hadoop.security.authentication kerberos dfs.nameservices phdcluster dfs.ha.namenodes.phdcluster nn1,nn2 dfs.namenode.rpc-address.phdcluster.nn1 mdw:8020 dfs.namenode.rpc-address.phdcluster.nn2 smdw:8020 dfs.client.failover.proxy.provider.phdcluster org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider