無法啓動MapReduce任務。無法找到或加載主類org.apache.hadoop.mapreduce.v2.app.MRAppMaster

Question

我是Hadoop的初學者，我嘗試使用MR將一些數據導入HBase，但失敗。控制檯顯示錯誤信息：

Container exited with a non-zero exit code 1. Last 4096 bytes of stderr : 
Error: Could not find or load main class org.apache.hadoop.mapreduce.v2.app.MRAppMaster 

Here is the screenshot of the whole error log page

我通過谷歌和計算器找到了一些解決方案，大部分的解決方案表示，它正在與mapred-site.xml中和紗線-site.xml中的配置，但是，我發現我沒有錯。 mapreduce.application.classpath有問題嗎？

mapred-site.xml中

<configuration> 
     <property> 
       <name>mapreduce.framework.name</name> 
       <value>yarn</value> 
     </property> 
     <property> 
       <name>mapreduce.jobhistory.address</name> 
       <value>master:10020</value> 
     </property> 
     <property> 
       <name>mapreduce.jobhistory.webapp.address</name> 
       <value>master:19888</value> 
     </property> 
     <property> 
       <name>mapreduce.application.classpath</name> 
       <value> 
        /usr/local/hadoop/etc/hadoop, 
        /usr/local/hadoop/share/hadoop/common/*, 
        /usr/local/hadoop/share/hadoop/common/lib/*, 
        /usr/local/hadoop/share/hadoop/hdfs/*, 
        /usr/local/hadoop/share/hadoop/hdfs/lib/*, 
        /usr/local/hadoop/share/hadoop/mapreduce/*, 
        /usr/local/hadoop/share/hadoop/mapreduce/lib/*, 
        /usr/local/hadoop/share/hadoop/yarn/*, 
        /usr/local/hadoop/share/hadoop/yarn/lib/* 
       </value> 
     </property> 
     <property> 
       <name>mapreduce.app-submisson.cross-platform</name>> 
       <value>true</value>> 
      </property>> 
</configuration> 

紗的site.xml

<configuration> 
     <property> 
      <name>yarn.nodemanager.aux-services</name> 
      <value>mapreduce_shuffle</value> 
     </property> 
     <property> 
      <name>yarn.nodemanager.aux-services.mapreduce.shuffle.class</name> 
      <value>org.apache.hadoop.mapred.ShuffleHandler</value> 
     </property> 
     <property> 
      <name>yarn.resourcemanager.address</name> 
      <value>master:8032</value> 
     </property> 
     <property> 
      <name>yarn.resourcemanager.scheduler.address</name> 
      <value>master:8030</value> 
     </property> 
     <property> 
      <name>yarn.resourcemanager.resource-tracker.address</name> 
      <value>master:8031</value> 
     </property> 
     <property> 
      <name>yarn.resourcemanager.admin.address</name> 
      <value>master:8033</value> 
     </property> 
     <property> 
      <name>yarn.resourcemanager.webapp.address</name> 
      <value>master:8088</value> 
     </property> 
     <property> 
      <name>yarn.application.classpath</name> 
      <value> 
       /usr/local/hadoop/etc/hadoop, 
       /usr/local/hadoop/share/hadoop/common/*, 
       /usr/local/hadoop/share/hadoop/common/lib/*, 
       /usr/local/hadoop/share/hadoop/hdfs/*, 
       /usr/local/hadoop/share/hadoop/hdfs/lib/*, 
       /usr/local/hadoop/share/hadoop/mapreduce/*, 
       /usr/local/hadoop/share/hadoop/mapreduce/lib/*, 
       /usr/local/hadoop/share/hadoop/yarn/*, 
       /usr/local/hadoop/share/hadoop/yarn/lib/* 
      </value> 
     </property> 
</configuration> 

Answer 1

類路徑應該由冒號分隔（:)而不是逗號（，），修改mapreduce.application.classpath和yarn.application.classpath像/usr/local/hadoop/etc/hadoop:/usr/local/hadoop/share/hadoop/common/*:...，看看是否可以解決這個問題。