hdfs dfs -ls /user
hdfs dfs -fs hdfs://nn1 -ls /user
hdfs dfs -put test.txt /user/hdfs
hdfs dfs -rm /user/hdfs/test.txt
hdfs dfs -rm -r /user/hdfs/test/
hdfs dfs -du /user
hdfs dfs -setrep 2 /user/hdfs/test.txt
hdfs dfs -setrep -R 2 /user/hdfs
hdfs fsck / -blocks
hdfs dfsadmin -report
hdfs dfsadmin -setBalancerBandwidth 1073741824
hdfs dfsadmin -safemode get
hdfs dfsadmin -safemode enter
hdfs dfsadmin -safemode leave
hdfs dfsadmin -saveNamespace
hdfs haadmin -getServiceState nn1
hdfs haadmin -failover nn1 nn2