Single user mode requires that you change the default configuration for all log and data directories to ones that are writable by the cloudera-scm user. The root cause for the failure you're seeing is that /dfs/nn cannot be created by the cloudera-scm user.   Please refer to the single user documentation for all the necessary steps to configure your cluster: http://www.cloudera.com/content/cloudera/en/documentation/core/latest/topics/install_singleuser_reqts.html ... View more