基本集群搭建见这篇博客：hadoop集群搭建笔记
在基本集群搭建上配置下述文件
HA搭建配置：
hdfs-site.xml
<configuration><!-- set the replication of file, needed base on number of datanode -->
<property><name>dfs.replication</name><value>3</value>
</property>
<property><name>dfs.nameservices</name><value>mycluster</value>
</property>
<!-- set namenode -->
<property><name>dfs.ha.namenodes.mycluster</name><value>nn1,nn2</value>
</property>
<!--set address of nn1,nn2 -->
<property><name>dfs.namenode.rpc-address.mycluster.nn1</name><value>chdp11:8020</value>
</property>
<property><name>dfs.namenode.rpc-address.mycluster.nn2</name><value>chdp12:8020</value>
</property>
<property><name>dfs.namenode.http-address.mycluster.nn1</name><value>chdp11:50070</value>
</property>
<property><name>dfs.namenode.http-address.mycluster.nn2</name><value>chdp12:50070</value>
</property>
<property><name>dfs.namenode.shared.edits.dir</name><value>qjournal://chdp11:8485;chdp12:8485;chdp13:8485/mycluster</value>
</property>
<property><name>dfs.client.failover.proxy.provider.mycluster</name><value>org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider</value>
</property><property><name>dfs.ha.fencing.methods</name><value>sshfence</value></property><property><name>dfs.ha.fencing.ssh.private-key-files</name><value>/home/root/.ssh/id_rsa</value></property>
<property><name>dfs.ha.automatic-failover.enabled</name><value>true</value>
</property>
</configuration>
core-site.xml （配置了trash，不需要的直接去掉）
<configuration>
<property><name>fs.defaultFS</name><value>hdfs://mycluster</value>
</property>
<property><name>dfs.journalnode.edits.dir</name><value>/usr/SFT/HA/hadoop-2.7.2/data/jn</value>
</property>
<property><name>ha.zookeeper.quorum</name><value>chdp11:2181,chdp12:2181,chdp13:2181</value>
</property>
<!-- set the directory with produce when running hadoop-->
<property><name>hadoop.tmp.dir</name><value>/usr/SFT/HA/hadoop-2.7.2/data/tmp</value>
</property>
<!-- configuration for trash-->
<property><name>fs.trash.interval</name><value>60</value><description>Number of minutes after which the checkpointgets deleted. If zero, the trash feature is disabled.This option may be configured both on the server and theclient. If trash is disabled server side then the clientside configuration is checked. If trash is enabled on theserver side then the value configured on the server isused and the client configuration value is ignored.</description>
</property>
<property><name>fs.trash.checkpoint.interval</name><value>0</value><description>Number of minutes between trash checkpoints.Should be smaller or equal to fs.trash.interval. If zero,the value is set to the value of fs.trash.interval.Every time the checkpointer runs it creates a new checkpoint out of current and removes checkpoints created more than fs.trash.interval minutes ago.</description>
</property>
<property><name>ha.zookeeper.quorum</name><value>chdp11:2181,chdp12:2181,chdp13:2181</value>
</property>
</configuration>
后续操作（我用的全路径操作）
（1）关闭所有HDFS服务：
/usr/SFT/HA/hadoop-2.7.2/sbin/stop-dfs.sh
（2）启动Zookeeper集群：
/usr/SFT/HA/hadoop-2.7.2/bin/zkServer.sh start
（3）初始化HA在Zookeeper中状态：
/usr/SFT/HA/hadoop-2.7.2/bin/hdfs zkfc -formatZK
（4）启动HDFS服务：
/usr/SFT/HA/hadoop-2.7.2/sbin/start-dfs.sh
（5）在备机上启动namenode
/usr/SFT/HA/hadoop-2.7.2/sbin/hadoop-daemon.sh start namenode
