How To disable Firewall in Linux through Command Line?

Ans : Edit the file /etc/sysconfig/system-config-securitylevel using vi editor

vi /etc/sysconfig/system-config-securitylevel

Just change --enable to --disable

How To Change Firewall settings in Linux?

Ans : Type system-config-securitylevel this will open the GUI just edit whatever you want. If you want to add some other port like mysql[3306] , sip [5060] use custom button to add other ports.

Howto disable the iptables firewall in Linux?

Q. Quick question: I need to disable firewall in Linux for testing purpose. I’m using CentOS 4.4. How do I disable the firewall in Linux?

A. A Linux firewall is software based firewall that provides protection between your server (workstation) and damaging content on the Internet or network.

It will try to guard your computer against both malicious users and software such as viruses/worms.

Task: Disable / Turn off Linux Firewall (Red hat/CentOS/Fedora Core)

Type the following two commands (you must login as the root user):

# /etc/init.d/iptables save

# /etc/init.d/iptables stop

Task: Enable / Turn on Linux Firewall (Red hat/CentOS/Fedora Core)

Type the following command to turn on iptables firewall:

# /etc/init.d/iptables start

Other Linux distribution

If you are using other Linux distribution such as Debian / Ubuntu / Suse Linux etc, try following generic procedure.

Save firewall rules

# iptables-save > /root/firewall.rules

OR

$ sudo iptables-save > /root/firewall.rules

Now type the following commands (login as root):

# iptables -X

# iptables -t nat -F

# iptables -t nat -X

# iptables -t mangle -F

# iptables -t mangle -X

# iptables -P INPUT ACCEPT

# iptables -P FORWARD ACCEPT

# iptables -P OUTPUT ACCEPT

To restore or turn on firewall type the following command:

# iptables-restore < /root/firewall.rules