关系型数据库MySQL主从同步-读写分离

1.环境准备

我的数据库版本是MySQL 5.6

MySQL主机至少两个实例，可以是多实例，可以是多台主机

关闭selinux，关闭防火墙等基础优化

---

2.安装

yum -y install make gcc-c++ cmake bison-devel  ncurses-devel
wget https://dev.mysql.com/get/Downloads/MySQL-5.6/mysql-5.6.43-linux-glibc2.12-i686.tar.gz
tar xf mysql-5.6.-linux-glibc2.-i686.tar.gz
cd mysql-5.6.-linux-glibc2.-i686
cmake -DCMAKE_INSTALL_PREFIX=/usr/local/mysql -DMYSQL_DATADIR=/usr/local/mysql/data -DSYSCONFDIR=/etc -DWITH_MYISAM_STORAGE_ENGINE= -DWITH_INNOBASE_STORAGE_ENGINE= -DWITH_MEMORY_STORAGE_ENGINE= -DWITH_READLINE= -DMYSQL_UNIX_ADDR=/var/lib/mysql/mysql.sock -DMYSQL_TCP_PORT= -DENABLED_LOCAL_INFILE= -DWITH_PARTITION_STORAGE_ENGINE= -DEXTRA_CHARSETS=all -DDEFAULT_CHARSET=utf8 -DDEFAULT_COLLATION=utf8_general_ci
make && make install
useradd -g mysql mysql
chown -R mysql:mysql /usr/local/mysql

---

3.多实例

192.168.0.11:3308主

192.168.0.11:3309从

安装数据库

mkdir /data/mysql56/mysql{,}/data -p
/usr/local/mysql/scripts/mysql_install_db --user=mysql --basedir=/usr/local/mysql --datadir=/data/mysql56/mysql3308/data   #两个ok说明成功
/usr/local/mysql/scripts/mysql_install_db --user=mysql --basedir=/usr/local/mysql --datadir=/data/mysql56/mysql3309/data

配置文件

vim /data/mysql56/mysql3308/my.cnf
[client]
port =
socket = /data/mysql56/mysql3308/mysql.sock
default-character-set = utf8
[mysqld]
skip-name-resolve
user = mysql
basedir = /usr/local/mysql
datadir = /data/mysql56/mysql3308/data
port =
server_id =
socket = /data/mysql56/mysql3308/mysql.sock
pid-file = /data/mysql56/mysql3308/mysql.pid
log-error = /data/mysql56/mysql3308/mysql.err
log-bin = /data/mysql56/mysql3308/mysql-bin
character-set-server = utf8

vim  /data/mysql56/mysql3309/my.cnf
[client]
port =
socket = /data/mysql56/mysql3309/mysql.sock
default-character-set = utf8
[mysqld]
skip-name-resolve
user = mysql
basedir = /usr/local/mysql
datadir = /data/mysql56/mysql3309/data
port =
server_id =
socket = /data/mysql56/mysql3309/mysql.sock
pid-file = /data/mysql56/mysql3309/mysql.pid
log-error = /data/mysql56/mysql3309/mysql.err
log-bin = /data/mysql56/mysql3309/mysql-bin
character-set-server = utf8

启动脚本

#!/bin/bash
mysql_bin=/usr/local/mysql//bin
mysql_port=
mysql_username="root"
mysql_password=""
mysql_dir=/data/mysql56/mysql${mysql_port}
is_run=$(ss -tunlp|grep ${mysql_port}|wc -l)

start_server(){
    $mysql_bin/mysqld_safe --defaults-file=${mysql_dir}/my.cnf >& > /dev/null &
    echo "已经运行"
}
stop_server(){
if [ ${is_run} -eq  ];then
    $mysql_bin/mysqladmin -u ${mysql_username} -p${mysql_password} -S ${mysql_dir}/mysql.sock shutdown
    echo "已经停止"
else
    echo "是停止的"
fi
}
restart_server(){
if [ ${is_run} -eq  ];then
    echo "正在重启"
    stop_server
    sleep
    start_server
    echo "重启完毕"
else
    start_server
fi
}
case $ in
start)
start_server;;
stop)
stop_server;;
restart)
restart_server;;
*)
echo "Usage: $0 {start|stop|restart|}";;
esac

mysqladmin -uroot password 123456 -S /data/mysql56/mysql3308/mysql.sock   #密码设置得和脚本一致

登录

/data/mysql56/mysql3308/mysql-server.sh start
mysql -uroot -p123456 -S /data/mysql56/mysql3308/mysql.sock

