前言

本节内容是关于hadoop集群下yarn服务的高可用搭建，以及其发生故障转移的处理，同样需要依赖zookeeper集群的实现，实现该集群搭建时，我们要预先保证zookeeper集群是启动状态。yarn的高可用同样依赖zookeeper的临时节点及监控，实现服务的故障转移。其ResourceManager的节点任务同样存储于zookeeper集群中，实现数据的共享。

正文

集群规划

YARN高可用
hadoop101 hadoop102 hadoop103
ResourceManager ResourceManager ResourceManager
NodeManager NodeManager NodeManager
Zookeeper Zookeeper Zookeeper

YARN高可用
hadoop101	hadoop102	hadoop103
ResourceManager	ResourceManager	ResourceManager
NodeManager	NodeManager	NodeManager
Zookeeper	Zookeeper	Zookeeper

修改yarn服务配置文件yarn-site.xml

- yarn-site.xml

<?xml version="1.0"?>
<!--
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License. See accompanying LICENSE file.
-->
<configuration>
    <!-- 指定 MR 走 shuffle -->
    <property>
        <name>yarn.nodemanager.aux-services</name>
        <value>mapreduce_shuffle</value>
    </property>
    <!-- 启用 resourcemanager ha -->
    <property>
        <name>yarn.resourcemanager.ha.enabled</name>
        <value>true</value>
    </property>
    <!-- 声明三台 resourcemanager 的地址 -->
    <property>
        <name>yarn.resourcemanager.cluster-id</name>
        <value>cluster-yarn</value>
    </property>
    <!--指定 resourcemanager 的逻辑列表-->
    <property>
        <name>yarn.resourcemanager.ha.rm-ids</name>
        <value>rm1,rm2,rm3</value>
    </property>
    <!-- ========== rm1 的配置 ========== -->
    <!-- 指定 rm1 的主机名 -->
    <property>
        <name>yarn.resourcemanager.hostname.rm1</name>
        <value>hadoop101</value>
    </property>
    <!-- 指定 rm1 的 web 端地址 -->
    <property>
        <name>yarn.resourcemanager.webapp.address.rm1</name>
        <value>hadoop101:8088</value>
    </property>
    <!-- 指定 rm1 的内部通信地址 -->
    <property>
        <name>yarn.resourcemanager.address.rm1</name>
        <value>hadoop101:8032</value>
    </property>
    <!-- 指定 AM 向 rm1 申请资源的地址 -->
    <property>
        <name>yarn.resourcemanager.scheduler.address.rm1</name>
        <value>hadoop101:8030</value>
    </property>
    <!-- 指定供 NM 连接的地址 -->
    <property>
        <name>yarn.resourcemanager.resource-tracker.address.rm1</name>
        <value>hadoop101:8031</value>
    </property>
    <!-- ========== rm2 的配置 ========== -->
    <!-- 指定 rm2 的主机名 -->
    <property>
        <name>yarn.resourcemanager.hostname.rm2</name>
        <value>hadoop102</value>
    </property>
    <property>
        <name>yarn.resourcemanager.webapp.address.rm2</name>
        <value>hadoop102:8088</value>
    </property>
    <property>
        <name>yarn.resourcemanager.address.rm2</name>
        <value>hadoop102:8032</value>
    </property>
    <property>
        <name>yarn.resourcemanager.scheduler.address.rm2</name>
        <value>hadoop102:8030</value>
    </property>
    <property>
        <name>yarn.resourcemanager.resource-tracker.address.rm2</name>
        <value>hadoop102:8031</value>
    </property>
    <!-- ========== rm3 的配置 ========== -->
    <!-- 指定 rm1 的主机名 -->
    <property>
        <name>yarn.resourcemanager.hostname.rm3</name>
        <value>hadoop103</value>
    </property>
    <!-- 指定 rm1 的 web 端地址 -->
    <property>
        <name>yarn.resourcemanager.webapp.address.rm3</name>
        <value>hadoop103:8088</value>
    </property>
    <!-- 指定 rm1 的内部通信地址 -->
    <property>
        <name>yarn.resourcemanager.address.rm3</name>
        <value>hadoop103:8032</value>
    </property>
    <!-- 指定 AM 向 rm1 申请资源的地址 -->
    <property>
        <name>yarn.resourcemanager.scheduler.address.rm3</name>
        <value>hadoop103:8030</value>
    </property>
    <!-- 指定供 NM 连接的地址 -->
    <property>
        <name>yarn.resourcemanager.resource-tracker.address.rm3</name>
        <value>hadoop103:8031</value>
    </property>
    <!-- 指定 zookeeper 集群的地址 -->
    <property>
        <name>yarn.resourcemanager.zk-address</name>
        <value>hadoop101:2181,hadoop102:2181,hadoop103:2181</value>
    </property>
    <!-- 启用自动恢复 -->
    <property>
        <name>yarn.resourcemanager.recovery.enabled</name>
        <value>true</value>
    </property>
    <!-- 指定 resourcemanager 的状态信息存储在 zookeeper 集群 -->
    <property>
        <name>yarn.resourcemanager.store.class</name>
        <value>org.apache.hadoop.yarn.server.resourcemanager.recovery.ZKRMStateStore</value>
    </property>
    <!-- 环境变量的继承 -->
    <property>
        <name>yarn.nodemanager.env-whitelist</name>
        <value>JAVA_HOME,HADOOP_COMMON_HOME,HADOOP_HDFS_HOME,HADOOP_CONF_DIR,CLASSPATH_PREPEND_DISTCACHE,HADOOP_YARN_HOME,HADOOP_MAPRED_HOME</value>
    </property>
</configuration>