Firewall configuration with Red Hat Enterprise Linux 7

You must complete some firewall configuration steps to enable the iptables service on a Red Hat Enterprise Linux® (RHEL) 7 instance.

The RHEL 7 image available with IBM® Cloud Pak System W3550 uses the iptables service when it configures the firewall for a deployed instance. The image disabled the firewalld service and enabled the iptables and ip6tables services instead.

The IBM Spectrum Scale external tiebreaker binary files are using the same scripts that are used by the Cloud Pak System IBM Spectrum Scale Pattern instances, which are deployed on Cloud Pak System. As a result, when the external tiebreaker is installed on a virtual machine that is using RHEL 7, the virtual machine must also enable the iptables service and disable the firewalld service before the external tiebreaker installation scripts are run. This is necessary because the external tiebreaker scripts are using the iptables service to set up the firewall.

The following commands are used by Cloud Pak System to enable the iptables service on an instance that uses RHEL 7. You can use the same commands, or similar ones, to disable the firewalld service and enable the iptables on the external tiebreaker virtual machine, when that virtual machine is using RHEL 7.
echo "Disable the firewalld service"
systemctl mask firewalld

echo "Activate the iptables and ip6tables services at boot"
systemctl enable iptables
systemctl enable ip6tables

echo "Stop the firewalld service"
systemctl stop firewalld