首先说明一下amoeba 跟 MySQL proxy在读写分离的使用上面的区别：
在MySQL proxy 6.0版本 上面如果想要读写分离并且 读集群、写集群 机器比较多情况下，用mysql proxy 需要相当大的工作量，目前mysql proxy没有现成的 lua脚本。mysql proxy根本没有配置文件， lua脚本就是它的全部，当然lua是相当方便的。那么同样这种东西需要编写大量的脚本才能完成一 个复杂的配置。而Amoeba只需要进行相关的配置就可以满足需求。
假设有这样的使用场景，有三个数据库节点分别命名为Master、Slave1、Slave2如下：
Amoeba: Amoeba <192.168.14.129>
Master： Master <192.168.14.131> （可读写）
Slaves：Slave1 <192.168.14.132>、Slave2<192.168.14.133> （2个平等的数据库。只读/负载均衡）
在 主从数据库 的复制的部分， 任然需要使用数据库自己的复制机制。 Amoeba 不提供复制功能。
1. 起动数据库的主从复制功能。
a. 修改配置文件
master.cnf
server-id = 1 #主数据库标志 # 增加 日志文件， 用于验证读写分离
log = /home/mysql/mysql/log/mysql.log
slave1.cnf
server-id = 2 # 增加 日志文件， 用于验证读写分离
log = /home/mysql/mysql/log/mysql.log
slave2.cnf
server-id = 3 # 增加 日志文件， 用于验证读写分离
log = /home/mysql/mysql/log/mysql.log
b. Master 中 创建两个 只读权限 的用户。 用户名均为：repl_user 密码均为：copy 分别开放给 slave1， slave2
mysql> grant replication slave on *.* to repl_user@192.168.14.132 identified by 'copy'; mysql> grant replication slave on *.* to repl_user@192.168.14.133 identified by 'copy';
c. 查看 Master 信息
mysql> show master status;
+------------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000017 | 2009 | | |
+------------------+----------+--------------+------------------+
1 row in set (0.00 sec)
d. Slave1 ，Slave2 中 启动 Master - Slave 复制功能。分别执行以下命令：
mysql> slave stop;
Query OK, 0 rows affected (0.02 sec) mysql> change master to
-> master_host='192.168.14.131',
-> master_user='repl_user',
-> master_password='copy',
-> master_log_file='mysql-bin.000017',
-> master_log_pos=2009;
Query OK, 0 rows affected (0.03 sec) mysql> start slave;
Query OK, 0 rows affected (0.00 sec)
2. Amoeba 读写分离的配置
a. Master ， Slave1 ，Slave2 中开放权限给 Amoeba 访问。在 Master ， Slave1 ， Slave2 中分别执行：
mysql> grant all on test.* to test_user@192.168.14.129 indentified by '';
Amoeba 访问三个数据库的账号密码相同。
b. 修改 Amoeba 的配置文件，配置文件详细说明请查看 官方文档：http://docs.hexnova.com/amoeba/rw-splitting.html
dbServer.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 configuration:
add attribute with name virtual = "true" in dbServer, but the configuration does not allow the element with name factoryConfig
such as 'multiPool' dbServer
--> <!-- 数据库连接配置的公共部分 -->
<dbServer name="abstractServer" abstractive="true">
<factoryConfig class="com.meidusa.amoeba.mysql.net.MysqlServerConnectionFactory">
<property name="manager">${defaultManager}</property>
<property name="sendBufferSize">64</property>
<property name="receiveBufferSize">128</property> <!-- mysql port -->
<property name="port">3306</property> <!-- mysql schema -->
<property name="schema">test</property> <!-- mysql user -->
<property name="user">test_user</property> <!-- mysql password -->
<property name="password">1234</property> </factoryConfig> <poolConfig class="com.meidusa.amoeba.net.poolable.PoolableObjectPool">
<property name="maxActive">500</property>
<property name="maxIdle">500</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> <!-- Master ，Slave1， Slave2 的独立部分，也就只有 IP 了 -->
<dbServer name="master" parent="abstractServer">
<factoryConfig>
<!-- mysql ip -->
<property name="ipAddress">192.168.14.131</property>
</factoryConfig>
</dbServer> <dbServer name="slave1" parent="abstractServer">
<factoryConfig>
<!-- mysql ip -->
<property name="ipAddress">192.168.14.132</property>
</factoryConfig>
</dbServer> <dbServer name="slave2" parent="abstractServer">
<factoryConfig>
<!-- mysql ip -->
<property name="ipAddress">192.168.14.133</property>
