**修改mapred-site.xml,配置使用yarn框架执行mapreduce处理程序,与之前版本多了后面两部**
**不配置mapreduce.application.classpath这个参数mapreduce运行时会报错:**
**Error: Could not find or load main class org.apache.hadoop.mapreduce.v2.app.MRAppMaster**
<configuration>
<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>
<property>
<name>mapreduce.application.classpath</name>
<value>
/data/soft/hadoop-3.2.0/etc/hadoop,
/data/soft/hadoop-3.2.0/share/hadoop/common/*,
/data/soft/hadoop-3.2.0/share/hadoop/common/lib/*,
/data/soft/hadoop-3.2.0/share/hadoop/hdfs/*,
/data/soft/hadoop-3.2.0/share/hadoop/hdfs/lib/*,
/data/soft/hadoop-3.2.0/share/hadoop/mapreduce/*,
/data/soft/hadoop-3.2.0/share/hadoop/mapreduce/lib/*,
/data/soft/hadoop-3.2.0/share/hadoop/yarn/*,
/data/soft/hadoop-3.2.0/share/hadoop/yarn/lib/*
</value>
</property>
</configuration>
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