retry.RetryInvocationHandler (RetryInvocationHandler.java:invoke(140))

报错信息如下

2017-12-20 12:29:09,161 INFO  [main]: retry.RetryInvocationHandler (RetryInvocationHandler.java:invoke(140)) 
- Exception while invoking getFileInfo of class ClientNamenodeProtocolTranslatorPB over bdata236/192.168.1.236:9000 
after 3 fail over attempts. Trying to fail over after sleeping for 5584ms.
org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.ipc.StandbyException): Operation category READ is not supported in state standby
 at org.apache.hadoop.hdfs.server.namenode.ha.StandbyState.checkOperation(StandbyState.java:87)
 at org.apache.hadoop.hdfs.server.namenode.NameNode$NameNodeHAContext.checkOperation(NameNode.java:1719)

• 我出现这个问题的原因是两个namenode都是standby状态，发现是因为zkfc没有起来，启动zkfc就OK了。

　　进入hadoop/bin目录下

　./hadoop-daemon.sh start zkfc

• 还有可能是因为防火墙问题,关闭即可

service iptables stop  (centos6)

systemctl stop firewalld(centos7)