三台主机：
192.168.143.111 hdp1
192.168.143.112 hdp2
192.168.143.113 hdp3
1、安装配置ZooKeeper；
(1)在conf目录下创建配置文件zoo.cfg
tickTime=2000
dataDir=.../zookeeper/data
dataLogDir=.../zookeeper/dataLog
clientPort=2181
initLimit=5
syncLimit=2
server.1=hdp1:2888:3888
server.2=hdp2:2888:3888
server.3=hdp3:2888:3888
(2)在ZooKeeper目录下创建myid，hdp1的内容为1，hdp2的内容为2，hdp3的内容为3。
(3)分别启动ZooKeeper：zkServer.sh start
2、修改hadoop配置文件；
core-site.xml
<configuration>
<!-- 指定hdfs的nameservice为ns1 -->
<property>
<name>fs.defaultFS</name>
<value>hdfs://ns1/</value>
</property>
<!-- 指定hadoop临时目录 -->
<property>
<name>hadoop.tmp.dir</name>
<value>/home/hadoop/app/hadoop-2.4.1/tmp</value>
</property>
<!-- 指定zookeeper地址 -->
<property>
<name>ha.zookeeper.quorum</name>
<value>hdp1:2181,hdp2:2181,hdp3:2181</value>
</property>
</configuration>
hdfs-site.xml
<configuration>
<!--指定hdfs的nameservice为ns1，需要和core-site.xml中的保持一致 -->
<property>
<name>dfs.nameservices</name>
<value>ns1</value>
</property>
<!-- ns1下面有两个NameNode，分别是nn1，nn2 -->
<property>
<name>dfs.ha.namenodes.ns1</name>
<value>nn1,nn2</value>
</property>
<!-- nn1的RPC通信地址 -->
<property>
<name>dfs.namenode.rpc-address.ns1.nn1</name>
<value>hdp1:9000</value>
</property>
<!-- nn1的http通信地址 -->
<property>
<name>dfs.namenode.http-address.ns1.nn1</name>
<value>hdp1:50070</value>
</property>
<!-- nn2的RPC通信地址 -->
<property>
<name>dfs.namenode.rpc-address.ns1.nn2</name>
<value>hdp2:9000</value>
</property>
<!-- nn2的http通信地址 -->
<property>
<name>dfs.namenode.http-address.ns1.nn2</name>
<value>hdp2:50070</value>
</property>
<!-- 指定NameNode的元数据在JournalNode上的存放位置，与ZooKeeper位置相同 -->
<property>
<name>dfs.namenode.shared.edits.dir</name>
<value>qjournal://hdp1:8485;hdp2:8485;hdp3:8485/ns1</value>
</property>
<!-- 指定JournalNode在本地磁盘存放数据的位置 -->
<property>
<name>dfs.journalnode.edits.dir</name>
<value>/home/hadoop/app/hadoop-2.4.1/journaldata</value>
</property>
<!-- 开启NameNode失败自动切换 -->
<property>
<name>dfs.ha.automatic-failover.enabled</name>
<value>true</value>
</property>
<!-- 配置失败自动切换实现方式 -->
<property>
<name>dfs.client.failover.proxy.provider.ns1</name>
<value>org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider</value>
</property>
<!-- 配置隔离机制方法，多个机制用换行分割，即每个机制暂用一行-->
<property>
<name>dfs.ha.fencing.methods</name>
<value>
sshfence
shell(/bin/true)
</value>
</property>
<!-- 使用sshfence隔离机制时需要ssh免登陆 -->
<property>
<name>dfs.ha.fencing.ssh.private-key-files</name>
<value>/home/hadoop/.ssh/id_rsa</value>
</property>
<!-- 配置sshfence隔离机制超时时间 -->
<property>
<name>dfs.ha.fencing.ssh.connect-timeout</name>
<value>30000</value>
</property>
</configuration>
yarn-site.xml
<configuration>
<!-- 开启RM高可用 -->
<property>
<name>yarn.resourcemanager.ha.enabled</name>
<value>true</value>
</property>
<!-- 指定RM的cluster id -->
<property>
<name>yarn.resourcemanager.cluster-id</name>
<value>yrc</value>
</property>
<!-- 指定RM的名字 -->
<property>
<name>yarn.resourcemanager.ha.rm-ids</name>
<value>rm1,rm2</value>
</property>
<!-- 分别指定RM的地址 -->
<property>
<name>yarn.resourcemanager.hostname.rm1</name>
<value>hdp1</value>
</property>
<property>
<name>yarn.resourcemanager.hostname.rm2</name>
<value>hdp2</value>
</property>
<!-- 指定zk集群地址 -->
<property>
<name>yarn.resourcemanager.zk-address</name>
<value>hdp1:2181,hdp2:2181,hdp3:2181</value>
</property>
<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>
</configuration>
slaves
hdp3
3、初次启动顺序
先启动ZooKeeper集群：zkServer.sh start
再启动journalnode：hadoop-daemon.sh start journalnode
hdp1上格式化HDFS：hdfs namenode -format
启动hdp1的NameNode：hadoop-daemon.sh start namenode
在hdp2上执行命令：hdfs namenode -bootstrapStandby
在hdp1上执行：hdfs zkfc -formatZK
在hdp1上执行：start-dfs.sh
在hdp1上执行：start-yarn.sh
4、平常启动顺序
先启动ZooKeeper集群
在hdp1上执行：start-dfs.sh start-yarn.sh
在hdp2上执行：yarn-daemon.sh start resourcemanager
5、HA机制下hdfs的Java编程
public class HDFS_HA {public static void main(String[] args) throws Exception {Configuration conf = new Configuration();conf.set("fs.defaultFS", "hdfs://ns1");conf.set("dfs.nameservices", "ns1");conf.set("dfs.ha.namenodes.ns1", "nn1,nn2");conf.set("dfs.namenode.rpc-address.ns1.nn1", "hdp11:9000");conf.set("dfs.namenode.rpc-address.ns1.nn2", "hdp2:9000");//conf.setBoolean(name, value);conf.set("dfs.client.failover.proxy.provider.ns1", "org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider");FileSystem fs = FileSystem.get(new URI("hdfs://ns1"), conf, "hadoop");InputStream in =new FileInputStream("c://eclipse.rar");OutputStream out = fs.create(new Path("/eclipse"));IOUtils.copyBytes(in, out, 4096, true);}
}
 错误)
