一.MySQL读写分离原理
主数据库处理事务性查询，从数据库处理select查询。数据库复制用来把事务性查询导致的变更同步到从数据库中。
二.最为常见的读写分离有两种：
1.基于程序代码实现
在代码中根据select，insert进程路由分类；
优点：性能好，因为在代码中实现，不需要额外的硬件设备；
缺点：需要开发人员来实现，对代码改动比较大，不适合大型复杂应用；
2.基于代理层实现
MySQL-Proxy：隶属于MySQL开源项目；
Amoeba：Amoeba是一个以MySQL为底层数据存储，并对应用提供MySQL协议接口的proxy。它集中地响应应用的请求，依据用户事先设置的规则，将SQL请求发送到特定的数据库上执行。基于此可以实现负载均衡、读写分离、高可用性等需求；
三.实验环境
OS：CentOS 6.5 x64
Amoeba：192.168.0.128
master：192.168.0.134
slave：192.168.0.135
client：192.168.0.137
三.配置主从复制
1.MySQL读写分离是基于主从复制配置的，先配置好主从复制，再配置读写分离。
主从复制博文连接：http://guoxh.blog.51cto.com/10976315/1922643
2.添加授权账号供Amoeba访问
master和slave：
mysql> grant all on *.* to ‘proxy‘@‘192.168.0.128‘ identified by ‘123456‘; Query OK, 0 rows affected (0.00 sec) mysql> flush privileges; Query OK, 0 rows affected (0.00 sec)
四.Amoeba安装配置
1. Amoeba是基于JDK开发的，所有先安装JAVA环境
[root@amoeba ~]# chmod +x jdk-6u14-linux-x64.bin [root@amoeba ~]# ./jdk-6u14-linux-x64.bin [root@amoeba ~]# cat /etc/profile.d/java.sh export JAVA_HOME=/usr/local/jdk1.6 export CLASSPATH=$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib export PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/lib:$PATH:$HOME/bin [root@amoeba ~]# source /etc/profile.d/java.sh [root@amoeba ~]# java -version java version "1.6.0_14" Java(TM) SE Runtime Environment (build 1.6.0_14-b08) Java HotSpot(TM) 64-Bit Server VM (build 14.0-b16, mixed mode) #JAVA环境配置完成
2.安装Amoeba
[root@amoeba ~]# mkdir /usr/local/amoeba [root@amoeba ~]# tar xf amoeba-mysql-binary-2.2.0.tar.gz -C /usr/local/amoeba [root@amoeba ~]# ls /usr/local/amoeba/ benchmark bin changelogs.txt conf lib LICENSE.txt README.html [root@amoeba ~]# cat /etc/profile.d/amoeba.sh export AMOEBA_HOME=/usr/local/amoeba/ export PATH=$PATH:$AMOEBA_HOME/bin [root@amoeba ~]# source /etc/profile.d/amoeba.sh [root@amoeba ~]# /usr/local/amoeba/bin/amoeba amoeba start|stop # Amoeba安装成功
3.编辑amoeba.xml配置文件
[root@amoeba conf]# cd /usr/local/amoeba/conf/
[root@amoeba conf]# cp amoeba.xml amoeba$(date +"%Y_%m_%d").xml #修改前备份一份
[root@amoeba conf]# vim amoeba.xml
27 <property name="authenticator">
28 <bean class="com.meidusa.amoeba.mysql.server.MysqlClientAuthenticator">
29
30 <property name="user">amoeba</property> #设置client连接的用户
31
32 <property name="password">amoeba</property> #设置client连接的密码
33
34 <property name="filter">
35 <bean class="com.meidusa.amoeba.server.IPAccessController">
36 <property name="ipFile">${amoeba.home}/conf/access_list.conf</property>
37 </bean>
38 </property>
39 </bean>
40 </property>
112 </property>
113 <property name="sqlFunctionFile">${amoeba.home}/conf/functionMap.xml</property>
114 <property name="LRUMapSize">1500</property>
115 <property name="defaultPool">master/property>
116
117 <!-- #删除注释
118 <property name="writePool">master</property>
119 <property name="readPool">slaves</property>
120 --> #删除注释
121 <property name="needParse">true</property>3.编辑dbServers.xml
25 <!-- mysql user --> 26 <property name="user">proxy</property> #填mysql授权的用户 27 28 <!-- mysql password --> 29 <property name="password">123456</property> #填MySQL授权的用户密码 30 45 <dbServer name="master" parent="abstractServer"> 46 <factoryConfig> 47 <!-- mysql ip --> 48 <property name="ipAddress">192.168.0.134</property> #指定master的IP 49 </factoryConfig> 50 </dbServer> 51 52 <dbServer name="slave" parent="abstractServer"> 53 <factoryConfig> 54 <!-- mysql ip --> 55 <property name="ipAddress">192.168.0.135</property> #指定slave的IP 56 </factoryConfig> 57 </dbServer> 58 <dbServer name="slaves" virtual="true"> 59 <poolConfig class="com.meidusa.amoeba.server.MultipleServerPool"> 60 <!-- Load balancing strategy: 1=ROUNDROBIN , 2=WEIGHTBASED , 3=HA--> 61 <property name="loadbalance">1</property> 62 63 <!-- Separated by commas,such as: server1,server2,server1 --> 64 <property name="poolNames">slave</property> 65 </poolConfig> 66 </dbServer>
4.启动服务
