By default Centos 7 comes with firewallD installed, which is a wrapper around iptables. That’s great for people who don’t understand iptables, but its as cryptic or even worse as iptables so why bother ? On a minimal install, there is no firewalld, iptables is there but is missing iptables-service package. This is a short howto to get iptables up & running, in either minimal or full install.
on a minimal its not there (hence it will fail) but be sure to check it :
# systemctl disable firewalld Failed to execute operation: Access denied
if it is :
systemctl disable firewalld Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service. Removed symlink /etc/systemd/system/basic.target.wants/firewalld.service.
This installs iptables-services and will make it possible to “save” it again. (I also set it to start after reboot)
yum install iptables-services systemctl enable iptables
and voila :
service iptables save service ip6tables save
ready to firewall up!