Usage: java DFSAdmin
Note: Administrative commands can only be run as the HDFS superuser.
[-report]
[-safemode enter | leave | get | wait]
[-allowSnapshot <snapshotDir>]
[-disallowSnapshot <snapshotDir>]
[-saveNamespace]
[-rollEdits]
[-restoreFailedStorage true|false|check]
[-refreshNodes]
[-finalizeUpgrade]
[-rollingUpgrade [<query|prepare|finalize>]]
[-metasave filename]
[-refreshServiceAcl]
[-refreshUserToGroupsMappings]
[-refreshSuperUserGroupsConfiguration]
[-printTopology]
[-refreshNamenodes datanodehost:port]
[-deleteBlockPool datanode-host:port blockpoolId [force]]
[-setQuota <quota> <dirname>...<dirname>]
[-clrQuota <dirname>...<dirname>]
[-setSpaceQuota <quota> <dirname>...<dirname>]
[-clrSpaceQuota <dirname>...<dirname>]
[-setBalancerBandwidth <bandwidth in bytes per second>]
[-fetchImage <local directory>]
[-shutdownDatanode <datanode_host:ipc_port> [upgrade]]
[-getDatanodeInfo <datanode_host:ipc_port>]
[-help [cmd]]