Changing the Administrator Account Password
During install and setup, the Cluster Installer wizard automatically creates a default user with "Ambari Admin" privilege. You can change the password for this user (or other Local users in the system) from the Ambari Administration interface. You can change the password for the default admin user to create a unique administrator credential for your system.
To change the password for the default admin account:
Browse to the Users section.
Select the admin user.
Click the Change Password button.
Enter the current admin password and the new password twice.
Click OK to save the new password.