To enable port 80 and Port 3306 for a firewall in Linux

The firewall rule file is in:
/Etc/sysconfig/iptables

Open the configuration file through vi

Add two lines to the table:

-A input-m state-state NEW-m tcp-p tcp-dport 80-j ACCEPT
-A input-m state-state NEW-m tcp-p tcp-dport 3306-j ACCEPT
The result is as follows:

Ou. Restart the firewall now:

Service iptables restart

Attach several firewall commands:

Service iptables status # view the status of iptables
Service iptables restart # restart the iptables service
Service iptables stop # Disable iptables service