hadoop-集群启动问题1：datanode未启动：

1.问题点

：

2020-05-17 20:21:02,927 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /home/hadoop/data/hadoopdata/data/in_use.lock acquired by nodename [email protected]
2020-05-17 20:21:02,930 WARN org.apache.hadoop.hdfs.server.common.Storage: Failed to add storage directory [DISK]file:/home/hadoop/data/hadoopdata/data/
java.io.IOException: Incompatible clusterIDs in /home/hadoop/data/hadoopdata/data: namenode clusterID = CID-e251d99b-a9f7-445f-aefc-f19e5a899c26; datanode clusterID = CID-ad30da33-3399-46f9-8349-a7a9fe1f9ea5

2，解决办法：

先进入目录：cd /home/hadoop/data/hadoopdata/data/current/

并修改目录下的VERSION文件

把原来的clusterID更换成报错的namenode clusterID后面提醒得ID，最后stop-all.sh,再进行start-dfs.sh和start-yarn.sh即可。