[root@amoeba ~]# amoeba start & [1] 2666 [root@amoeba ~]# log4j:WARN log4j config load completed from file:/usr/local/amoeba/conf/log4j.xml 2017-05-07 00:42:16,692 INFO context.MysqlRuntimeContext - Amoeba for Mysql current versoin=5.1.45-mysql-amoeba-proxy-2.2.0 log4j:WARN ip access config load completed from file:/usr/local/amoeba/conf/access_list.conf 2017-05-07 00:42:17,064 INFO net.ServerableConnectionManager - Amoeba for Mysql listening on 0.0.0.0/0.0.0.0:8066. 2017-05-07 00:42:17,067 INFO net.ServerableConnectionManager - Amoeba Monitor Server listening on /127.0.0.1:56460. [root@amoeba ~]# netstat -anptl | grep java tcp 0 0 ::ffff:127.0.0.1:56460 :::* LISTEN 2666/java tcp 0 0 :::8066 :::* LISTEN 2666/java tcp 0 0 ::ffff:192.168.0.128:37361 ::ffff:192.168.0.135:3306 ESTABLISHED 2666/java tcp 0 0 ::ffff:192.168.0.128:35241 ::ffff:192.168.0.134:3306 ESTABLISHED 2666/java #Amoeba默认端口为8066
五.测试
1.客户端连接Amoeba
[root@client ~]# mysql -u amoeba -p -h 192.168.0.128 -P 8066
2.新建一个数据库
mysql> create database guoxh; Query OK, 1 row affected (0.01 sec) mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | aaa | | guoxh | | mysql | | test | +--------------------+ 5 rows in set (0.01 sec)
3.master和slave查看数据库
mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | aaa | | guoxh | #刚建的数据库已经同步 | mysql | | test | +--------------------+ 5 rows in set (0.00 sec)
五.测试读写分离：
1.在master新建一个表，同步到slave上，然后关掉slave功能，在slave上插入区别语句
master：创建名为student的表
mysql> show tables; Empty set (0.00 sec) mysql> create table student (id int(10),name varchar(10),info varchar(50)); Query OK, 0 rows affected (0.01 sec) mysql> show tables; +-----------------+ | Tables_in_guoxh | +-----------------+ | student | +-----------------+ 1 row in set (0.00 sec)
slave：停止同步
mysql> show tables; +-----------------+ | Tables_in_guoxh | +-----------------+ | student | +-----------------+ 1 row in set (0.00 sec) mysql> stop slave; Query OK, 0 rows affected (0.00 sec)
master：插入区别数据
mysql> insert into student values(‘1‘,‘zhangsan‘,‘Mysql_master‘); Query OK, 1 row affected (0.01 sec) mysql> select * from student; +------+----------+--------------+ | id | name | info | +------+----------+--------------+ | 1 | zhangsan | Mysql_master | +------+----------+--------------+ 1 row in set (0.00 sec)
slave：插入区别数据
mysql> select * from student; Empty set (0.00 sec) mysql> insert into student values(‘2‘,‘lisi‘,‘Mysql_slave‘); Query OK, 1 row affected (0.00 sec) mysql> select * from student; +------+------+-------------+ | id | name | info | +------+------+-------------+ | 2 | lisi | Mysql_slave | +------+------+-------------+ 1 row in set (0.00 sec)
3.测试读操作：
client：
mysql> show tables; +-----------------+ | Tables_in_guoxh | +-----------------+ | student | +-----------------+ 1 row in set (0.00 sec) mysql> select * from student; +------+------+-------------+ | id | name | info | +------+------+-------------+ | 2 | lisi | Mysql_slave | +------+------+-------------+ 1 row in set (0.00 sec) mysql> select * from student; +------+------+-------------+ | id | name | info | +------+------+-------------+ | 2 | lisi | Mysql_slave | +------+------+-------------+ 1 row in set (0.00 sec)
# 此时，读操作已经已经全部分配到slave上面。
4.测试写操作
client：插入一条数据，这里是看不到数据的，得到master查看
mysql> insert into student values(‘3‘,‘wangwu‘,‘Mysql_client‘); Query OK, 1 row affected (0.00 sec) mysql> select * from student; +------+------+-------------+ | id | name | info | +------+------+-------------+ | 2 | lisi | Mysql_slave | +------+------+-------------+ 1 row in set (0.00 sec)
master：
mysql> select * from student; +------+----------+--------------+ | id | name | info | +------+----------+--------------+ | 1 | zhangsan | Mysql_master | | 3 | wangwu | Mysql_client | +------+----------+--------------+ 2 rows in set (0.00 sec)
#此时，写操作全部分给了master。
到此为止，MySQL已经实现了读写分离！
本文出自 “隔壁老大哥” 博客，请务必保留此出处http://guoxh.blog.51cto.com/10976315/1922770
原文地址：http://guoxh.blog.51cto.com/10976315/1922770