</factoryConfig>
</dbServer> <!-- 数据库池，虚拟服务器，实现读取的负载均衡 -->
<dbServer name="slaves" 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">slave1,slave2</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.net.ServerableConnectionManager">
<!-- Amoeba 端口号 -->
<property name="port">8066</property> <!-- bind ipAddress -->
<!--
<property name="ipAddress">127.0.0.1</property>
--> <property name="manager">${clientConnectioneManager}</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="authenticator">
<bean class="com.meidusa.amoeba.mysql.server.MysqlClientAuthenticator">
<!-- Amoeba 账号，密码 -->
<property name="user">root</property> <property name="password">root</property> <property name="filter">
<bean class="com.meidusa.amoeba.server.IPAccessController">
<property name="ipFile">${amoeba.home}/conf/access_list.conf</property>
</bean>
</property>
</bean>
</property> </service> <!-- server class must implements com.meidusa.amoeba.service.Service -->
<service name="Amoeba Monitor Server" class="com.meidusa.amoeba.monitor.MonitorServer">
<!-- port -->
<!-- default value: random number
<property name="port">9066</property>
-->
<!-- bind ipAddress -->
<property name="ipAddress">127.0.0.1</property>
<property name="daemon">true</property>
<property name="manager">${clientConnectioneManager}</property>
<property name="connectionFactory">
<bean class="com.meidusa.amoeba.monitor.net.MonitorClientConnectionFactory"></bean>
</property> </service> <runtime class="com.meidusa.amoeba.mysql.context.MysqlRuntimeContext">
<!-- 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> <!-- per connection cache prepared statement size -->
<property name="statementCacheSize">500</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="clientConnectioneManager" class="com.meidusa.amoeba.net.MultiConnectionManagerWrapper">
<property name="subManagerClassName">com.meidusa.amoeba.net.ConnectionManager</property>
<!--
default value is avaliable Processors
<property name="processors">5</property>
-->
</connectionManager>
<connectionManager name="defaultManager" class="com.meidusa.amoeba.net.MultiConnectionManagerWrapper">
<property name="subManagerClassName">com.meidusa.amoeba.net.AuthingableConnectionManager</property> <!--
default value is avaliable Processors
<property name="processors">5</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>
<!-- 默认数据库，主数据库 -->
<property name="defaultPool">master</property> <!-- 写数据库 -->
<property name="writePool">master</property>
<!-- 读数据库，dbServer.xml 中配置的 虚拟数据库，数据库池 -->
<property name="readPool">slaves</property> <property name="needParse">true</property>
</queryRouter>
</amoeba:configuration>
rule.xml
<?xml version="1.0" encoding="gbk"?>
<!DOCTYPE amoeba:rule SYSTEM "rule.dtd"> <amoeba:rule xmlns:amoeba="http://amoeba.meidusa.com/">
<tableRule name="message" schema="test" defaultPools="server1">
</tableRule>
</amoeba:rule>
不需要 数据库分片时，不用配置。 但是不能没有 tableRule 元素， 否则报错。 随便写个空规则就行了。
3. 测试读写分离
a. 在 Master ， Slave1 ， Slave2 中分别查看 日志文件： mysql.log
tail -f ./log/mysql.log
b. 启动 Amoeba， 使用 Mysql GUI Tools 连接 Amoeba
执行以上几个命令。 查看日志内容。
Master mysql.log
[mysql@prx1 mysql]$ tail -f log/mysql.log
370 Query SET SESSION sql_mode=''
370 Query SET NAMES utf8
370 Query SHOW FULL TABLES
370 Query SHOW COLUMNS FROM `t_message`
370 Query SHOW COLUMNS FROM `t_user`
370 Query SHOW PROCEDURE STATUS
370 Query SHOW FUNCTION STATUS
110813 15:21:11 370 Query SHOW VARIABLES LIKE 'character_set_server'
