IPTables

IPTables is the Linux firewall.

Disabling iptables

Red Hat

service iptables save
service iptables stop
chkconfig iptables off

SuSE

service SuSEfirewall2_init stop
service SuSEfirewall2_setup stop
chkconfig SuSEfirewall2_init off
chkconfig SuSEfirewall2_setup off

reboot

Generic

Works on any Linux machine, but the firewall will restore on reboot.

iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
iptables -P FORWARD ACCEPT
iptables -F
iptables -X
iptables -t nat -F
iptables -t nat -X
iptables -t mangle -F
iptables -t mangle -X