(新)尚硅谷大数据技术之Hadoop(入门)第4章 Hadoop运行模式
4.2.2 启动YARN并运行MapReduce程序
- 1. 分析
(1)配置集群在YARN上运行MR
(2)启动、测试集群增、删、查
(3)在YARN上执行WordCount案例
- 2. 执行步骤
(1)配置集群
(a)配置yarn-env.sh
配置一下JAVA_HOME
export JAVA_HOME=/opt/module/jdk1.8.0_144
(b)配置yarn-site.xml
<!-- Reducer获取数据的方式 -->
<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>
<!-- 指定YARN的ResourceManager的地址 -->
<property>
<name>yarn.resourcemanager.hostname</name>
<value>hadoop101</value>
</property>
(c)配置:mapred-env.sh
配置一下JAVA_HOME
export JAVA_HOME=/opt/module/jdk1.8.0_144
(d)配置: (对mapred-site.xml.template重新命名为) mapred-site.xml
[atguigu@hadoop101 hadoop]$ mv mapred-site.xml.template mapred-site.xml
[atguigu@hadoop101 hadoop]$ vi mapred-site.xml
<!-- 指定MR运行在YARN上 -->
<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>
(2)启动集群
(a)启动前必须保证NameNode和DataNode已经启动
(b)启动ResourceManager
[atguigu@hadoop101 hadoop-2.7.2]$ sbin/yarn-daemon.sh start resourcemanager
(c)启动NodeManager
[atguigu@hadoop101 hadoop-2.7.2]$ sbin/yarn-daemon.sh start nodemanager
(3)集群操作
(a)YARN的浏览器页面查看,如图2-35所示
http://hadoop101:8088/cluster
图2-35 YARN的浏览器页面
(b)删除文件系统上的output文件
[atguigu@hadoop101 hadoop-2.7.2]$ bin/hdfs dfs -rm -R /user/atguigu/output
(c)执行MapReduce程序
[atguigu@hadoop101 hadoop-2.7.2]$ bin/hadoop jar
share/hadoop/mapreduce/hadoop-mapreduce-examples-2.7.2.jar wordcount /user/atguigu/input /user/atguigu/output
(d)查看运行结果,如图2-36所示
[atguigu@hadoop101 hadoop-2.7.2]$ bin/hdfs dfs -cat /user/atguigu/output/*