If Windows Firewall is in use on the cluster nodes, this wizard automatically enables Windows Firewall rules needed on each ...

If Windows Firewall is in use on the cluster nodes, this wizard automatically enables Windows Firewall rules needed on each node to allow remote restarts during an Updating Run. This is required for CAU to update this failover cluster. If you use a non-Microsoft firewall, configure an exception manually before the first Updating Run. For more information, see the {0} in the Windows Server TechNet Library.