CentOS #
This OS provides firewalld as default to administrate system firewall. For switch back to classic iptabales, you need to remove firewalld first:
$ yum remove firewalld
$ yum install iptables iptables-services
Now save your current iptables rules:
$ service iptables save
Please remember to enable iptables on autostart:
$ systemctl enable iptables
You can review your saved iptables configuration in /etc/sysconfig/iptables
To stop iptables, just run:
$ service iptables stop
Debian/Ubuntu #
Please install iptables-persistent package:
$ apt-get install iptables-persistent
The package installer will ask you to save current settings, please feel free to save them.
Rules are stored in /etc/iptables/rules.v4 for IPv4 and /etc/iptables/rules.v6 for IPv6.
To save your rules from command line, please type:
$ service netfilter-persistent save
To reload your iptables rules, please type:
$ service netfilter-persistent reload
If you want to stop iptables, please type:
$ service netfilter-persistent stop
