Question

我是Hadoop的初学者，我尝试使用MR将一些数据导入HBase但失败了。控制台显示错误信息：

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

我通过google和stackoverflow找到了一些解决方案，大多数解决方案都表示它与mapred-site.xml和yarn-site.xml的配置有关，但是，我发现我没有错。 mapreduce.application.classpath有问题吗？

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>

纱-site.xml中

<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

类路径应该用冒号（:)而不是逗号（，）分隔，将mapreduce.application.classpath和yarn.application.classpath修改为/usr/local/hadoop/etc/hadoop:/usr/local/hadoop/share/hadoop/common/*:...，看看是否能解决问题。< / p>

无法启动MapReduce任务。无法找到或加载主类org.apache.hadoop.mapreduce.v2.app.MRAppMaster

1 个答案: