高可用MapReduce搭建

高可用MapReduce搭建

hadoop3请使用JDK8，否则会有错误！！！！

修改配置文件：在主节点修改

yarn-site.xml文件配置

<configuration>

<configuration>
    <property>
        <name>yarn.nodemanager.aux-services</name>
        <value>mapreduce_shuffle</value>
    </property>
</configuration>

<property>
  <name>yarn.resourcemanager.ha.enabled</name>
  <value>true</value>
</property>
<property>
  <name>yarn.resourcemanager.cluster-id</name>
  <value>cluster1</value>
</property>
<property>
  <name>yarn.resourcemanager.ha.rm-ids</name>
  <value>rm1,rm2</value>
</property>
<property>
  <name>yarn.resourcemanager.hostname.rm1</name>
  <value>node03</value>
</property>
<property>
  <name>yarn.resourcemanager.hostname.rm2</name>
  <value>node04</value>
</property>
<property>
  <name>yarn.resourcemanager.webapp.address.rm1</name>
  <value>node03:8088</value>
</property>
<property>
  <name>yarn.resourcemanager.webapp.address.rm2</name>
  <value>node04:8088</value>
</property>
<property>
  <name>yarn.resourcemanager.zk-address</name>
  <value>node02:2181,node03:2181,node04:2181</value>
</property>

</configuration>

mapred-site.xml文件配置

<configuration>
    <property>
        <name>mapreduce.framework.name</name>
        <value>yarn</value>
    </property>
<tconfiguration>

配置文件分发

scp yarn-site.xml mapred-site.xml node02:`pwd`
scp yarn-site.xml  mapred-site.xml node03:`pwd`
scp yarn-site.xml mapred-site.xml  node04:`pwd`

datanode：node03,node04节点免密

# node03节点操作
ssh-keygen -t dsa -P '' -f ~/.ssh/id_dsa
cat id_dsa.pub >> authorized_keys
scp id_dsa.pub node04:`pwd`/node03.pub
# node04节点操作
ssh-keygen -t dsa -P '' -f ~/.ssh/id_dsa
cat id_dsa.pub >> authorized_keys
scp id_dsa.pub node04:`pwd`/node04.pub
cat node03.pub >> authorized_key
# node03节点操作
cat node04.pub >> authorized_key

启动集群

# 所有节点
zkServer.sh start
# 主节点
start-dfs.sh
# 3,4节点
yarn --daemon start resourcemanager

使用jdk12会出现错误，需要换回JDK8！

可能错误：

1. /bin/bash: /bin/java: No such file or directory：删掉/bin/java这一个文件，然后生成软连接ln -s /usr/java/jdk1.8.0_221/bin/java /bin/java

2. Could not find or load main class org.apache.hadoop.mapreduce.v2.app.MRAppMaster，按提示修改：

Please check whether your etc/hadoop/mapred-site.xml contains the below configuration:
<property>
  <name>yarn.app.mapreduce.am.env</name>
  <value>HADOOP_MAPRED_HOME=${full path of your hadoop distribution directory}</value>
</property>
<property>
  <name>mapreduce.map.env</name>
  <value>HADOOP_MAPRED_HOME=${full path of your hadoop distribution directory}</value>
</property>
<property>
  <name>mapreduce.reduce.env</name>
  <value>HADOOP_MAPRED_HOME=${full path of your hadoop distribution directory}</value>
</property>