MySQL主从复制与读写分离（实践篇）

Posted 2021-03-23

mysql主从复制的类型

基于语句的复制(默认)

• 在主服务器上执行的语句，从服务器执行同样的语句

基于行的复制

• 把改变的内容复制到从服务器

混合类型的复制

• 一旦发现基于语句无法精确复制时，就会采用基于行的复制

主从复制的过

MySQL读写分离原理

• 读写分离就是只在主服务器上写，只在从服务器上读
• 主数据库处理事务性查询，而从数据库处理select查询
• 数据库复制被用来把事务性查询导致的变更同步到集群中的从数据库

读写分离的过程

实践操作

实验环境

amoeba服务器IP地址：192.168.144.160
master服务器IP地址：192.168.144.151
slave1服务器IP地址：192.168.144.163
slave2服务器IP地址：192.168.144.145
client客户端

在master服务器上安装ntp时间服务器

[root@ameoba ~]# yum install ntp -y   //安装时间服务器
[root@master1 ~]# vim /etc/ntp.conf 
##在server下添加
server 127.127.144.0      //本地是时间源
fudge 127.127.144.0 stratum 8   //设置时间层级为8

[root@master1 ~]# systemctl start ntpd    //启动时间服务
[root@master1 ~]# systemctl stop firewalld   //关闭防火墙
[root@master1 ~]# setenforce 0

在slave1上安装ntp，ntpdate服务

[root@slave1 ~]# yum install ntp ntpdate -y
[root@slave1 ~]# systemctl start ntpd
[root@slave1 ~]# systemctl stop firewalld
[root@slave1 ~]# setenforce 0
[root@slave1 ~]# /usr/sbin/ntpdate 192.168.144.151    //同步主服务器时间
29 Nov 16:58:43 ntpdate[4932]: the NTP socket is in use, exiting

在slave2上安装ntp，ntpdate服务

[root@slave2 ~]# yum install ntp ntpdate -y
[root@slave2 ~]# systemctl start ntpd
[root@slave2 ~]# systemctl stop firewalld
[root@slave2 ~]# setenforce 0
[root@slave2 ~]# /usr/sbin/ntpdate 192.168.144.151
29 Nov 17:02:08 ntpdate[4850]: the NTP socket is in use, exiting

在master，slave1，slave2上分别安装MySQL-5.5.24

[root@master1 ~]# mkdir /abc   //创建挂载点
[root@master1 ~]# mount.cifs //192.168.100.8/LNMP-C7 /abc/   //远程挂载
Password for root@//192.168.100.8/LNMP-C7:  
[root@master1 ~]# cd /abc/
[root@master1 abc]# ls
mysql-5.5.24
[root@master1 abc]# tar zxvf mysql-5.5.24.tar.gz -C /opt/   //解压
[root@master1 opt]# yum install -y > gcc gcc-c++ > ncurses > ncurese-devel     //控制终端屏幕显示的库
> bison                  //语法分析
> make
> cmake                 //cmake工具
> libaio-devel         //系统调用来实现异步IO

[root@slave1 opt]# useradd -s /sbin/nologin mysql   //添加不可登录的mysql用户
[root@slave1 opt]# cd /opt/mysql-5.5.24/
[root@slave1 mysql-5.5.24]# mkdir /usr/local/mysql   //创建安装目录
[root@slave1 mysql-5.5.24]# cmake       //配置
> -DCMAKE_INSTALL_PREFIX=/usr/local/mysql     //安装路径
> -DMYSQL_UNIX_ADDR=/home/mysql/mysql.sock    //sock文件路径
> -DDEFAULT_CHARSET=utf8       //字符集
> -DDEFAULT_COLLATION=utf8_general_ci > -DWITH_EXTRA_CHARSETS=all > -DWITH_MYISAM_STORAGE_ENGINE=1      //存储引擎
> -DWITH_INNOBASE_STORAGE_ENGINE=1 > -DWITH_MEMORY_STORAGE_ENGINE=1 > -DWITH_READLINE=1 > -DENABLED_LOCAL_INFILE=1 > -DMYSQL_DATADIR=/home/mysql      //数据文件路径
> -DMYSQL_USER=mysql       //用户
> -DMYSQL_TCP_PORT=3306    //端口

