MapReduce运行异常：Unknown protocol to name node: org.apache.hadoop.mapred.JobSubmissionProtocol

MapReduce运行异常：Unknown protocol to name node: org.apache.hadoop.mapred.JobSubmissionProtocol

描述：job 配置错误

异常：

14/03/26 22:23:27 ERROR security.UserGroupInformation: PriviledgedActionException as:allen cause:org.apache.hadoop.ipc.RemoteException: java.io.IOException: Unknown protocol to name node: org.apache.hadoop.mapred.JobSubmissionProtocol at org.apache.hadoop.hdfs.server.namenode.NameNode.getProtocolVersion(NameNode.java:149) at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:563) at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1388) at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1384) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:396) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1121) at org.apache.hadoop.ipc.Server$Handler.run(Server.java:1382)
Exception in thread "main" org.apache.hadoop.ipc.RemoteException: java.io.IOException: Unknown protocol to name node: org.apache.hadoop.mapred.JobSubmissionProtocol at org.apache.hadoop.hdfs.server.namenode.NameNode.getProtocolVersion(NameNode.java:149) at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:563) at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1388) at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1384) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:396) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1121) at org.apache.hadoop.ipc.Server$Handler.run(Server.java:1382)

解决办法：

conf.set("mapred.job.tracker", "ip:端口");

端口和地址在：mapred-site.xml中

 <property>
                <name>mapred.job.tracker</name>
                <value>ip:端口</value>
        </property>

如果还无法解决：

注释掉conf.set("mapred.job.tracker", "ip:端口");

然后配置输入输出目录时，配上hdfs的路径

String[] ioArgs = new String[] { "hdfs://ip:端口/mr/sort/sort_in", "hdfs://ip:端口/mr/sort/sort_out" };