- Joined
- Oct 21, 2010
- Messages
- 340
- Reaction score
- 184
Here is another way to setup your CentOS Firewall via a remote or local server with root access.
Firewall Configuration from a Terminal
In addition to the graphical Security Level Configuration tool, CentOS also includes the command-line firewall configuration tool that enables configuration changes to be made from a terminal window.
To launch, start a terminal session to access the command prompt (right click on the desktop background and select Terminal from the resulting menu) and type the following at the command-line prompt:
system-config-securitylevel
To access this screen use the Tab key to navigate to the Customize button at the bottom of the screen. Once Customize is highlighted, press the Enter or Space key to select it. The Customization screen should appear as follows:
To activate or deactivate an option use the Tab key to navigate to the required option and press the space bar to toggle the selection. Activated options are marked with an asterisk (*).
To specify a specific port, enter the port number and protocol into the Other ports field in the form of port
rotocol. When you have finished making selections tab to the OK button to return to the main screen and tab to OK again to exit . The customization screen also allows trusted interfaces and masquerading to be configured.
Trusted Interfaces
A trusted interface is a network adapter (either physical or software based) on which traffic is known to be coming from a secure network environment. For example, a CentOS system acting as a firewall for an internal network might contain two network adapters, one of which is connected via a gateway or modem to the internet while the other is connected to the secure internal network. In such a situation, the first adapter would be configured as untrusted, since it is exposed to traffic from the outside world. Assuming the internal network is protected by the firewall and other intrusion prevention measures, the second adapter can be considered to be trustworthy.
Enable firewall
Type the following command as the root user to enable firewall.
# service iptables start
# chkconfig iptables on
Check status of Firewall
# service iptables status
Enable your ports that is needed for your server ect 38101 and 38121 - Credits Yamachi
This is how I setup my firewall on my server and it works great.
This is also a great program for your CentOS side.
Credits: techotopia.com & digitalocean.com for guide and images
Firewall Configuration from a Terminal
In addition to the graphical Security Level Configuration tool, CentOS also includes the command-line firewall configuration tool that enables configuration changes to be made from a terminal window.
To launch, start a terminal session to access the command prompt (right click on the desktop background and select Terminal from the resulting menu) and type the following at the command-line prompt:
system-config-securitylevel
To access this screen use the Tab key to navigate to the Customize button at the bottom of the screen. Once Customize is highlighted, press the Enter or Space key to select it. The Customization screen should appear as follows:
To activate or deactivate an option use the Tab key to navigate to the required option and press the space bar to toggle the selection. Activated options are marked with an asterisk (*).
To specify a specific port, enter the port number and protocol into the Other ports field in the form of port
Trusted Interfaces
A trusted interface is a network adapter (either physical or software based) on which traffic is known to be coming from a secure network environment. For example, a CentOS system acting as a firewall for an internal network might contain two network adapters, one of which is connected via a gateway or modem to the internet while the other is connected to the secure internal network. In such a situation, the first adapter would be configured as untrusted, since it is exposed to traffic from the outside world. Assuming the internal network is protected by the firewall and other intrusion prevention measures, the second adapter can be considered to be trustworthy.
Enable firewall
Type the following command as the root user to enable firewall.
# service iptables start
# chkconfig iptables on
Check status of Firewall
# service iptables status
Enable your ports that is needed for your server ect 38101 and 38121 - Credits Yamachi
This is how I setup my firewall on my server and it works great.
This is also a great program for your CentOS side.
To view the content, you need to sign in or register
Credits: techotopia.com & digitalocean.com for guide and images
Last edited:

