参考:http://www.linuxidc.com/Linux/2015-10/124115.htm
一个完整的MySQL读写分离环境包括以下几个部分:
- 应用程序client
- database proxy (Amoeba for MySQL)
- database集群 (M-S)
在本次实战中,应用程序client基于c3p0连接后端的database proxy。database proxy负责管理client实际访问database的路由策略,MySQL Proxy有一项强大功能是实现“读写分离”,基本原理是让主数据库处理写方面事务,让从库处理SELECT查询。Amoeba for MySQL是一款优秀的中间件软件,同样可以实现读写分离,负载均衡等功能,并且稳定性也高于MySQL Proxy,这里采用开源框架Amoeba for MySQL,其使用指南。database集群采用mysql的master-slave的replication方案。整个环境的结构图如下所示:
实战步骤与详解
一.搭建mysql的master-slave环境
1)分别在host1(10.10.148.110)和host2(10.10.148.111)上安装mysql(5.0.45),具体安装方法可见官方文档
2)配置master
首先编辑/etc/my.cnf,添加以下配置:
log-bin=mysql-bin #slave会基于此log-bin来做replication
server-id=1 #master的标示
binlog-do-db = amoeba_study #用于master-slave的具体数据库
3)在Master MySQL上创建一个用户‘repl’,并允许其他Slave服务器可以通过远程访问Master,通过该用户读取二进制日志,实现数据同步
mysql> create user repl; //创建新用户
mysql> GRANT REPLICATION SLAVE ON *.* TO aaa@qq.com IDENTIFIED BY '111111';
附加说明 :
执行 mysql>GRANT REPLICATION SLAVE ON *.* TO 'repl'@'192.168.0.%' IDENTIFIED BY 'mysql';
192.168.0.%,这个配置是指明repl用户所在服务器,这里%是通配符,表示192.168.0.0-192.168.0.255的Server都可以以repl用户登陆主服务器。当然你也可以指定固定Ip。
4)重启mysql,使得配置生效:
/etc/init.d/mysqld restart
最后查看master状态:
5)配置slave
首先编辑/etc/my.cnf,添加以下配置:
server-id=2 #slave的标示
配置生效后,配置与master的连接:
mysql> CHANGE MASTER TO
-> MASTER_HOST='10.10.148.110',
-> MASTER_USER='repl',
-> MASTER_PASSWORD='111111',
-> MASTER_LOG_FILE='mysql-bin.000003',
-> MASTER_LOG_POS=161261;
其中MASTER_HOST是master机的ip,MASTER_USER和MASTER_PASSWORD就是我们刚才在master上添加的用户,MASTER_LOG_FILE和MASTER_LOG_POS对应与master status里的信息
最后启动slave:
mysql> start slave;
6)验证master-slave搭建生效
通过查看slave机的log(/var/log/mysqld.log):
100703 07:31:12 [Note] Slave I/O thread: connected to master 'aaa@qq.com:3306', replication started in log 'mysql-bin.000003' at position 161261
如看到以上信息则证明搭建成功,如果有问题也可通过此log找原因
二.搭建database proxy
此次实战中database proxy采用amoeba ,它的相关信息可以查阅官方文档,不在此详述,下面说说Windows for amoeba的安装及配置
1)安装amoeba
下载1 链接: https://sourceforge.net/projects/amoeba/?source=typ_redirect
or
下载2 amoeba-mysql-binary-2.2.0.tar.gz 后解压到(D:/amoeba-mysql-binary-2.2.0),即完成安装
2)配置amoeba
先配置proxy连接和与各后端mysql服务器连接信息(D:/amoeba-mysql-binary-2.2.0/conf/amoeba.xml):
<server>
<!-- proxy server绑定的端口 -->
<property name="port">8066</property>
<!-- proxy server绑定的IP -->
<!--
<property name="ipAddress">127.0.0.1</property>
-->
<!-- proxy server net IO Read thread size -->
<property name="readThreadPoolSize">20</property>
<!-- proxy server client process thread size -->
<property name="clientSideThreadPoolSize">30</property>
<!-- mysql server data packet process thread size -->
<property name="serverSideThreadPoolSize">30</property>
<!-- socket Send and receive BufferSize(unit:K) -->
<property name="netBufferSize">128</property>
<!-- Enable/disable TCP_NODELAY (disable/enable Nagle's algorithm). -->
<property name="tcpNoDelay">true</property>
<!-- 对外验证的用户名 -->
<property name="user">root</property>
<!-- 对外验证的密码 -->
<property name="password">root</property>
</server>
以上是proxy提供给client的连接配置
<dbServerList>
<dbServer name="server1">
<!-- PoolableObjectFactory实现类 -->
<factoryConfig class="com.meidusa.amoeba.mysql.net.MysqlServerConnectionFactory">
<property name="manager">defaultManager</property>
<!-- 真实mysql数据库端口 -->
<property name="port">3306</property>
<!-- 真实mysql数据库IP -->
<property name="ipAddress">10.10.148.110</property>
<property name="schema">amoeba_study</property>
<!-- 用于登陆mysql的用户名 -->
<property name="user">root</property>
<!-- 用于登陆mysql的密码 -->
<property name="password"></property>
</factoryConfig>
<!-- ObjectPool实现类 -->
<poolConfig class="com.meidusa.amoeba.net.poolable.PoolableObjectPool">
<property name="maxActive">200</property>
<property name="maxIdle">200</property>
<property name="minIdle">10</property>
<property name="minEvictableIdleTimeMillis">600000</property>
<property name="timeBetweenEvictionRunsMillis">600000</property>
<property name="testOnBorrow">true</property>
<property name="testWhileIdle">true</property>
</poolConfig>
</dbServer>
<dbServer name="server2">