[root@slave1 mysql-5.5.24]# make && make install   //编译及安装
[root@master1 mysql-5.5.24]# chown -R mysql.mysql /usr/local/mysql   //设置mysql属主属组
[root@master1 mysql-5.5.24]# vim /etc/profile   //配置环境变量便于系统识别
export PATH=$PATH:/usr/local/mysql/bin/
[root@master1 mysql-5.5.24]# source /etc/profile   //刷新配置文件
[root@master1 mysql-5.5.24]# cp support-files/my-medium.cnf /etc/my.cnf   //主配置文件
cp：是否覆盖"/etc/my.cnf"？ yes
[root@master1 mysql-5.5.24]# cp support-files/mysql.server /etc/init.d/mysqld   //启动文件
[root@master1 mysql-5.5.24]# chmod 755 /etc/init.d/mysqld    //设置权限
[root@master1 mysql-5.5.24]# chkconfig --add /etc/init.d/mysqld    //添加到service管理中
[root@master1 mysql-5.5.24]# chkconfig mysqld --level 35 on   //开机自启动
[root@master1 mysql-5.5.24]# /usr/local/mysql/scripts/mysql_install_db    //初始化数据库
> --user=mysql > --ldata=/var/lib/mysql > --basedir=/usr/local/mysql > --datadir=/home/mysql

[root@master1 mysql-5.5.24]# vim /etc/init.d/mysqld    //编辑启动脚本文件
basedir=/usr/local/mysql   //找到此处添加路径
datadir=/home/mysql
[root@master1 mysql-5.5.24]# service mysqld start    //启动MySQL
Starting MySQL.. SUCCESS! 
[root@master1 mysql-5.5.24]# mysqladmin -u root password ‘abc123‘  //设置密码

配置master主服务器

[root@master1 mysql-5.5.24]# vim /etc/my.cnf
server-id       = 11     //服务ID号
log-bin=master-bin                         //主服务器日志文件
log-slave-updates=true                   //从服务器更新二进制日志
[root@master1 mysql-5.5.24]# service mysqld restart   //重启MySQL服务
Shutting down MySQL. SUCCESS! 
Starting MySQL.. SUCCESS!
[root@master1 ~]# mysql -uroot -pabc123   //进入数据库

mysql> GRANT REPLICATION SLAVE ON *.* TO ‘myslave‘@‘192.168.144.%‘ IDENTIFIED BY ‘123456‘;    //给从服务器提权复制权限，名为myslave密码123456对于144段网段
Query OK, 0 rows affected (0.01 sec)

mysql> FLUSH PRIVILEGES;    ##刷新提权
Query OK, 0 rows affected (0.00 sec)

mysql> show master status;   ##查看主服务器状态
+-------------------+----------+--------------+------------------+
| File              | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+-------------------+----------+--------------+------------------+
| master-bin.000002 |      338 |              |                  |
+-------------------+----------+--------------+------------------+
1 row in set (0.00 sec)

配置slave1从服务器

[root@slave1 mysql-5.5.24]# vim /etc/my.cnf
server-id       = 22              //另外一台为23

relay-log=relay-log-bin                         //从主服务器上同步日志文件记录到本地
relay-log-index=slave-relay-bin.index           //定义relay-log的位置和名称
[root@slave1 mysql-5.5.24]# service mysqld restart    //重新服务
Shutting down MySQL. SUCCESS!  
Starting MySQL.. SUCCESS!
[root@slave1 mysql-5.5.24]# mysql -uroot -pabc123

mysql> change master to master_host=‘192.168.144.151‘,master_user=‘myslave‘,master_password=‘123456‘,master_log_file=‘master-bin.000002‘,master_log_pos=338;    //同步主服务器二进制文件和位置使用授权的账号密码
Query OK, 0 rows affected (0.00 sec)

mysql> start slave;     //开启同步
Query OK, 0 rows affected (0.01 sec)

mysql> show slave statusG;   ##查看状态
                            Master_Log_File: master-bin.000002
                    Read_Master_Log_Pos: 338
                             Relay_Log_File: relay-log-bin.000001
                                Relay_Log_Pos: 4
                Relay_Master_Log_File: master-bin.000002
                         Slave_IO_Running: Yes
                        Slave_SQL_Running: Yes

