...
Starting namenodes on []
localhost: Error: JAVA_HOME is not set and could not be found.localhost: Error: JAVA_HOME is not set and could not be found.
...
starting yarn daemons
starting resourcemanager, logging to /home/lihanhui/open-source/hadoop-2.1.0-beta/logs/yarn-admin-resourcemanager-localhost.out
localhost: Error: JAVA_HOME is not set and could not be found.
直接命令行执行export JAVA_HOME=/PATH/TO/JDK无法解决问题
grep命令发现libexec/hadoop-config.sh文件中有错误提示中的黑体字，于是在对应位置前直接设置export JAVA_HOME=/PATH/TO/JDK
错误消失。
hadoop版本：hadoop-2.1.0-beta
