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
Turn off firewall on boot:# chkconfig iptables off
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
Turn on firewall on boot:# chkconfig iptables on
Check out related media
See firewall start and stop video tutorial:
A note about other Linux distribution
If you are using other Linux distribution such as Debian / Ubuntu / Suse / Slakcware Linux etc., try the following generic procedure. First, save the current firewall rules, type:# iptables-save > /root/firewall.rules
OR$ sudo iptables-save > /root/firewall.rules
Next, type the following commands (login as the root) as bash prompt:
iptables -F iptables -X iptables -t nat -F iptables -t nat -X iptables -t mangle -F iptables -t mangle -X iptables -P INPUT ACCEPT iptables -P OUTPUT ACCEPT iptables -P FORWARD ACCEPT
Or create a shell script as follows and run it to disable the firewall:
#!/bin/bash # reset.fw - Reset firewall # set x to 0 - No reset # set x to 1 - Reset firewall # --------------------------------------------------------------------------------------------------------------- # Added support for IPV6 Firewall # --------------------------------------------------------------------------------------------------------------- # Written by Vivek Gite <[email protected]> # --------------------------------------------------------------------------------------------------------------- # You can copy / paste / redistribute this script under GPL version 2.0 or above # ============================================================= x=1 # set to true if it is CentOS / RHEL / Fedora box RHEL=false ### no need to edit below ### IPT=/sbin/iptables IPT6=/sbin/ip6tables if [ "$x" == "1" ]; then if [ "$RHEL" == "true" ]; then # reset firewall using redhat script /etc/init.d/iptables stop /etc/init.d/ip6tables stop else # for all other Linux distro use following rules to reset firewall ### reset ipv4 iptales ### $IPT -F $IPT -X $IPT -Z for table in $(</proc/net/ip_tables_names) do $IPT -t $table -F $IPT -t $table -X $IPT -t $table -Z done $IPT -P INPUT ACCEPT $IPT -P OUTPUT ACCEPT $IPT -P FORWARD ACCEPT ### reset ipv6 iptales ### $IPT6 -F $IPT6 -X $IPT6 -Z for table in $(</proc/net/ip6_tables_names) do $IPT6 -t $table -F $IPT6 -t $table -X $IPT6 -t $table -Z done $IPT6 -P INPUT ACCEPT $IPT6 -P OUTPUT ACCEPT $IPT6 -P FORWARD ACCEPT fi else : fi
To restore or turn on firewall type the following command:# iptables-restore < /root/firewall.rules