Question : I set up my firewall/packet filtering but after a reboot the rules are not there any more. Solution: By default, rules created with the iptables command are stored in memory. If the system is restarted before saving the iptables rule set, all rules will be lost. For netfilter rules to persist through system reboot, they need to be saved. To do this, log in as root and type: # service iptables save This executes the iptables init script, which runs the iptables-save program … [Read more...] about CentOS / RHEL 6 : How to Save iptables Rules