hadoop - Datanode 进程未在 Hadoop 中运行

Question

我使用 this tutorial 设置并配置了一个多节点 Hadoop 集群.

当我输入 start-all.sh 命令时，它显示所有进程正确初始化如下:

starting namenode, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-namenode-jawwadtest1.out
jawwadtest1: starting datanode, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-datanode-jawwadtest1.out
jawwadtest2: starting datanode, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-datanode-jawwadtest2.out
jawwadtest1: starting secondarynamenode, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-secondarynamenode-jawwadtest1.out
starting jobtracker, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-jobtracker-jawwadtest1.out
jawwadtest1: starting tasktracker, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-tasktracker-jawwadtest1.out
jawwadtest2: starting tasktracker, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-tasktracker-jawwadtest2.out

但是，当我键入 jps 命令时，我得到以下输出:

31057 NameNode
4001 RunJar
6182 RunJar
31328 SecondaryNameNode
31411 JobTracker
32119 Jps
31560 TaskTracker

如您所见，没有数据节点进程在运行。我尝试配置单节点集群，但遇到了同样的问题。谁知道这里可能出了什么问题？是否有任何配置文件未在教程中提及，或者我可能已经查看过？我是 Hadoop 的新手，有点迷茫，非常感谢任何帮助。

编辑:hadoop-root-datanode-jawwadtest1.log:

STARTUP_MSG:   args = []
STARTUP_MSG:   version = 1.0.3
STARTUP_MSG:   build = https://svn.apache.org/repos/asf/hadoop/common/branches/$
************************************************************/
2012-08-09 23:07:30,717 INFO org.apache.hadoop.metrics2.impl.MetricsConfig: loa$
2012-08-09 23:07:30,734 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapt$
2012-08-09 23:07:30,735 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl:$
2012-08-09 23:07:30,736 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl:$
2012-08-09 23:07:31,018 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapt$
2012-08-09 23:07:31,024 WARN org.apache.hadoop.metrics2.impl.MetricsSystemImpl:$
2012-08-09 23:07:32,366 INFO org.apache.hadoop.ipc.Client: Retrying connect to $
2012-08-09 23:07:37,949 ERROR org.apache.hadoop.hdfs.server.datanode.DataNode: $
        at org.apache.hadoop.hdfs.server.datanode.DataStorage.doTransition(Data$
        at org.apache.hadoop.hdfs.server.datanode.DataStorage.recoverTransition$
        at org.apache.hadoop.hdfs.server.datanode.DataNode.startDataNode(DataNo$
        at org.apache.hadoop.hdfs.server.datanode.DataNode.<init>(DataNode.java$
        at org.apache.hadoop.hdfs.server.datanode.DataNode.makeInstance(DataNod$
        at org.apache.hadoop.hdfs.server.datanode.DataNode.instantiateDataNode($
        at org.apache.hadoop.hdfs.server.datanode.DataNode.createDataNode(DataN$
        at org.apache.hadoop.hdfs.server.datanode.DataNode.secureMain(DataNode.$
        at org.apache.hadoop.hdfs.server.datanode.DataNode.main(DataNode.java:1$

2012-08-09 23:07:37,951 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: S$
/************************************************************
SHUTDOWN_MSG: Shutting down DataNode at jawwadtest1/198.101.220.90
************************************************************/

Answer 1

你需要做这样的事情:

• bin/stop-all.sh(或 2.x 系列中的 stop-dfs.sh 和 stop-yarn.sh )
• rm -Rf/app/tmp/hadoop-your-username/*
• bin/hadoop namenode -format(或 2.x 系列中的 hdfs)

解决方案取自: http://pages.cs.brandeis.edu/~cs147a/lab/hadoop-troubleshooting/ .基本上它包括从头开始重新启动，因此请确保您不会通过格式化 hdfs 丢失数据。