ERROR: JAVA_HOME is not set and could not be found.

背景

1. 启动hadoop集群时报错,先是报错Attempting to operate on hdfs namenode as root but there is no HDFS_NAMENODE_USER defined. Aborting

解决方案

1. 在$HADOOP_HOME/etc/hadoop目录下添加jdk的位置,注意分发到集群其它机器

   export JAVA_HOME=/opt/module/jdk1.8