java - 我正在org.apache.hadoop.ipc.RemoteException:Mapreduce作业中的java.io.IOException？

Question

我已经使用以下几点安装了hadoop。

使用tar文件

安装hadoop

创建了hdfs用户和组，并将其分配给hadoop文件夹

然后在/ opt文件夹

中为namenode和datanode创建hdfs目录

也设置了配置文件。

但是，当我尝试运行 hadoop jar hadoop-examples-1.0.0.jar pi 4 100 时，出现此错误。

2014-11-05 12:12:02,978 WARN org.apache.hadoop.hdfs.DFSClient: Error Recovery for block null bad datanode[0] nodes == null 
2014-11-05 12:12:02,978 WARN org.apache.hadoop.hdfs.DFSClient: Could not get block locations. Source file "/tmp/hadoop-hdfs/mapred/system/jobtracker.info" - Aborting...
2014-11-05 12:12:02,979 WARN org.apache.hadoop.mapred.JobTracker: Writing to file   hdfs://hostname:9000/tmp/hadoop-hdfs/mapred/system/jobtracker.info failed! 
2014-11-05 12:12:02,979 WARN org.apache.hadoop.mapred.JobTracker: FileSystem is not ready yet!
2014-11-05 12:12:02,982 WARN org.apache.hadoop.mapred.JobTracker: Failed to initialize recovery manager.

org.apache.hadoop.ipc.RemoteException: java.io.IOException: File /tmp/hadoop-hdfs/mapred/system/jobtracker.info could only be replicated to 0 nodes, instead of 1
     at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:1556)
     at org.apache.hadoop.hdfs.server.namenode.NameNode.addBlock(NameNode.java:696)
     at sun.reflect.GeneratedMethodAccessor7.invoke(Unknown Source)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:606)
     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$1.run(Server.java:1384)
     at java.security.AccessController.doPrivileged(Native Method)
     at javax.security.auth.Subject.doAs(Subject.java:415)
     at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1083)
     at org.apache.hadoop.ipc.Server$Handler.run(Server.java:1382)

     at org.apache.hadoop.ipc.Client.call(Client.java:1066)
     at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java:225)
     at com.sun.proxy.$Proxy5.addBlock(Unknown Source)
     at sun.reflect.GeneratedMethodAccessor6.invoke(Unknown Source)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:606)
     at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:82)
     at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:59)
     at com.sun.proxy.$Proxy5.addBlock(Unknown Source)
     at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.locateFollowingBlock(DFSClient.java:3507)
     at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.nextBlockOutputStream(DFSClient.java:3370)
     at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.access$2700(DFSClient.java:2586)
     at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream$DataStreamer.run(DFSClient.java:2826)

我想在此提及的一件事是，我已将hdfs路径设置为/mnt direcotry，但hdfs仍指向/tmp/hadoop-hdfs
请给一些建议。

Answer 1

Check all the paths of the action node you are trying to run,this usually occurs due to wrong input/output paths provided.

Also if you are rerunning a workflow job,make sure all the events and properties provided in coordinator.xml(or job.xml) must be present in job.properties,because rerunning a workflow job doesn't refer to job.xml as against in the case of normal coordinator job run(scheduled running).