[ILUG] iptables and local http

[paul at clubi.ie]

On Sun, 29 Apr 2007, Colin O'Keeffe wrote:

> I;m also running apache on the box , currently port 8080, but i'd 
> like to have it on port 80. So, can iptables detect a http request 
> for the linux box and pass the request to apache and anything that 
> doesnt have an ultimate destination of the linux box be passed 
> through the proxy.?? How do I do it?

# iptables -t nat -v -L  PREROUTING
Chain PREROUTING (policy ACCEPT 85M packets, 6139M bytes)
   pkts bytes target     prot opt in     out     source               destination
    85M 6140M trans-proxy  all  --  any    any     anywhere             anywhere

# iptables -t nat -v -L  trans-proxy
Chain trans-proxy (1 references)
   pkts bytes target     prot opt in     out     source               destination
     10   600 RETURN     tcp  --  any    any     anywhere             <webserver IP>  tcp dpt:http
   275K   14M RETURN     tcp  --  any    any     anywhere             <other webserver IP>  tcp dpt:http
   296K   18M REDIRECT   tcp  --  eth0   any     anywhere             anywhere            tcp dpt:http redir ports 8080

> -A PREROUTING -i eth0 -p tcp -m tcp --dport 80 -j REDIRECT --to-ports 3128

You need to add 'exceptions' where packets are destined to port 80 on 
your webserver, e.g. as above.

regards,
-- 
Paul Jakma	paul at clubi.ie	paul at jakma.org	Key ID: 64A2FF6A
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