hiveHA

hive—high Avaliable
hive的搭建方式有三种，分别是
1、Local/Embedded Metastore Database (Derby)
2、Remote Metastore Database
3、Remote Metastore Server
一般情况下，我们在学习的时候直接使用hive –service metastore的方式启动服务端，使用hive的方式直接访问登录客户端，除了这种方式之外，hive提供了hiveserver2的服务端启动方式，提供了beeline和jdbc的支持，并且官网也提出，一般在生产环境中，使用hiveserver2的方式比较多，如图：

使用hiveserver2的优点如下：
1、在应用端不需要部署hadoop和hive的客户端
2、hiveserver2不用直接将hdfs和metastore暴露给用户
3、有HA机制，解决应用段的并发和负载问题
4、jdbc的连接方式，可以使用任务语言，方便与应用进行数据交互
本文档主要介绍如何进行hive的HA的搭建：
如何进行搭建，参照之前hadoop的HA，使用zookeeper完成HA

:

2、node1—hive-site.xml
<property>
<name>hive.metastore.warehouse.dir</name>
<value>/user/hive/warehouse</value>
</property>
<property>
<name>javax.jdo.option.ConnectionURL</name>
<value>jdbc:mysql://node1:3306/hive?createDatabaseIfNotExist=true</value>
</property>
<property>
<name>javax.jdo.option.ConnectionDriverName</name>
<value>com.mysql.jdbc.Driver</value>
</property>
<property>
<name>javax.jdo.option.ConnectionUserName</name>
<value>root</value>
</property>
<property>
<name>javax.jdo.option.ConnectionPassword</name>
<value>123</value>
</property>
<property>
<name>hive.server2.support.dynamic.service.discovery</name>
<value>true</value>
</property>
<property>
<name>hive.server2.zookeeper.namespace</name>
<value>hiveserver2_zk</value>
</property>
<property>
<name>hive.zookeeper.quorum</name>
<value>node1:2181,node2:2181,node3:2181</value>
</property>
<property>
<name>hive.zookeeper.client.port</name>
<value>2181</value>
</property>
<property>
<name>hive.server2.thrift.bind.host</name>
<value>node2</value>
</property>
<property>
<name>hive.server2.thrift.port</name>
<value>10001</value>
</property>
3、node4—hive-site.xml
<property>
<name>hive.metastore.warehouse.dir</name>
<value>/user/hive/warehouse</value>
</property>
<property>
<name>javax.jdo.option.ConnectionURL</name>
<value>jdbc:mysql://node1:3306/hive?createDatabaseIfNotExist=true</value>
</property>
<property>
<name>javax.jdo.option.ConnectionDriverName</name>
<value>com.mysql.jdbc.Driver</value>
</property>
<property>
<name>javax.jdo.option.ConnectionUserName</name>
<value>root</value>
</property>
<property>
<name>javax.jdo.option.ConnectionPassword</name>
<value>123</value>
</property>
<property>
<name>hive.server2.support.dynamic.service.discovery</name>
<value>true</value>
</property>
<property>
<name>hive.server2.zookeeper.namespace</name>
<value>hiveserver2_zk</value>
</property>
<property>
<name>hive.zookeeper.quorum</name>
<value>node1:2181,node2:2181,node3:2181</value>
</property>
<property>
<name>hive.zookeeper.client.port</name>
<value>2181</value>
</property>
<property>
<name>hive.server2.thrift.bind.host</name>
<value>node4</value>
</property>
<property>
<name>hive.server2.thrift.port</name>
<value>10001</value>
</property>
4、使用jdbc或者beeline两种方式进行访问
1） beeline
!connect jdbc:hive2://node1,node2,node3/;serviceDiscoveryMode=zooKeeper;zooKeeperNamespace=hiveserver2_zk root 123
2）jdbc
public class HiveJdbcClient2 {

private static String driverName = "org.apache.hive.jdbc.HiveDriver";

public static void main(String[] args) throws SQLException {
try {
Class.forName(driverName);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}

Connection conn = DriverManager.getConnection("jdbc:hive2://node1,node2,node3/default;serviceDiscoveryMode=zooKeeper;zooKeeperNamespace=hiveserver2_zk", "root", "");
Statement stmt = conn.createStatement();
String sql = "select * from tbl";
ResultSet res = stmt.executeQuery(sql);
while (res.next()) {
System.out.println(res.getString(1));
}
}
}