ERROR: User defined in HDFS_DATANODE_SECURE_USER (yarn) does not exist. Aborting.

错误

在4台服务器上安装高可用的Hadoop时，启动DataNode一直报下列的错误：
在Google了半天，也没有找到原因真的是抓耳挠撒
下面是启动时的报错。

[root@node01 hadoop]# start-all.sh 
Starting namenodes on [node01 node02]
Starting datanodes
node02: ERROR: User defined in HDFS_DATANODE_SECURE_USER (yarn) does not exist. Aborting.
node03: ERROR: User defined in HDFS_DATANODE_SECURE_USER (yarn) does not exist. Aborting.
node04: ERROR: User defined in HDFS_DATANODE_SECURE_USER (yarn) does not exist. Aborting.
Starting journal nodes [node01 node02 node03]
2019-04-26 15:14:39,251 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Starting ZK Failover Controllers on NN hosts [node01 node02]
Starting resourcemanagers on [ node03 node04]
node04: WARNING: /opt/hadoop-3.1.2/logs does not exist. Creating.
Starting nodemanagers

解决方法：

1. 将hadoop-env.sh里面的角色分配全部给注释掉

   #JAVA
   export JAVA_HOME=/usr/java/jdk1.8.0_201-amd64
   # HDFS
   # export HDFS_NAMENODE_USER=root
   # export HDFS_DATANODE_USER=root
   # export HDFS_SECONDARYNAMENODE_USER=root
   # export HDFS_ZKFC_USER=root
   # export HDFS_JOURNALNODE_USER=root
   # export HADOOP_SECURE_DN_USER=hdfs
   # export HDFS_DATANODE_SECURE_USER=hdfs
   
   #YARN
   #export YARN_RESOURCEMANAGER_USER=root
   # export HADOOP_SECURE_DN_USER=yarn 
   #export HDFS_DATANODE_SECURE_USER=yarn
   #export YARN_NODEMANAGER_USER=root
   
   

2. 在start-dfs.sh, stop-dfs.sh中添加入如下的内容

   #!/usr/bin/env bash
   
   HDFS_DATANODE_USER=root
   HDFS_DATANODE_SECURE_USER=hdfs
   HDFS_NAMENODE_USER=root
   HDFS_SECONDARYNAMENODE_USER=root
   
   # Licensed to the Apache Software Foundation (ASF) under one or more
   # contributor license agreements.  See the NOTICE file distributed with
   # this work for additional information regarding copyright ownership.
   # The ASF licenses this file to You under the Apache License, Version 2.0
   ...........
   

3. 在start-yarn.sh, stop-yarn.sh中添加如下内容

   #!/usr/bin/env bash
   
   YARN_RESOURCEMANAGER_USER=root
   HDFS_DATANODE_SECURE_USER=yarn
   YARN_NODEMANAGER_USER=root
   
   # Licensed to the Apache Software Foundation (ASF) under one or more
   # contributor license agreements.  See the NOTICE file distributed with
   # this work for additional information regarding copyright ownership.
   # The ASF licenses this file to You under the Apache License, Version 2.0
   ............