Folks, I created two machines on SoftLayer's cloud. The machines are Ubuntu 10.4 64 bit, minimal config. I am running into a really strange problem that I have no idea where it is coming from.

The machines seem to have a default. very complex iptables rule set. I flushed the iptables and was able to verify that the machines were reachable. After a few hours, the iptables rules seem to re-appear.

The machine also has UFW installed. Creating a UFW rule to allow port 8080 (used by my application) does not seem to work either.

Any ideas why this might be happening?



  • Did you check your system log files /var/log/messages and /var/log/syslog for any hint? – Khaled Jan 21 '11 at 17:43

Running dpkg-reconfigure ufw will give you a bit more control over it, once you get the package doing exactly what you want you can reload the config running service ufw restart

In Lucid it has been converted to use upstart, which is a pain to manage, don't even get me started... :D

Let me know how it goes and good luck!

  • Hi Lynxman, thanks for your response. But do you know why/how iptables rules are re-appearing automatically even after I flush them – Raj Jan 21 '11 at 17:50
  • Not 100% sure but I think that has to do with the ufw reloading after log rotation, but since I wasn't certain I didn't say anything :) – lynxman Jan 21 '11 at 18:09

AFAIK, ufw is just a 'front-end' to iptables.

Since you're using ufw, that might be the problem.

My suggestion is to ditch ufw altogether and learn using iptables.

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