[dip@dip003 ~]$ hadoop distcp -update /user/hive/warehouse/tmp.db/ hdfs://172.26.xx.xx:8020/user/hive/warehouse/tmp.db/
18/12/24 10:27:06 ERROR tools.DistCp: Invalid arguments:
org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.ipc.StandbyException): Operation category READ is not supported in state standby. Visit https://s.apache.org/sbnn-error
原因：
目标集群的节点是namenode 的standby节点，更换为active节点即可。