How does ubuntu shut down the firewall and ubuntu shut down the firewall?

How does ubuntu shut down the firewall and ubuntu shut down the firewall?

1. disable ubuntu firewall ufw disable
2. uninstalled iptables apt-get remove iptables

1. Use the iptables-F command to disable the firewall. before using this command, you must remember to use iptables.
-L check the default target and iptables of all links in your system.
-F: This command only clears all rules, but does not actually close iptables. Imagine that if the default target of your chain is DROP, you have rules to allow specific ports,
However, once iptables-L is applied and all rules are cleared, the default target will block any access, including remote ssh management server.

So the recommended command to disable the firewall is

Iptables-P INPUT ACCEPT

Iptables-P FORWARD ACCEPT

Iptables-P OUTPUT ACCEPT

Iptables-F


In short, when you want to make any changes on your server, it is best to have a test environment that has been fully tested and then applied to your server. in addition, to use iptables properly, you must understand
The operating principle of iptables is to know how iptables processes each data packet. In this way, rules can be accurately written to avoid unnecessary troubles.