HDFS-6507. Improve DFSAdmin to support HA cluster better. (Contributd by Zesheng Wu) ........ git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1604695 13f79535-47bb-0310-9956-ffa450edef68
HDFS-6507. Improve DFSAdmin to support HA cluster better. (Contributd by Zesheng Wu) ........ git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1604695 13f79535-47bb-0310-9956-ffa450edef68