How Ubuntu shuts down the firewall

1. Turn off Ubuntu's firewall UFW disable
2. Uninstalled the iptables         apt-get remove iptables



-F This command simply clears all the rules and does not really shut down the iptables. Imagine if your chain default target is drop, you have rules to allow some specific ports,
But once the iptables-l is applied and all rules are cleared, the default target will block any access, including, of course, the remote SSH Management Server.













Iptables's operating principle, knowing how each packet iptables is handled. This allows you to write rules accurately and avoid unnecessary hassles.

How Ubuntu shuts down the firewall