eclipse开发mapreduce程序时出现的问题

1、报HDFS权限不够:org.apache.hadoop.security.AccessControlException: Permission denied:user=ouqiping, access=WRITE, inode="/user/Administrator/DatingRecommender/ratings.dat":root:supergroup:drwxr-xr-x

  解决办法:

  到服务器上修改hadoop的配置文件:conf/hdfs-core.xml, 找到 dfs.permissions 的配置项 , 将value值改为 false

  <property>
  <name>dfs.permissions</name>
  <value>false</value>
  
<description>
  If "true", enable permission checking in HDFS.
  If "false", permission checking is turned off,
  but all other behavior is unchanged.
  Switching from one parameter value to the other does not change the mode,
  owner or group of files or directories.
  </description>
  </property>

2、账户名字不匹配:org.apache.hadoop.security.AccessControlException: Permission denied: user=ouqiping, access=EXECUTE, inode="/tmp/hadoop-yarn/staging/ouqiping/.staging         /job_1458550621743_0001":root:supergroup:drwx------

  解决办法主要有6种:
  (1),更改linux上hadoop集群的名字为ouqiping
  (2),更改hadoop的hdfs所在的目录的权限为hadoop fs -chmod 777 /user/hadoop
  (3),关闭HDFS的权限认证机制,将dfs.permissions修改为False(经测试,无效,仅可以上传和下载)
  (4),更改Windows7的系统用户名为hadoop
  (5),在Win7上的环境变量中加入HADOOP_USER_NAME并配置在linux上对应的用户名即可
  (6),在提交程序里通过代码临时设置指定HADOOP_USER_NAME的名字和linux上的一致

原文地址:https://www.cnblogs.com/julyme/p/5302680.html