hadoop - 在独立模式下执行hadoop示例时，权限被拒绝

Question

我正在尝试在独立模式下运行hadoop。当我尝试执行命令时

bin/hadoop jar hadoop-mapred-examples-0.21.0.jar grep input output

我收到以下错误:

laxmikant@laxmikant-Inspiron-1464:~/Work/hadoop-0.21.0$ bin/hadoop jar hadoop-mapred-  examples-0.21.0.jar grep input output
/home/laxmikant/Work/hadoop-0.21.0/bin/hadoop-config.sh: line 189:     /home/laxmikant/java/jdk1.7.0_04/bin/java: Permission denied
bin/hadoop: line 120: /home/laxmikant/java/jdk1.7.0_04/bin/java: Permission denied
bin/hadoop: line 120: exec: /home/laxmikant/java/jdk1.7.0_04/bin/java: cannot execute:     Permission denied

如何清除错误？

Answer 1

似乎您从中运行hadoop的用户没有特权来运行java。
但是通过查看Java二进制文件所在的路径(/ home / laxmikant / java /)，用户laxmikant或root用户应该可以轻松访问它。因此，如果您尝试以用户laxmikant的身份执行它并仍然收到错误，那么也许没有正确安装Java。还要确保在hadoop的conf / hadoop-env.sh中正确设置了JAVA_HOME。