Linux Firewall changes

Hi, I’m using Debian Lenny and Webmin 3.86 gpl

I’m trying to use Webmin to make changes to my iptables file through the Linux Firewall page.

It correctly identifies the currently running firewall as: /etc/iptables.up.rules

However, if I try and change something as simple as default action, or activate on boot, or add rule, nothing happens when I hit Apply Configuration. It just reloads the page with the information that was already there before. I check the file through the console and it hasn’t been updated. But it does have comments from previous entries from webmin. Is this broken?

The permissions on the file is -rw-r–r-- root root and I’m logged into webmin as root.

What am I doing wrong? I’m sure I’m missing something!

A first step to tackle such issues can be turning on Webmin’s debug logging, in the “Webmin configuration” section. The log might contain information about what went wrong then.