前提：hadoop集群安装
在zk的leader上执行 ：bin/hdfs zkfc –formatZK。出现错误：
解决办法：手动敲击上命令。bin/hdfs zkfc -formatZK （可能的问题是复制的空格或者 - 不一样）
错误的内容：
18/07/14 23:14:40 INFO zookeeper.ZooKeeper: Session: 0x264993282950000 closed
18/07/14 23:14:40 WARN ha.ActiveStandbyElector: Ignoring stale result from old client with sessionId 0x264993282950000
18/07/14 23:14:40 INFO zookeeper.ClientCnxn: EventThread shut down
18/07/14 23:14:40 FATAL tools.DFSZKFailoverController: Got a fatal error, exiting now
org.apache.hadoop.HadoopIllegalArgumentException: Bad argument: –formatZK
at org.apache.hadoop.ha.ZKFailoverController.badArg(ZKFailoverController.java:251)
at org.apache.hadoop.ha.ZKFailoverController.doRun(ZKFailoverController.java:214)
at org.apache.hadoop.ha.ZKFailoverController.access$000(ZKFailoverController.java:61)
at org.apache.hadoop.ha.ZKFailoverController$1.run(ZKFailoverController.java:172)
at org.apache.hadoop.ha.ZKFailoverController$1.run(ZKFailoverController.java:168)
at org.apache.hadoop.security.SecurityUtil.doAsLoginUserOrFatal(SecurityUtil.java:415)
at org.apache.hadoop.ha.ZKFailoverController.run(ZKFailoverController.java:168)
at org.apache.hadoop.hdfs.tools.DFSZKFailoverController.main(DFSZKFailoverController.java:181)