<!-- PoolableObjectFactory实现类 -->
<factoryConfig class="com.meidusa.amoeba.mysql.net.MysqlServerConnectionFactory">
<property name="manager">defaultManager</property>
<!-- 真实mysql数据库端口 -->
<property name="port">3306</property>
<!-- 真实mysql数据库IP -->
<property name="ipAddress">10.10.148.111</property>
<property name="schema">amoeba_study</property>
<!-- 用于登陆mysql的用户名 -->
<property name="user">root</property>
<!-- 用于登陆mysql的密码 -->
<property name="password"></property>
</factoryConfig>
<!-- ObjectPool实现类 -->
<poolConfig class="com.meidusa.amoeba.net.poolable.PoolableObjectPool">
<property name="maxActive">200</property>
<property name="maxIdle">200</property>
<property name="minIdle">10</property>
<property name="minEvictableIdleTimeMillis">600000</property>
<property name="timeBetweenEvictionRunsMillis">600000</property>
<property name="testOnBorrow">true</property>
<property name="testWhileIdle">true</property>
</poolConfig>
</dbServer>
</dbServerList>
以上是proxy与后端各mysql数据库服务器配置信息,具体配置见注释很明白了
最后配置读写分离策略:
<queryRouter class="com.meidusa.amoeba.mysql.parser.MysqlQueryRouter">
<property name="LRUMapSize">1500</property>
<property name="defaultPool">server1</property>
<property name="writePool">server1</property>
<property name="readPool">server2</property>
<property name="needParse">true</property>
</queryRouter>
从以上配置不然发现,写操作路由到server1(master),读操作路由到server2(slave)
3)启动amoeba
在命令行里运行D:/amoeba-mysql-binary-2.2.0/amoeba.bat即可:
log4j:WARN log4j config load completed from file:D:/amoeba-mysql-binary-2.2.0/conf/log4j.xml
log4j:WARN ip access config load completed from file:D:/amoeba-mysql-binary-2.2.0/conf/access_list.conf
2010-07-03 09:55:33,821 INFO net.ServerableConnectionManager - Server listening on 0.0.0.0/0.0.0.0:8066.
三.client端调用与测试
1)编写client调用程序
具体程序细节就不详述了,只是一个最普通的基于mysql driver的jdbc的数据库操作程序
2)配置数据库连接
本client基于c3p0,具体数据源配置如下:
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
destroy-method="close">
<property name="driverClass" value="com.mysql.jdbc.Driver" />
<property name="jdbcUrl" value="jdbc:mysql://localhost:8066/amoeba_study" />
<property name="user" value="root" />
<property name="password" value="root" />
<property name="minPoolSize" value="1" />
<property name="maxPoolSize" value="1" />
<property name="maxIdleTime" value="1800" />
<property name="acquireIncrement" value="1" />
<property name="maxStatements" value="0" />
<property name="initialPoolSize" value="1" />
<property name="idleConnectionTestPeriod" value="1800" />
<property name="acquireRetryAttempts" value="6" />
<property name="acquireRetryDelay" value="1000" />
<property name="breakAfterAcquireFailure" value="false" />
<property name="testConnectionOnCheckout" value="true" />
<property name="testConnectionOnCheckin" value="false" />
</bean>
值得注意是,client端只需连到proxy,与实际的数据库没有任何关系,因此jdbcUrl、user、password配置都对应于amoeba暴露出来的配置信息
3)调用与测试
首先插入一条数据:insert into test(id,name) values(10,'test10')
通过查看master机上的日志/var/lib/mysql/mysql_log.log:
1 Query set names latin1
1 Query SET NAMES latin1
1 Query SET character_set_results = NULL
1 Query SHOW VARIABLES
1 Query SHOW COLLATION
1 Query SET autocommit=1
1 Query SET sql_mode='STRICT_TRANS_TABLES'
1 Query SHOW VARIABLES LIKE 'tx_isolation'
1 Query SHOW FULL TABLES FROM `amoeba_study` LIKE 'PROBABLYNOT'
1 Prepare [1] insert into test(id,name) values(?,?)
1 Prepare [2] insert into test(id,name) values(?,?)
1 Execute [2] insert into test(id,name) values(10,'test10')
得知写操作发生在master机上
通过查看slave机上的日志/var/lib/mysql/mysql_log.log:
112313 7:38:12 2 Query insert into test(id,name) values(10,'test10')
得知slave同步执行了这条语句
然后查一条数据:select t.name from test t where t.id = 10
通过查看slave机上的日志/var/lib/mysql/mysql_log.log:
33 Query set names latin1
33 Prepare [1] select t.name from test t where t.id = ?
33 Prepare [2] select t.name from test t where t.id = ?
33 Execute [2] select t.name from test t where t.id = 10
得知读操作发生在slave机上
并且通过查看slave机上的日志/var/lib/mysql/mysql_log.log发现这条语句没在master上执行
通过以上验证得知简单的master-slave搭建和实战得以生效