CentOS 7 Firewall Configuration

Solution 1:

Since the release of RedHat/CentOS 7, the previous firewall system has been replaced with firewalld.

At the time of writing there is no curses-like console interface similar to system-config-firewall. If you don't mind using a GUI you could use firewall-config instead.

If you need something for the console you will have to use firewall-cmd instead.

For more information and full documentation about firewalld: 4.5. Using Firewalls

I hope this might help you!

Solution 2:

Here are some commands with descriptions below that I came across and were helpful

firewall-cmd --state
  view status of firewalld service (systemctl status firewalld)
firewall-cmd --zone=public --list-all
  gets all info for the “public” zone
firewall-cmd --list-all-zones
  shows all info for all zones
firewall-cmd --zone=public --add-port=80/tcp --permanent
  adds port 80 to public zone
firewall-cmd --zone=public --add-service=http --permanent
  adds service http to public zone
firewall-cmd --reload
  run this after making changes
firewall-cmd --zone=public --remove-port=80/tcp --permanent
  to remove port 80 from public zone
firewall-cmd --get-default-zone
  shows default zone for firewall
firewall-cmd --get-active-zones
  zones where network interfaces or sources are assigned