hadoop 2.0.1 HA配置部署
今天折腾HA，那叫一个顺利啊，
我原本准备花一周时间来折腾的，结果今天一天基本搞定，没遇到什么大问题。
要写总结，我也不知道写啥了。
大致流程罗列一下吧。
主要分三步，
第一步，弄清楚HA原理架构，这个参考官方文档，说的很清楚。
http://hadoop.apache.org/docs/r2.0.0-alpha/hadoop-yarn/hadoop-yarn-site/HDFSHighAvailability.html
http://www.cloudera.com/blog/2012/03/high-availability-for-the-hadoop-distributed-file-system-hdfs/
http://yanbohappy.sinaapp.com/?p=50 （中文的，很不错）
第二步，部署好NFS，这个网上也有很多。
http://blog.sina.com.cn/s/blog_542627730100ipi5.html 我主要参考这个，下面是粘贴
<configuration> <!-- NameNode URI of the cluster --> <property> <name>fs.defaultFS</name> <value>hdfs://hadoopii</value> </property> <property> <name>fs.trash.interval</name> <value>1440</value> </property> </configuration>
<configuration> <property> <name>dfs.federation.nameservices</name> <value>hadoopii</value> </property> <property> <name>dfs.permissions.superusergroup</name> <value>hadoop</value> </property> <!-- namenode dir --> <property> <name>dfs.namenode.name.dir</name> <value>/data/NameNode</value> </property> <!-- datanode dir --> <property> <name>dfs.datanode.data.dir</name> <value>/data/DataNode</value> </property> <property> <name>dfs.replication</name> <value>2</value> </property> <property> <name>dfs.datanode.max.xcievers</name> <value>4096</value> </property> <!-- datanode dir --> <property> <name>dfs.checksum.type</name> <value>CRC32</value> </property> <property> <name>dfs.ha.namenodes.hadoopii</name> <value>nn1,nn2</value> </property> <property> <name>dfs.namenode.rpc-address.hadoopii.nn1</name> <value>myhost20:54310</value> </property> <property> <name>dfs.namenode.rpc-address.hadoopii.nn2</name> <value>myhost-1:54310</value> </property> <property> <name>dfs.namenode.servicerpc-address.hadoopii.nn1</name> <value>myhost20:53310</value> </property> <property> <name>dfs.namenode.servicerpc-address.hadoopii.nn2</name> <value>myhost-1:53310</value> </property> <property> <name>dfs.namenode.http-address.hadoopii.nn1</name> <value>myhost20:50070</value> </property> <property> <name>dfs.namenode.http-address.hadoopii.nn2</name> <value>myhost-1:50070</value> </property> <property> <name>dfs.client.failover.proxy.provider.hadoopii</name> <value>org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider</value> </property> <property> <name>dfs.namenode.shared.edits.dir</name> <value>file:///nfs_myhost0/hdfs/ha-name-dir-shared</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/hdfs/.ssh/id_rsa</value> </property> <property> <name>dfs.ha.fencing.ssh.connect-timeout</name> <value>5000</value> </property></configuration>