centos7中hadoop集群中namenode名字节点挂掉重新恢复的方法
在名字节点master节点上重新执行下面命令：
zkServer.sh start
hadoop-daemon.sh start namenode
hadoop-daemon.sh start datanode
hadoop-daemon.sh start journalnode
hadoop-daemon.sh start zkfc
显示master主机进程结果为:
[hadoop3@master ~]$ looknamenodestate.sh
standby
active
standby
[hadoop3@master ~]$
master,slave1,slave2中slave1为活动名字节点namenode
[hadoop3@master ~]$ runRemoteCmd.sh "jps" all
*******************master***************************
4932 DFSZKFailoverController
2229 NameNode
5125 Jps
2106 QuorumPeerMain
2331 DataNode
2926 JournalNode
*******************slave1***************************
3361 DataNode
3444 JournalNode
5796 Jps
2297 QuorumPeerMain
3531 DFSZKFailoverController
3277 NameNode
*******************slave2***************************
3584 DFSZKFailoverController
5473 Jps
3330 NameNode
3414 DataNode
3497 JournalNode
2315 QuorumPeerMain
*******************datanode1***************************
3345 Jps
2679 DataNode
2255 QuorumPeerMain
*******************datanode2***************************
2609 DataNode
2186 QuorumPeerMain
3598 Jps
*******************datanode3***************************
3720 Jps
2987 DataNode
[hadoop3@master ~]$