4.5. Configuring iptables

For Ambari to communicate during setup with the hosts it deploys to and manages, certain ports must be open and available. The easiest way to do this is to temporarily disable iptables.

chkconfig iptables off
/etc/init.d/iptables stop

You can restart iptables after setup is complete.

If the security protocols at your installation do not allow you to disable iptables, you can proceed with them on, as long as all of the relevant ports are open and available. If you plan to run with them enabled, see Configuring Ports (for the 1.x stack) or Configuring Ports (for the 2.x stack) for more information on the necessary ports per component.

During the Ambari Server setup process, Ambari checks to see if iptables is running. If it is, a warning prints to remind you to check that the necessary ports are open and available. The Host Confirm step of the Cluster Install Wizard will also issue a warning for each host that has has iptables running.

	Important
	If you leave iptables enabled and do not set up the necessary ports, the cluster installation will fail.