iptables configuration under ubuntu

Posted by aioobe on Server Fault See other posts from Server Fault or by aioobe
Published on 2010-05-11T20:21:59Z Indexed on 2010/05/11 20:25 UTC
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iptables

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ubuntu

I'm following a tutorial on setting up a dns-tunnel.

I've run into the following instruction:

Now you need to enable forwarding on this server. I use iptables to implement masquerading. There are many HOWTOs about this (a simple one, for example). On Debian, the configuration file for iptables is in /var/lib/iptables/active. The relevant bit is:

*nat
:PREROUTING ACCEPT [6:1596]
:POSTROUTING ACCEPT [1:76]
:OUTPUT ACCEPT [1:76]

-A POSTROUTING -s 10.0.0.0/8 -j MASQUERADE
COMMIT

Restart iptables:

/etc/init.d/iptables restart

The problem is that I don't have any /var/lib/iptables/active. (I'm on ubuntu.)

How can I accomplish this? I suspect that I should just interact with the iptables command somehow but I have no clue what to write. Best would probably be if I could put the commands in a script somehow I suppose.

(A side-note. If I execute a few iptables-commands it wont be there for ever, right? The rules will be discarded on reboot?)

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