1.修改配置文件

<!-- 开启日志聚集功能 -->

<property>

    <name>yarn.log-aggregation-enable</name>

    <value>true</value>

</property>

<!-- 设置日志聚集服务器地址 -->

<property>  

    <name>yarn.log.server.url</name>  

    <value>http://hadoop101:19888/jobhistory/logs</value>

</property>

<!-- 设置日志保留时间为7天 -->

<property>

    <name>yarn.log-aggregation.retain-seconds</name>

    <value>604800</value>

</property>

2.分发配置文件

xsync /opt/module/hadoop-3.1.3/etc/hadoop

3.重新启动服务

重启yarn

start-yarn.sh

mapred --daemon start historyserver

4.重新运行

hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-3.1.3.jar wordcount /wcinput /output1

查看日志