1. Install with the command
yum install firewalld
2. Then enable with the command
systemctl enable firewalld
3. Start the service with the command
systemctl start firewalld
4. To check whether it is running or not, you can use the command
systemctl status firewalld atau firewall-cmd --state
5. After that check, the default zone used with the command
firewall-cmd --get-default-zone dan zone yang aktif dengan perintah firewall-cmd --get-active-zones
6. Then to add ports to open can use the command
firewall-cmd --zone=public --permanent --add-port=8288/tcp
7. After adding the service needs to be restarted with the command
firewall-cmd --reload atau systemctl restart firewalld
8. To check the results of the configuration / rule that has just been added, you can use the command
firewall-cmd --list-all
9. Selanjutnya bisa tes dari luar server dengan perintah telnet ke port server
telnet x.x.x.x port
