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by lazyant 2170 days ago
For people asking: you can create a resetfw.sh script, for iptables:

  #!/bin/bash

  iptables -P INPUT ACCEPT  
  iptables -P FORWARD ACCEPT  
  iptables -P OUTPUT ACCEPT  
  iptables -t nat -F  
  iptables -t mangle -F  
  iptables -F  
  iptables -X
chmod +x resetfw.sh

and add it for ex to /etc/cron.hourly directory

This way you can test your iptables rules and they'll get clear at every hour. Once you check they are OK you can delete this cronjob.

(NOTE: I'm typing from memory, haven't tested this)

3 comments

https://manpages.debian.org/stretch/iptables/iptables-apply....

Or use `at` to run `iptables-restore`. Simpler than setting up a cronjob (and if youre doing it manually, cron has a bunch of gotchas that at least bite me in the ass once in a blue moon).

Yes. Although iirc (it may have changed, haven't looked "recently" the iptable- commands are distro specific, as in not all of them have / had them).
You might add a daily task to remove that task just in case you forget. That way you avoid lockout but don't end up opening yourself up accidentally.
Or possibly just turn iptables off, in the same cron.hourly.
Ah yes, that's simpler: systemctl stop iptables. Also need to do systemctl disable iptables just in case, otherwise if the server reboots the iptables service will restart.