1、什么是amoeba？
Amoeba(变形虫)项目，专注 分布式数据库 proxy 开发。座落与Client、DB Server(s)之间。对客户端透明。具有负载均衡、高可用性、sql过滤、读写分离、可路由相关的query到目标数据库、可并发请求多台数据库合并结果。
主要解决：
• 降低 数据切分带来的复杂多数据库结构
• 提供切分规则并降低 数据切分规则 给应用带来的影响
• 降低db 与客户端的连接数
• 读写分离
2、为什么要用Amoeba
目前要实现mysql的主从读写分离，主要有以下几种方案：
1、 通过程序实现，网上很多现成的代码，比较复杂，如果添加从服务器要更改多台服务器的代码。
2、 通过mysql-proxy来实现，由于mysql-proxy的主从读写分离是通过lua脚本来实现，目前lua的脚本的开发跟不上节奏，而写没有完美的现成的脚本，因此导致用于生产环境的话风险比较大，据网上很多人说mysql-proxy的性能不高。
3、 自己开发接口实现，这种方案门槛高，开发成本高，不是一般的小公司能承担得起。
4、 利用阿里巴巴的开源项目Amoeba来实现，具有负载均衡、高可用性、sql过滤、读写分离、可路由相关的query到目标数据库，并且安装配置非常简单。国产的开源软件，应该支持，目前正在使用，不发表太多结论，一切等测试完再发表结论吧，哈哈！
3、amoeba安装
1、首先安装jdk，直接使用rpm包安装即可
2、下载amoeba对应的版本https://sourceforge.net/projects/amoeba/，直接解压即可
3、配置amoeba的配置文件
dbServers.xml
<?xml version="1.0" encoding="gbk"?> <!DOCTYPE amoeba:dbServers SYSTEM "dbserver.dtd"> <amoeba:dbServers xmlns:amoeba="http://amoeba.meidusa.com/"> <!-- Each dbServer needs to be configured into a Pool, If you need to configure multiple dbServer with load balancing that can be simplified by the following configu ration: add attribute with name virtual = "true" in dbServer, but the configuration does not allow the element with n ame factoryConfig such as 'multiPool' dbServer --> <dbServer name="abstractServer" abstractive="true"> <factoryConfig class="com.meidusa.amoeba.mysql.net.MysqlServerConnectionFactory"> <property name="connectionManager">${defaultManager}</property> <property name="sendBufferSize">64</property> <property name="receiveBufferSize">128</property> <!-- mysql port --> <property name="port">3306</property> <!-- mysql schema --> <property name="schema">msb</property> <!-- mysql user --> <property name="user">root</property> <property name="password">123456</property> </factoryConfig> <poolConfig class="com.meidusa.toolkit.common.poolable.PoolableObjectPool"> <property name="maxActive">500</property> <property name="maxIdle">500</property> <property name="minIdle">1</property> <property name="minEvictableIdleTimeMillis">600000</property> <property name="timeBetweenEvictionRunsMillis">600000</property> <property name="testOnBorrow">true</property> <property name="testOnReturn">true</property> <property name="testWhileIdle">true</property> </poolConfig> </dbServer> <dbServer name="writedb" parent="abstractServer"> <factoryConfig> <!-- mysql ip --> <property name="ipAddress">192.168.85.11</property> </factoryConfig> </dbServer> <dbServer name="slave" parent="abstractServer"> <factoryConfig> <!-- mysql ip --> <property name="ipAddress">192.168.85.12</property> </factoryConfig> </dbServer> <dbServer name="myslave" virtual="true"> <poolConfig class="com.meidusa.amoeba.server.MultipleServerPool"> <!-- Load balancing strategy: 1=ROUNDROBIN , 2=WEIGHTBASED , 3=HA--> <property name="loadbalance">1</property> <!-- Separated by commas,such as: server1,server2,server1 --> <property name="poolNames">slave</property> </poolConfig> </dbServer> </amoeba:dbServers>
amoeba.xml
<?xml version="1.0" encoding="gbk"?> <!DOCTYPE amoeba:configuration SYSTEM "amoeba.dtd"> <amoeba:configuration xmlns:amoeba="http://amoeba.meidusa.com/"> <proxy> <!-- service class must implements com.meidusa.amoeba.service.Service --> <service name="Amoeba for Mysql" class="com.meidusa.amoeba.mysql.server.MySQLService"> <!-- port --> <property name="port">8066</property> <!-- bind ipAddress --> <!-- <property name="ipAddress">127.0.0.1</property> --> <property name="connectionFactory"> <bean class="com.meidusa.amoeba.mysql.net.MysqlClientConnectionFactory"> <property name="sendBufferSize">128</property> <property name="receiveBufferSize">64</property> </bean> </property> <property name="authenticateProvider"> <bean class="com.meidusa.amoeba.mysql.server.MysqlClientAuthenticator"> <property name="user">root</property> <property name="password">123456</property> <property name="filter"> <bean class="com.meidusa.toolkit.net.authenticate.server.IPAccessController"> <property name="ipFile">${amoeba.home}/conf/access_list.conf</property> </bean> </property> </bean> </property> </service> <runtime class="com.meidusa.amoeba.mysql.context.MysqlRuntimeContext"> <!-- proxy server client process thread size --> <property name="executeThreadSize">128</property> <!-- per connection cache prepared statement size --> <property name="statementCacheSize">500</property> <!-- default charset --> <property name="serverCharset">utf8</property> <!-- query timeout( default: 60 second , TimeUnit:second) --> <property name="queryTimeout">60</property> </runtime> </proxy> <!-- Each ConnectionManager will start as thread manager responsible for the Connection IO read , Death Detection --> <connectionManagerList> <connectionManager name="defaultManager" class="com.meidusa.toolkit.net.MultiConnectionManagerWrapper"> <property name="subManagerClassName">com.meidusa.toolkit.net.AuthingableConnectionManager</property> </connectionManager> </connectionManagerList> <!-- default using file loader --> <dbServerLoader class="com.meidusa.amoeba.context.DBServerConfigFileLoader"> <property name="configFile">${amoeba.home}/conf/dbServers.xml</property> </dbServerLoader> <queryRouter class="com.meidusa.amoeba.mysql.parser.MysqlQueryRouter"> <property name="ruleLoader"> <bean class="com.meidusa.amoeba.route.TableRuleFileLoader"> <property name="ruleFile">${amoeba.home}/conf/rule.xml</property> <property name="functionFile">${amoeba.home}/conf/ruleFunctionMap.xml</property> </bean> </property> <property name="sqlFunctionFile">${amoeba.home}/conf/functionMap.xml</property> <property name="LRUMapSize">1500</property> <property name="defaultPool">writedb</property> <property name="writePool">writedb</property> <property name="readPool">myslave</property> <property name="needParse">true</property> </queryRouter> </amoeba:configuration>
4、启动amoeba
/root/amoeba-mysql-3.0.5-RC/bin/launcher
4、测试amoeba
--测试的sql --在安装amoeba的服务器上登录mysql mysql -h192.168.85.13 -uroot -p123 -P8066 --分别在master、slave、amoeba上登录mysql use msb select * from user; --在amoeba上插入数据 insert into user values(2,2); --在master和slave上分别查看表中的数据 select * from user; --将master上的mysql服务停止，继续插入数据会发现插入不成功，但是能够查询 --将master上的msyql服务开启，停止slave上的mysql，发现插入成功，但是不能够查询