配置slave2从服务器

[root@slave2 mysql-5.5.24]# vim /etc/my.cnf
server-id       = 23              

relay-log=relay-log-bin                         //从主服务器上同步日志文件记录到本地
relay-log-index=slave-relay-bin.index           //定义relay-log的位置和名称
[root@slave2 mysql-5.5.24]# service mysqld restart    //重新服务
Shutting down MySQL. SUCCESS!  
Starting MySQL.. SUCCESS!
[root@slave2 mysql-5.5.24]# mysql -uroot -pabc123

mysql> change master to master_host=‘192.168.144.151‘,master_user=‘myslave‘,master_password=‘123456‘,master_log_file=‘master-bin.000002‘,master_log_pos=338;    //同步主服务器二进制文件和位置使用授权的账号密码
Query OK, 0 rows affected (0.00 sec)

mysql> start slave;    //开启同步
Query OK, 0 rows affected (0.01 sec)

mysql> show slave statusG;    //查看状态
                            Master_Log_File: master-bin.000002
                    Read_Master_Log_Pos: 338
                             Relay_Log_File: relay-log-bin.000001
                                Relay_Log_Pos: 4
                Relay_Master_Log_File: master-bin.000002
                         Slave_IO_Running: Yes
                        Slave_SQL_Running: Yes

测试同步情况

Master

mysql> create database school;    //创建school数据库
Query OK, 1 row affected (0.00 sec)

Slave1

mysql> show databases;   //查看数据库,实现主从同步
+--------------------+
| Database           |
+--------------------+
| information_schema |
| #mysql50#.mozilla  |
| mysql              |
| performance_schema |
| school             |
| test               |
+--------------------+
6 rows in set (0.01 sec)

Slave2

mysql> show databases;   //查看数据库,实现主从同步
+--------------------+
| Database           |
+--------------------+
| information_schema |
| #mysql50#.mozilla  |
| mysql              |
| performance_schema |
| school             |
| test               |
+--------------------+
6 rows in set (0.01 sec)

配置amoeba服务器

[root@amoeba ~]# systemctl stop firewalld.service   //关闭防火墙
[root@amoeba ~]# setenforce 0
[root@amoeba ~]# mount.cifs //192.168.100.8/LNMP-C7 /mnt/  //挂载
Password for root@//192.168.100.8/LNMP-C7:  
[root@amoeba ~]# cd /mnt/
[root@amoeba mnt]# ls
[root@amoeba mnt]# cp jdk-6u14-linux-x64.bin /usr/local/   //复制jdk二进制文件到/usr/local下
[root@amoeba mnt]# cd /usr/local/
[root@amoeba local]# ./jdk-6u14-linux-x64.bin      //直接执行安装
Do you agree to the above license terms? [yes or no]
yes                //选择yes进行安装
Press Enter to continue.....
##回车继续
[root@amoeba local]# mv jdk1.6.0_14/ /usr/local/jdk1.6         //简化文件名
[root@amoeba local]# vim /etc/profile         //设置环境变量
...
export JAVA_HOME=/usr/local/jdk1.6            //家目录
export CLASSPATH=$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib            //class环境变量
export PATH=$JAVA_HOME/lib:$JAVA_HOME/jre/bin/:$PATH:$HOME/bin           //环境变量
export AMOEBA_HOME=/usr/local/amoeba                  //amoeba家目录
export PATH=$PATH:$AMOEBA_HOME/bin                //环境变量
[root@amoeba local]# source /etc/profile            //刷新配置文件
[root@amoeba local]# mkdir /usr/local/amoeba         //创建amoeba目录
[root@amoeba local]# cd /mnt/
[root@amoeba mnt]# tar zxvf amoeba-mysql-binary-2.2.0.tar.gz -C /usr/local/amoeba      //解压amoeba压缩包
[root@amoeba mnt]# chmod -R 755 /usr/local/amoeba/            //设置权限
[root@amoeba mnt]# /usr/local/amoeba/bin/amoeba                //检查是否安装成功
amoeba start|stop

在master，slave1，slave2上授权amoeba访问

grant all on *.* to test@‘192.168.144.%‘ identified by ‘123.com‘;    //给amoeba访问权限用户test密码123.com

