riverviewtech.net> <1115496014l.3549l.0l@antares.localdomain> <427EFB7D.8010503@riverviewtech.net> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <427EFB7D.8010503@riverviewtech.net> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: netfilter-bounces@lists.netfilter.org Errors-To: netfilter-bounces@lists.netfilter.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: netfilter@lists.netfilter.org On Mon, May 09, 2005 at 12:56:13AM -0500, Taylor, Grant wrote: > Ok. I've never heard or seen reference to /proc/sys/net/ipv4/ip_dynaddr > before and I'm not sure what its purpose is let alone that it is requried. > Does any one have any more information on what it is and what its purpose > is? ************************************************************************ $ cat /usr/src/linux-2.6.11/Documentation/networking/ip_dynaddr.txt IP dynamic address hack-port v0.03 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This stuff allows diald ONESHOT connections to get established by dynamically changing packet source address (and socket's if local procs). It is implemented for TCP diald-box connections(1) and IP_MASQuerading(2). 1) Socket (and packet) source address is rewritten ON RETRANSMISSIONS while in SYN_SENT state (diald-box processes). 2) Out-bounded MASQueraded source address changes ON OUTPUT (when internal host does retransmission) until a packet from outside is received by the tunnel. This is specially helpful for auto dialup links (diald), where the ``actual'' outgoing address is unknown at the moment the link is going up. So, the *same* (local AND masqueraded) connections requests that bring the link up will be able to get established. [*] At boot, by default no address rewriting is attempted. To enable: # echo 1 > /proc/sys/net/ipv4/ip_dynaddr To enable verbose mode: # echo 2 > /proc/sys/net/ipv4/ip_dynaddr To disable (default) # echo 0 > /proc/sys/net/ipv4/ip_dynaddr Enjoy! -- Juanjo ************************************************************************ -j -- "Narrator: Remember, nothing says "good job" like a firm, open-palm slap on the behind." --Family Guy