Re: iptables with alias?

[leolistas@solucoesip.net]

   I think you'll have to tweak your firewall scripts and build your own 
customized SNAT rules. I mean ..... your firewall script can easily get 
the IP address of the interface ( even alias one ) with something similar 
to:

ifconfig "eth0 " | grep inet | cut -d":" -f 2 | cut -d" " -f 1


   Then, in POSTROUTING you could build your rules, just like:

iptables -t nat -A POSTROUTING -s 192.168.1.5 -j SNAT --to-source $IP_ETH0
iptables -t nat -A POSTROUTING -s 192.168.1.6 -j SNAT --to-source 
$IP_ETH00
iptables -t nat -A POSTROUTING -s 192.168.1.8/29 -j SNAT --to-source 
$IP_ETH01 ( 192.168.1.8/29 matches 7-15 )
... and go on ....

   Note that this script can be only executed after ALL interfaces get 
their IP addresses ....


   Hope this helps,
   Leonardo Rodrigues


Quoting Jeppe Sørensen <smed@tdcadsl.dk>:

> Hello
> 
> I have a little question that perhaps someone can help me with
> 
> I have a interface to the inet with 4 dynamic ip addr
> eth0 = first dynamic ip addr
> eth0:0 = second dynmaic ip addr
> and so on
> 
> I want to make 1 on 1 nat on the frist 2 aliass and the last 2 alias are
> for
> the rest of the network
> 192.168.1.5 nat to eth0
> 192.168.1.6 nat to eth0:0
> 192.168.1.7-to-15 nat to eth0:1
> 192.168.1.16-to-30 nat to eth0:2
> 
> but iptables wan't take alias
> 
> What do I do / what can I do ?
> 
> I have looked in the The netfilter user mailinglist Archives and found
> the
> following solution
> 
> ip addr add w.x.y.z/bits dev eth0 label eth00
> 
> but how does I get it to work with dynamic address?