I add this rule:

sudo iptables -t nat -A OUTPUT -d a.b.c.d -p tcp \
       --dport 1723 -j DNAT --to-destination a.b.c.d:10000
  1. When restart computer rules are deleted. Why?
  2. What I can do to make the rules persist?

There is no option in iptables which will make your rules permanent. But you can use iptables-save and iptables-restore to fulfill your task.

First add the iptable rule using the command you gave.

Then save iptables rules to some file like /etc/iptables.conf using following command:

$  iptables-save > /etc/iptables.conf

Add the following command in /etc/rc.local to reload the rules in every reboot.

$  iptables-restore < /etc/iptables.conf
  • 20
    On Debian there is the iptables-persistent package which will do this. – bahamat Oct 20 '12 at 0:09
  • 10
    It's rather bad idea to place it in rc.local since there would be an open window gap between services start and firewall policy apply. I do prefer using pre-up hook for loopback interface in /etc/network/interfaces to overcome this. – poige Oct 20 '12 at 11:07
  • @poige: I agree 100%, rc.local might have the intended effect, but it's a kludge in this situation. – J. M. Becker Oct 20 '12 at 14:52
  • 3
    @bahamat: Installing that package is the best solution, It deserves it's own answer. – J. M. Becker Oct 20 '12 at 14:54
  • 1
    @TechZilla: Done. – bahamat Oct 22 '12 at 1:52

(Because it was suggested to make this an answer of its own...)

On Debian, install iptables-persistent:

sudo apt-get install iptables-persistent

The package will automatically load /etc/iptables/rules for you during boot.

Any time you modify your rules, run /sbin/iptables-save > /etc/iptables/rules to save them. You can also add that to the shutdown sequence if you like.

  • 18
    There are two different rule files: /etc/iptables/rules.v4 and /etc/iptables/rules.v6 for IPv4 and IPv6 respectively. If you want a table to apply to both kinds of connections you have to save it to both rule files. – PetaspeedBeaver Jan 23 '14 at 15:51
  • 15
    Don't add it to your shutdown sequence! If you botch your rules during changes/setup at least a good old reboot will get things back to the previously working state. – VertigoRay Feb 27 '17 at 23:03

After installing iptables-persistent above you can also save rules with the following shorter command on Ubuntu 16.04+: sudo netfilter-persistent save

And they can also be restored back to how they were last time you saved them with: sudo netfilter-persistent reload


Because you did not save the iptables rules.

You can do that by using sudo iptables-save

  • That command only shows the rules on the console. – PhoneixS Sep 29 '20 at 16:34

First install the persist iptables (ubunut or debian)

   apt install iptables-persistent

Run your statement:

   iptables -A INPUT -s 0/0 -p tcp --dport 5433 -j ACCEPT

Then save the settings


Finally restart the machine to verify

  • Did not work for me – trzczy Apr 2 at 11:35

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.