Change Linux root user password of Cloudera Hadoop nodes

Cloudera Manager only uses the root credentials when adding a new node to the cluster. Once the node has been added and the Cloudera Manager agent deployed the server will no longer use the root credentials.

i.e.  Once your cluster is set up, you can safely change the root password. Cloudera Manager does not save SSH credentials and all credential information is discarded once the installation is complete.

Changing the root password will not affect any currently deployed services. Nodes talk to each other o SSH key based authentication 

sh-4.2# passwd root
New password: 
Retype new password:
passwd:all authentication tokens updated successfully.