# diff /etc/sysconfig/iptables /etc/sysconfig/iptables.org
Result:
1c1,2
< # Generated by iptables-save v1.4.7 on Wed Aug 30 00:09:28 2017
---
> # Firewall configuration written by system-config-firewall
> # Manual customization of this file is not recommended.
3,11c4,12
< :INPUT DROP [0:0]
< :FORWARD DROP [0:0]
< :OUTPUT ACCEPT [24:2320]
< -A INPUT -i lo -j ACCEPT
< -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT
< -A INPUT -p tcp -m tcp --dport 53 -j ACCEPT
< -A INPUT -p udp -m udp --dport 53 -j ACCEPT
< -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
< -A INPUT -p tcp -m tcp --dport 443 -j ACCEPT
---
> :INPUT ACCEPT [0:0]
> :FORWARD ACCEPT [0:0]
> :OUTPUT ACCEPT [0:0]
> -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
> -A INPUT -p icmp -j ACCEPT
> -A INPUT -i lo -j ACCEPT
> -A INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT
> -A INPUT -j REJECT --reject-with icmp-host-prohibited
> -A FORWARD -j REJECT --reject-with icmp-host-prohibited
13d13
< # Completed on Wed Aug 30 00:09:28 2017
Reference:
http://programmerbox.com/2013-12-24_vps_construct_procedure_manual/