Hadoop疑难问题

Q1：Spark出现解决Retrying connect to server: 0.0.0.0/0.0.0.0:8031. Already tried 0 time(s);
解决方案
修改yarn-site.xml，添加下面内容

    <property>
        <name>yarn.resourcemanager.address</name>
        <value>muhe221:8032</value>
    </property>
    <property>
        <name>yarn.resourcemanager.scheduler.address</name>
        <value>muhe221:8030</value>
    </property>
    <property>
        <name>yarn.resourcemanager.resource-tracker.address</name>
        <value>muhe221:8031</value>
    </property>

 

Q2：hadoop-2.7.7执行hadoop wordcount用例报错
Could not find or load main class org.apache.hadoop.mapreduce.v2.app.MRAppMaster

解决办法：修改mapred-site.xml

   /home/hadoop/soft/hadoop-2.7.7/etc/hadoop,
   /home/hadoop/soft/hadoop-2.7.7/share/hadoop/common/*,
   /home/hadoop/soft/hadoop-2.7.7/share/hadoop/common/lib/*,
   /home/hadoop/soft/hadoop-2.7.7/share/hadoop/hdfs/*,
   /home/hadoop/soft/hadoop-2.7.7/share/hadoop/hdfs/lib/*,
   /home/hadoop/soft/hadoop-2.7.7/share/hadoop/mapreduce/*,
   /home/hadoop/soft/hadoop-2.7.7/share/hadoop/mapreduce/lib/*,
   /home/hadoop/soft/hadoop-2.7.7/share/hadoop/yarn/*,
   /home/hadoop/soft/hadoop-2.7.7/share/hadoop/yarn/lib/*