You must temporarily 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