[root@hadoop10 hadoop-3.1.3]# sbin/start-dfs.sh Starting namenodes on [hadoop10] ERROR: Attempting to operate on hdfs namenode as root ERROR: but there is no HDFS_NAMENODE_USER defined. Aborting operation. Starting datanodes ERROR: Attempting to operate on hdfs datanode as root ERROR: but there is no HDFS_DATANODE_USER defined. Aborting operation. Starting secondary namenodes [hadoop12] ERROR: Attempting to operate on hdfs secondarynamenode as root ERROR: but there is no HDFS_SECONDARYNAMENODE_USER defined. Aborting operation.
解决办法：
第一步：在start-dfs.sh，stop-dfs.sh 两个文件中添加
HDFS_DATANODE_USER=root HADOOP_SECURE_DN_USER=hdfs HDFS_NAMENODE_USER=root HDFS_SECONDARYNAMENODE_USER=root HDFS_JOURNALNODE_USER=root HDFS_ZKFC_USER=root
第二步：在start-yarn.sh，stop-yarn.sh两个文件中添加以下参数
YARN_RESOURCEMANAGER_USER=root HADOOP_SECURE_DN_USER=yarn YARN_NODEMANAGER_USER=root
配置完毕！！
重新启动HDFS和YARN，
！！！！！！问题解决！！！！！！！！