回到amoeba服务器修改配置文件

[root@amoeba conf]# vim amoeba.xml       //修改主配置文件
---30行--
 <property name="user">amoeba</property>        //从服务器同步主服务器的用户密码
----32行---------
 <property name="password">123456</property>
---117-去掉注释-
 <property name="defaultPool">master</property>
 <property name="writePool">master</property>
 <property name="readPool">slaves</property>
:wq
[root@amoeba conf]# vim conf/dbServers.xml       //配置数据库配置文件
--26-29--去掉注释--
 <property name="user">test</property>

 <property name="password">123.com</property>
-----42-主服务器地址---
<dbServer name="master"  parent="abstractServer">
 <property name="ipAddress">192.168.144.151</property>
--52-从服务器主机名-
<dbServer name="slave1"  parent="abstractServer">
 <property name="ipAddress">192.168.144.163</property>
 ##复制6行添加slave2
 <dbServer name="slave2"  parent="abstractServer">
 <property name="ipAddress">192.168.144.145</property>
--65行左右--
 <dbServer name="slaves" virtual="true">
 <poolConfig class="com.meidusa.amoeba.server.MultipleServerPool">
--末尾--
<property name="poolNames">slave1,slave2</property>
 </poolConfig>
[root@amoeba conf]# /usr/local/amoeba/bin/amoeba start&      //开启amoeba服务
[root@amoeba ~]# netstat -anpt | grep java           //开启另一个终端查看开启情况
tcp6       0      0 127.0.0.1:26268         :::*                    LISTEN      40925/java          
tcp6       0      0 :::8066                 :::*                    LISTEN      40925/java          
tcp6       0      0 192.168.144.160:34090    192.168.144.151:3306     ESTABLISHED 40925/java          
tcp6       0      0 192.168.144.160:33866    192.168.144.145:3306     ESTABLISHED 40925/java          
tcp6       0      0 192.168.144.160:55984    192.168.144.163:3306     ESTABLISHED 40925/java 

在客户端测试读写分离

[root@client ~]# yum install mysql -y      //安装测试数据库

client创建表

[root@client ~]# mysql -u amoeba -p123456 -h 192.168.144.160 -P8066     //使用amoeba账户密码登录amoeba
MySQL [(none)]> show databases;   //查看数据库
+--------------------+
| Database           |
+--------------------+
| information_schema |
| #mysql50#.mozilla  |
| mysql              |
| performance_schema |
| school             |
| test               |
+--------------------+
6 rows in set (0.00 sec)

MySQL [(none)]> use school;        //使用数据库
Database changed
MySQL [school]> create table info (         //创建表
        -> id int(4) not null primary key,
        -> name varchar(10) not null,
        -> score decimal(4,1) not null);
Query OK, 0 rows affected (0.02 sec)

查看主从服务器上是否有创建的表

mysql> use school;    ##使用数据库
Database changed
mysql> show tables;  ##查看表
+------------------+
| Tables_in_school |
+------------------+
| info             |
+------------------+
1 row in set (0.00 sec)

在两台从服务器上关闭同步slave

mysql> stop slave;
Query OK, 0 rows affected (0.01 sec)

在client上写入表数据

MySQL [school]> insert into info (id,name,score) values (1,‘zhangsan‘,88);  //插入数据内容
Query OK, 1 row affected (0.03 sec)

在Master上查看

mysql> select * from info;
+----+----------+-------+
| id | name     | score |
+----+----------+-------+
|  1 | zhangsan |  88.0 |
+----+----------+-------+
1 row in set (0.00 sec)

在从服务器上查看

mysql> select * from info;  //slave上没有写入
Empty set (0.00 sec)

在client查看

mysql> insert into info (id,name,score) values (2,‘lisi‘,70);
Query OK, 1 row affected (0.00 sec)

在slave2写入内容

mysql> insert into info (id,name,score) values (3,‘wuwang‘,60);
Query OK, 1 row affected (0.00 sec)

在测试机上查看info表数据（轮询的方式）

MySQL [school]> select * from info;
+----+--------+-------+
| id | name   | score |
+----+--------+-------+
|  3 | wuwang |  60.0 |
+----+--------+-------+
1 row in set (0.00 sec)

MySQL [school]> select * from info;
+----+------+-------+
| id | name | score |
+----+------+-------+
|  2 | lisi |  70.0 |
+----+------+-------+
1 row in set (0.00 sec)