Namenode启动报错Operation category JOURNAL is not supported in state standby

org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.ipc.StandbyException): Operation category JOURNAL 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$NameNodeHAContext.checkOperation(NameNode.java:1774)  at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkOperation(FSNamesystem.java:1313)  at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.rollEditLog(FSNamesystem.java:5824)  at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.rollEditLog(NameNodeRpcServer.java:1121)  at org.apache.hadoop.hdfs.protocolPB.NamenodeProtocolServerSideTranslatorPB.rollEditLog(NamenodeProtocolServerSideTranslatorPB.java:142)  at org.apache.hadoop.hdfs.protocol.proto.NamenodeProtocolProtos$NamenodeProtocolService$2.callBlockingMethod(NamenodeProtocolProtos.java:12025)  at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:616)  at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:969)  at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2049)  at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2045)  at java.security.AccessController.doPrivileged(Native Method)  at javax.security.auth.Subject.doAs(Subject.java:422)  at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1657)  at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2043)

at org.apache.hadoop.ipc.Client.call(Client.java:1475)  at org.apache.hadoop.ipc.Client.call(Client.java:1412)  at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:229)  at com.sun.proxy.$Proxy15.rollEditLog(Unknown Source)  at org.apache.hadoop.hdfs.protocolPB.NamenodeProtocolTranslatorPB.rollEditLog(NamenodeProtocolTranslatorPB.java:148)  at org.apache.hadoop.hdfs.server.namenode.ha.EditLogTailer.triggerActiveLogRoll(EditLogTailer.java:273)  at org.apache.hadoop.hdfs.server.namenode.ha.EditLogTailer.access$600(EditLogTailer.java:61)  at org.apache.hadoop.hdfs.server.namenode.ha.EditLogTailer$EditLogTailerThread.doWork(EditLogTailer.java:315)  at org.apache.hadoop.hdfs.server.namenode.ha.EditLogTailer$EditLogTailerThread.access$200(EditLogTailer.java:284)  at org.apache.hadoop.hdfs.server.namenode.ha.EditLogTailer$EditLogTailerThread$1.run(EditLogTailer.java:301)  at org.apache.hadoop.security.SecurityUtil.doAsLoginUserOrFatal(SecurityUtil.java:415)  at org.apache.hadoop.hdfs.server.namenode.ha.EditLogTailer$EditLogTailerThread.run(EditLogTailer.java:297)

原因：两个namenode节点均处于standby状态，没有active状态的节点

　解决办法：hdfs haadmin -transitionToActive --forcemanual nn1（想要转换为active状态的namenode的名称，不是主机的名称）