370 Query SHOW FULL COLUMNS FROM `test`.`t_message`
110813 15:21:12 370 Query SHOW CREATE TABLE `test`.`t_message`
110813 15:22:40 374 Connect test_user@192.168.14.129 on test
375 Connect test_user@192.168.14.129 on test
376 Connect test_user@192.168.14.129 on test
110813 15:23:40 370 Query insert into t_message values(1, 'c1')
110813 15:24:07 377 Connect test_user@192.168.14.129 on test
378 Connect test_user@192.168.14.129 on test
379 Connect test_user@192.168.14.129 on test
110813 15:24:15 370 Query insert into t_user values(8, 'n8', 'p8')
110813 15:24:24 370 Query SHOW FULL COLUMNS FROM `test`.`t_user`
370 Query SHOW CREATE TABLE `test`.`t_user`
110813 15:24:35 370 Query SHOW FULL COLUMNS FROM `test`.`t_message`
370 Query SHOW CREATE TABLE `test`.`t_message`
Slave1 mysql.log
[mysql@prx2 mysql]$ tail -f log/mysql.log
317 Connect test_user@192.168.14.129 on test
318 Connect test_user@192.168.14.129 on test
110813 15:35:30 315 Query SELECT @@sql_mode
110813 15:35:32 315 Query SELECT @@sql_mode
110813 15:35:44 315 Query SELECT @@SQL_MODE
110813 15:35:46 315 Query SELECT @@SQL_MODE
110813 15:37:18 319 Connect test_user@192.168.14.129 on test
320 Connect test_user@192.168.14.129 on test
110813 15:37:19 321 Connect test_user@192.168.14.129 on test
110813 15:37:26 246 Quit
110813 15:38:21 315 Query SELECT @@SQL_MODE
110813 15:38:22 42 Query BEGIN
42 Query insert into t_message values(1, 'c1')
42 Query COMMIT /* implicit, from Xid_log_event */
110813 15:38:50 322 Connect test_user@192.168.14.129 on test
323 Connect test_user@192.168.14.129 on test
324 Connect test_user@192.168.14.129 on test
110813 15:38:58 42 Query BEGIN
42 Query insert into t_user values(8, 'n8', 'p8')
42 Query COMMIT /* implicit, from Xid_log_event */
110813 15:39:08 315 Query SELECT @@SQL_MODE
110813 15:39:19 315 Query SELECT @@SQL_MODE
110813 15:44:08 325 Connect test_user@192.168.14.129 on test
326 Connect test_user@192.168.14.129 on test
327 Connect test_user@192.168.14.129 on test
Slave2 mysql.log
[mysql@prx3 mysql]$ tail -f log/mysql.log
110813 15:35:08 305 Connect test_user@192.168.14.129 on test
306 Connect test_user@192.168.14.129 on test
307 Connect test_user@192.168.14.129 on test
110813 15:35:31 304 Query SELECT @@sql_mode
304 Query SELECT @@sql_mode
110813 15:35:44 304 Query SELECT @@SQL_MODE
110813 15:35:46 304 Query SELECT * FROM t_message t
110813 15:37:18 308 Connect test_user@192.168.14.129 on test
309 Connect test_user@192.168.14.129 on test
310 Connect test_user@192.168.14.129 on test
110813 15:38:21 8 Query BEGIN
8 Query insert into t_message values(1, 'c1')
8 Query COMMIT /* implicit, from Xid_log_event */
110813 15:38:50 311 Connect test_user@192.168.14.129 on test
312 Connect test_user@192.168.14.129 on test
313 Connect test_user@192.168.14.129 on test
110813 15:38:58 304 Query SELECT @@SQL_MODE
8 Query BEGIN
8 Query insert into t_user values(8, 'n8', 'p8')
8 Query COMMIT /* implicit, from Xid_log_event */
110813 15:39:08 304 Query select * from t_user
110813 15:39:19 304 Query select * from t_message
110813 15:44:08 314 Connect test_user@192.168.14.129 on test
315 Connect test_user@192.168.14.129 on test
316 Connect test_user@192.168.14.129 on test
从日志中可以看出。
在 Master mysql.log 中，只执行了 insert into 命令。
在 Slave1 中，只是复制了 insert into 命令， 是主从复制的结果
在 Slave2 中， 复制了 insert into 命令，同时还执行了 select 命令。
说明，主从分离已经成功。
转自：http://www.iteye.com/topic/1113437