4.6. Disable SELinux and PackageKit and check the umask Value

You must disable SELinux for the Ambari setup to function. On each host in your cluster,

setenforce 0

	Note
	To permanently disable SELinux set SELINUX=disabled in /etc/selinux/config This ensures that SELinux does not turn itself on after you reboot the machine .

On an installation host running RHEL/CentOS with PackageKit installed, open /etc/yum/pluginconf.d/refresh-packagekit.conf using a text editor. Make the following change:

enabled=0

	Note
	PackageKit is not enabled by default on SLES or Ubuntu systems. Unless you have specifically enabled PackageKit, you may skip this step for a SLES or Ubuntu installation host.

UMASK (User Mask or User file creation MASK) sets the default permissions or base permissions granted when a new file or folder is created on a Linux machine. Most Linux distros set 022 as the default umask value. A umask value of 022 grants read, write, execute permissions of 755 for new files or folders. A umask value of 027 grants read, write, execute permissions of 750 for new files or folders. Ambari supports a umask value of 022 or 027. For example, to set the umask value to 022, run the following command as root on all hosts, vi /etc/profile then, append the following line: umask 022