成功~

启动另一个实例

把脚本的端口改一下就可以了

cp /data/mysql56/mysql3308/mysql-server.sh /data/mysql56/mysql3309/
cd /data/mysql56/mysql3309/
./mysql-server.sh start

---

4.主从同步

1.登录主库

创建用户同步的用户

mysql> grant replication slave on *.* to rep@'192.168.0.%' identified by 'rep123';
mysql> flush privileges;

查看
mysql> show grants for rep@'192.168.0.%';
+--------------------------------------------------------------------------------------------------------------------------+
| Grants for rep@192.168..%                                                                                               |
+--------------------------------------------------------------------------------------------------------------------------+
| GRANT REPLICATION SLAVE ON *.* TO 'rep'@'192.168.0.%' IDENTIFIED BY PASSWORD '*08F5BB4670F148DB0376A1EE646F0C67EAE138CE' |
+--------------------------------------------------------------------------------------------------------------------------+
 row in set (0.00 sec)

2.主库全量备份

mysqldump -uroot -p123456 -S /data/mysql56/mysql3308/mysql.sock -B -F -R -x --master-data= -A --events >/tmp/rep3308_$(date +%F).sql

3.从库导入全量备份

mysql -uroot -p123456 -S /data/mysql56/mysql3309/mysql.sock </tmp/rep3308_$(date +%F).sql

4.开启同步

查看 主master状态

change master to master_host='192.168.0.15',master_user='rep',master_password='rep123',master_port=,master_log_file='mysql-bin.000025',master_log_pos=;

start slave;

show slave status\G

两个线程都是yes说明成功

5.读写分离

mysql-proxy是官方提供的mysql中间件产品可以实现负载平衡，读写分离，failover等

类似nginx负载平衡 zabbix-proxy功能差不多 都是转发请求

1.下载安装mysql-proxy

我们安装在另一台机器上内网ip:192.168.0.19

安装路径: /usr/local/

wget -c https://downloads.mysql.com/archives/get/file/mysql-proxy-0.8.5-linux-el6-x86-64bit.tar.gz
tar xf mysql-proxy-0.8.-linux-el6-x86-64bit.tar.gz
mv mysql-proxy-0.8.-linux-el6-x86-64bit /usr/local/mysql-proxy
cd /usr/local/mysql-proxy/
mkdir lua logs
cp share/doc/mysql-proxy/rw-splitting.lua ./lua  #复制读写分离配置文件
cp share/doc/mysql-proxy/admin-sql.lua ./lua     #复制管理脚本

2.配置文件

vi /etc/mysql-proxy.cnf
[mysql-proxy]
user=root                                                     #运行mysql-proxy用户
admin-username=mysqlproxy                                     #主从mysql共有的用户
admin-password=mysqlproxy123                                  #用户的密码
proxy-address=192.168.0.19:4040                               #mysql-proxy运行ip和端口，不加端口，默认4040
proxy-read-only-backend-addresses=192.168.0.11:3309           #指定后端从slave读取数据，不加端口默认3306
proxy-backend-addresses=192.168.0.11:3308                     #指定后端主master写入数据，不加端口默认3306
proxy-lua-script=/usr/local/mysql-proxy/lua/rw-splitting.lua  #指定读写分离配置文件位置
admin-lua-script=/usr/local/mysql-proxy/lua/admin-sql.lua     #指定管理脚本
log-file=/usr/local/mysql-proxy/logs/mysql-proxy.log          #日志位置
log-level=info                                                #定义log日志级别，由高到低分别有(error|warning|info|message|debug)
daemon=true                                                   #以守护进程方式运行
keepalive=true                                                #mysql-proxy崩溃时，尝试重启

配置文件授权

chmod  /etc/mysql-proxy.cnf

3.创建代理数据库的用户(主从都要创建)

grant all on *.* to mysqlproxy@'192.168.0.%' identified by 'mysqlproxy123';

4.修改脚本部分配置

vim /usr/local/mysql-proxy/lua/rw-splitting.lua
if not proxy.global.config.rwsplit then
 proxy.global.config.rwsplit = {
  min_idle_connections = ,                    #默认超过4个连接数时，才开始读写分离，改为1
  max_idle_connections = ,                    #默认8，改为1
  is_debug = false
 }
end

5.启动

/usr/local/mysql-proxy/bin/mysql-proxy --defaults-file=/etc/mysql-proxy.cnf

6.检查

# ss -tunlp|grep mysql-proxy
tcp    LISTEN                    192.168.0.19:                  *:*      users:(("mysql-proxy",,))

7.测试

mysql -umysqlproxy -pmysqlproxy123 -h192.168.0. --port=

主库版本是5.6.28 从库是5.6.14

说明我连接上去查询语句是从从库返回的