FM / html

/usr/share/doc/iptables/html

Name	Size	Mode	Actions
NAT-HOWTO-1.html	1152	0644	edit dl rm
NAT-HOWTO-2.html	4346	0644	edit dl rm
NAT-HOWTO-3.html	1444	0644	edit dl rm
NAT-HOWTO-4.html	4400	0644	edit dl rm
NAT-HOWTO-5.html	5139	0644	edit dl rm
NAT-HOWTO-6.html	8397	0644	edit dl rm
NAT-HOWTO-7.html	1324	0644	edit dl rm
NAT-HOWTO-8.html	1136	0644	edit dl rm
NAT-HOWTO-9.html	2091	0644	edit dl rm
NAT-HOWTO-10.html	2525	0644	edit dl rm
NAT-HOWTO-11.html	910	0644	edit dl rm
NAT-HOWTO.html	2666	0644	edit dl rm
netfilter-extensions-HOWTO-1.html	2102	0644	edit dl rm
netfilter-extensions-HOWTO-2.html	7807	0644	edit dl rm
netfilter-extensions-HOWTO-3.html	28969	0644	edit dl rm
netfilter-extensions-HOWTO-4.html	12548	0644	edit dl rm
netfilter-extensions-HOWTO-5.html	7041	0644	edit dl rm
netfilter-extensions-HOWTO-6.html	11242	0644	edit dl rm
netfilter-extensions-HOWTO-7.html	2188	0644	edit dl rm
netfilter-extensions-HOWTO-8.html	1021	0644	edit dl rm
netfilter-extensions-HOWTO-9.html	2222	0644	edit dl rm
netfilter-extensions-HOWTO.html	7267	0644	edit dl rm
netfilter-hacking-HOWTO-1.html	7474	0644	edit dl rm
netfilter-hacking-HOWTO-2.html	1718	0644	edit dl rm
netfilter-hacking-HOWTO-3.html	8038	0644	edit dl rm
netfilter-hacking-HOWTO-4.html	53338	0644	edit dl rm
netfilter-hacking-HOWTO-5.html	1056	0644	edit dl rm
netfilter-hacking-HOWTO-6.html	3028	0644	edit dl rm
netfilter-hacking-HOWTO-7.html	9288	0644	edit dl rm
netfilter-hacking-HOWTO-8.html	5234	0644	edit dl rm
netfilter-hacking-HOWTO-9.html	835	0644	edit dl rm
netfilter-hacking-HOWTO.html	3811	0644	edit dl rm
packet-filtering-HOWTO-1.html	1891	0644	edit dl rm
packet-filtering-HOWTO-2.html	1593	0644	edit dl rm
packet-filtering-HOWTO-3.html	5775	0644	edit dl rm
packet-filtering-HOWTO-4.html	2189	0644	edit dl rm
packet-filtering-HOWTO-5.html	1644	0644	edit dl rm
packet-filtering-HOWTO-6.html	3505	0644	edit dl rm
packet-filtering-HOWTO-7.html	35616	0644	edit dl rm
packet-filtering-HOWTO-8.html	1457	0644	edit dl rm
packet-filtering-HOWTO-9.html	2333	0644	edit dl rm
packet-filtering-HOWTO-10.html	2575	0644	edit dl rm
packet-filtering-HOWTO-11.html	3742	0644	edit dl rm
packet-filtering-HOWTO.html	2831	0644	edit dl rm

Edit: /usr/share/doc/iptables/html/NAT-HOWTO-9.html (2091B)

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<HTML>
<HEAD>
 <META NAME="GENERATOR" CONTENT="LinuxDoc-Tools 0.9.82">
 <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
 <TITLE>Linux 2.4 NAT HOWTO: Source NAT and Routing</TITLE>
 <LINK HREF="NAT-HOWTO-10.html" REL=next>
 <LINK HREF="NAT-HOWTO-8.html" REL=previous>
 <LINK HREF="NAT-HOWTO.html#toc9" REL=contents>
</HEAD>
<BODY>
<A HREF="NAT-HOWTO-10.html">Next</A>
<A HREF="NAT-HOWTO-8.html">Previous</A>
<A HREF="NAT-HOWTO.html#toc9">Contents</A>
<HR>
<H2><A NAME="s9">9.</A> <A HREF="NAT-HOWTO.html#toc9">Source NAT and Routing</A></H2>

<P>If you are doing SNAT, you will want to make sure that every
machine the SNAT'ed packets goes to will send replies back to the NAT
box.  For example, if you are mapping some outgoing packets onto the
source address 1.2.3.4, then the outside router must know that it is
to send reply packets (which will have <B>destination</B> 1.2.3.4)
back to this box.  This can be done in the following ways:</P>
<P>
<OL>
<LI> If you are doing SNAT onto the box's own address (for which
routing and everything already works), you don't need to do
anything.
</LI>
<LI> If you are doing SNAT onto an unused address on the local LAN
(for example, you're mapping onto 1.2.3.99, a free IP on your
1.2.3.0/24 network), your NAT box will need to respond to ARP
requests for that address as well as its own: the easiest way
to do this is create an IP alias, e.g.:
<BLOCKQUOTE><CODE>
<PRE>
# ip address add 1.2.3.99 dev eth0
</PRE>
</CODE></BLOCKQUOTE>

</LI>
<LI> If you are doing SNAT onto a completely different address, you
will have to ensure that the machines the SNAT packets will hit
will route this address back to the NAT box.  This is already
achieved if the NAT box is their default gateway, otherwise you
will need to advertise a route (if running a routing protocol)
or manually add routes to each machine involved.</LI>
</OL>
</P>

<HR>
<A HREF="NAT-HOWTO-10.html">Next</A>
<A HREF="NAT-HOWTO-8.html">Previous</A>
<A HREF="NAT-HOWTO.html#toc9">Contents</A>
</BODY>
</HTML>

cmd: