MySQL负载均衡架构图如下：
一、分别在192.168.150.130和192.168.150.131上安装mysql
二、配置master（192.168.150.130）
1、编辑/etc/my.cnf，添加如下(如etc没my.cnf，cp /usr/local/mysql/support-files/my-medium.cnf /etc/my.cnf)
log-bin=mysql-bin #slave会基于此log-bin来做replication
server-id=1 #master的标识，说明是主数据库
binlog-do-db = mark #用于主从同步数据库
2、赋予权限给slave服务器的slave数据库
mysql> GRANT REPLICATION SLAVE ON *.* TO root@192.168.150.131 IDENTIFIED BY '111111';
3、重启mysql，使得配置生效
/usr/local/mysql/bin/mysqladmin shutdown
/usr/local/mysql/bin/mysqld_safe --user=mysql& 或
/usr/local/mysql/bin/safe_mysqld
4、查看master状态
mysql>show master status;
File Position Binlog_Do_DB Binlog_Ignore_DB
mysql-bin.000003 98 mark
三、配置slave（192.168.150.131）
1、编辑/etc/my.cnf，添加以下配置：(如etc没my.cnf，cp /usr/local/mysql/support-files/my-medium.cnf /etc/my.cnf)
server-id=2 #slave的标识
2、连接主数据库（master），并启动
mysql> stop slave;
mysql> CHANGE MASTER TO
-> MASTER_HOST='192.168.150.130',
-> MASTER_USER='root',
-> MASTER_PASSWORD='111111',
-> MASTER_LOG_FILE='mysql-bin.000003',
-> MASTER_LOG_POS=98;
mysql> start slave;
mysql> show slave status\G # 查看slave状态
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
3、如果出现类似字样，如
the server is not configured as slave。。。。
解决方案：
mysql> set global server_id = 2;
4、验证master-slave搭建生效
4.1、通过查看slave机的log（/var/log/mysqld.log 或 /usr/local/mysql/data/localhost.localdomain.err）：
100703 10:51:42 [Note] Slave I/O thread: connected to master 'root@192.168.150.130:3306', replication started in log 'mysql-bin.000003' at position 98
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
4.2、在master
mysql>create database mark;
use mark;
create table emp(id int,name varchar(100));
4.3、在slave
mysql>create database mark;
use mark;
create table emp(id int,name varchar(100));
4.4、在master
insert into emp values(1,'mark1');
insert into emp values(2,'mark2');
select * from emp;
4.5、查看slave数据库
select * from emp;
与master数据一致表示同步成功！！
四、安装配置amoeba，实现负载均衡
1、amoeba是基于java运行的，所以要先装jdk
# chmod +x jdk-1_5_0_16-linux-i586-rpm.bin
# ./ jdk-1_5_0_16-linux-i586-rpm.bin
# vi /etc/profile //在文件里面添加jdk的环境变量,添加内容如下
JAVA_HOME=/usr/java/jdk1.5.0_16
export JAVA_HOME
PATH=$JAVA_HOME/bin:$PATH
export PATH
CLASSPATH=$JAVA_HOME/lib/tools.jar:$JAVA_HOME/lib/dt.jar:$CLASSPATH
export CLASSPATH
# source /etc/profile
2、安装amoeba，并配置（注意：我的amoeba装在192.168.150.130，因为内存不够，开不起三个虚拟机 T_T，所以amoeba和master数据库装在同一服务器上）
2.1、安装
tar -zxvf amoeba-mysql-1.2.1-GA.tar.gz
cp -vRp /root/amoeba-mysql-1.2.1-GA /usr/local/amoeba
2.2、配置
vi /usr/local/amoeba/conf/amoeba.xml
如下：
<?xml version="1.0" encoding="gbk"?>
<!DOCTYPE amoeba:configuration SYSTEM "amoeba.dtd">
<amoeba:configuration xmlns:amoeba="http://amoeba.meidusa.com/">
<server>
<!-- proxy server绑定的端口 -->
<property name="port">8006</property>
<!-- proxy server绑定的IP -->
<!--
<property name="ipAddress">192.168.150.130</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>
<!-- query timeout( default: 60 second , TimeUnit:second) -->
<property name="queryTimeout">60</property>
</server>
<!--
每个ConnectionManager都将作为一个线程启动。
manager负责Connection IO读写/死亡检测
-->
<connectionManagerList>
<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>
<dbServerList>
<!--
一台mysqlServer 需要配置一个pool，
如果多台 平等的mysql需要进行loadBalance，
平台已经提供一个具有负载均衡能力的objectPool：com.meidusa.amoeba.mysql.server.MultipleServerPool
简单的配置是属性加上 virtual="true",该Pool 不允许配置factoryConfig
或者自己写一个ObjectPool。
-->
<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">192.168.150.130</property>
<property name="schema">mark</property>
<!-- 用于登陆mysql的用户名 -->
<property name="user">master</property>
<!-- 用于登陆mysql的密码 -->
<property name="password">master</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">192.168.150.131</property>
<property name="schema">mark</property>
<!-- 用于登陆mysql的用户名 -->
<property name="user">slave</property>
<!-- 用于登陆mysql的密码 -->
<property name="password">slave</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="multiPool" virtual="true">
<poolConfig class="com.meidusa.amoeba.server.MultipleServerPool">
<!-- 负载均衡参数 1=ROUNDROBIN , 2=WEIGHTBASED , 3=HA-->
<property name="loadbalance">1</property>
<!-- 参与该pool负载均衡的poolName列表以逗号分割 -->
<property name="poolNames">server2</property>
</poolConfig>
</dbServer>
</dbServerList>
<queryRouter class="com.meidusa.amoeba.mysql.parser.MysqlQueryRouter">
<property name="ruleConfig">${amoeba.home}/conf/rule.xml</property>
<property name="functionConfig">${amoeba.home}/conf/functionMap.xml</property>
<property name="ruleFunctionConfig">${amoeba.home}/conf/ruleFunctionMap.xml</property>
<property name="LRUMapSize">1500</property>
<property name="defaultPool">server1</property>
<property name="writePool">server1</property>
<property name="readPool">mutilPool</property>
<property name="needParse">true</property>
</queryRouter>
</amoeba:configuration>
2.3、赋予权限
主数据库，赋予权限
mysql> grant all privileges on *.* to master@'192.168.150.130' identified by 'master';
从数据库，赋予权限
mysql> grant all privileges on *.* to slave@'192.168.150.130' identified by 'slave';
2.4、重启amoeba
/usr/local/amoeba/bin/amoeba stop
/usr/local/amoeba/bin/amoeba start
2.5、测试
2.5.1、编辑amoeba_insert.php
<?php
$con = mysql_connect("192.168.150.130:8006","root","root");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
mysql_select_db("mark", $con);
$r = mysql_query("INSERT INTO emp VALUES (999,'mark999')");
if($r>0){
echo "插入了";
}
mysql_close($con);
2.5.2、编辑amoeba_select.php
<?php
$con = mysql_connect("192.168.150.130:8006","root","root");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
mysql_select_db("mark", $con);
$result = mysql_query("select * from emp;");
while($row = mysql_fetch_array($result)){
echo $row['id']."--".$row['name'];
echo '<br />';
}
mysql_close($con);
2.5.3、访问amoeba_insert.php和amoeba_select.php来测试
2.6、可能遇到的问题！！！！！！！
1、执行amoeba的命令，不够权限的话
方案1、chmod -R +x /usr/local/amoeba/bin/
2、遇到连接错误，如
ERROR 1130: Host '192.168.1.3' is not allowed to connect to this MySQL
或
Lost connection to MySQL server during query
方案1、赋予权限给新的用户
mysql> GRANT ALL PRIVILEGES ON *.* TO myuser@192.168.1.3 IDENTIFIED BY 'mypassword'
方案2、防火墙问题
vi /etc/sysconfig/iptables ，添加如下
-A INPUT -m state –state NEW -m tcp -p tcp –dport 80 -j ACCEPT（允许80端口通过防火墙）
-A INPUT -m state –state NEW -m tcp -p tcp –dport 3306 -j ACCEPT（允许3306端口通过防火墙）
重启网络 service network restart