MySQL/mariadb知识点——安装篇(4)多实例配置

MySQL的多实例配置

有时候在一台物理机中需要多个测试环境，那么就有了搭建数据库的多个示例的需求；

多个实例的意思即：运行多份程序，实例与实例之间没有影响。要注意监听的端口需要不同

搭建环境：centos7.4，编译安装MariaDB-10.2.15版本,软件目录：/app/mysql/

1、创建运行的目录环境

[root@centos7 ~]# mkdir -p /mysqldb/{3306,3307,3308}/{etc,socket,pid,log,data,bin}
[root@centos7 ~]# chown -R mysql:mysql /mysqldb/

2、初始化数据库

[root@centos7 ~]# cd /app/mysql/
[root@centos7 mysql]# scripts/mysql_install_db --datadir=/mysqldb/3306/data/ --user=mysql --basedir=/app/mysql/ 
[root@centos7 mysql]# scripts/mysql_install_db --datadir=/mysqldb/3307/data/ --user=mysql --basedir=/app/mysql/
[root@centos7 mysql]# scripts/mysql_install_db --datadir=/mysqldb/3308/data/ --user=mysql --basedir=/app/mysql/

　　以上为编译安装，安装目录为/app/mysql/ 需要先进入软件的安装目录然后执行初始化脚本，如果是yum安装的包，则直接运行mysql_install_db

3、提供配置文件并按需要修改

[root@centos7 mysql]# cp support-files/my-huge.cnf /mysqldb/3306/etc/my.cnf
[root@centos7 mysql]# cp support-files/my-huge.cnf /mysqldb/3307/etc/my.cnf
[root@centos7 mysql]# cp support-files/my-huge.cnf /mysqldb/3308/etc/my.cnf

[root@centos7 mysqldb]# cd /mysqldb/
[root@centos7 mysqldb]# vim 3306/etc/my.cnf
[mysqld]
port        = 3306
datadir     = /mysqldb/3306/data
socket      = /mysqldb/3306/socket/mysql.sock
[root@centos7 mysqldb]# vim 3307/etc/my.cnf  #按以上配置示例更改
[root@centos7 mysqldb]# vim 3308/etc/my.cnf

4、提供服务启动脚本

[root@centos7 ~]# cat mysqld  #脚本示例
#!/bin/bash

port=3306  #需要修改为当前实例的端口号
mysql_user="root"
mysql_pwd=""
cmd_path="/app/mysql/bin"  #安装目录下的bin
mysql_basedir="/mysqldb"  #实例数据库文件所在目录
mysql_sock="${mysql_basedir}/${port}/socket/mysql.sock"

function_start_mysql()
{
    if [ ! -e "$mysql_sock" ];then
      printf "Starting MySQL...
"
      ${cmd_path}/mysqld_safe --defaults-file=${mysql_basedir}/${port}/etc/my.cnf  &> /dev/null  &
    else
      printf "MySQL is running...
"
      exit
    fi
}


function_stop_mysql()
{
    if [ ! -e "$mysql_sock" ];then
       printf "MySQL is stopped...
"
       exit
    else
       printf "Stoping MySQL...
"
       ${cmd_path}/mysqladmin -u ${mysql_user} -p${mysql_pwd} -S ${mysql_sock} shutdown
   fi
}


function_restart_mysql()
{
    printf "Restarting MySQL...
"
    function_stop_mysql
    sleep 2
    function_start_mysql
}

case $1 in
start)
    function_start_mysql
;;
stop)
    function_stop_mysql
;;
restart)
    function_restart_mysql
;;
*)
    printf "Usage: ${mysql_basedir}/${port}/bin/mysqld {start|stop|restart}
"
esac

　　

[root@centos7 ~]# cp mysqld /mysqldb/3306/bin/
[root@centos7 ~]# cp mysqld /mysqldb/3307/bin/
[root@centos7 ~]# cp mysqld /mysqldb/3308/bin/
[root@centos7 ~]# vim /mysqldb/3306/bin/mysqld
port=3306
[root@centos7 ~]# vim /mysqldb/3307/bin/mysqld
port=3307
[root@centos7 ~]# vim /mysqldb/3308/bin/mysqld
port=3308

5、修改脚本文件权限，防止密码被别人看到

[root@centos7 ~]# chmod 700 /mysqldb/3306/bin/mysqld 
[root@centos7 ~]# chmod 700 /mysqldb/3307/bin/mysqld  
[root@centos7 ~]# chmod 700 /mysqldb/3308/bin/mysqld 

6、启动服务

[root@centos7 ~]# service mysqld stop  #保证自己原来的服务停止，释放3306端口
[root@centos7 ~]# /mysqldb/3306/bin/mysqld start  #启动服务
[root@centos7 ~]# /mysqldb/3307/bin/mysqld start
[root@centos7 ~]# /mysqldb/3308/bin/mysqld start
[root@centos7 ~]# ss -tnl  #如果看到三个实例监听的端口都打开后说明服务启动正常
LISTEN 0 80 :::3306 :::*
LISTEN 0 80 :::3307 :::*
LISTEN 0 80 :::3308 :::*

7、连接测试

[root@centos7 ~]# mysql -S /mysqldb/3306/socket/mysql.sock  #使用-S指定套接字文件
Server version: 10.2.15-MariaDB-log Source distribution
MariaDB [(none)]> show variables like '%port';  #查看端口是否是3306
+---------------------+-------+
| Variable_name       | Value |
+---------------------+-------+
| extra_port          | 0     |
| large_files_support | ON    |
| port                | 3306  |
| report_port         | 3306  |
+---------------------+-------+
4 rows in set (0.00 sec)

[root@centos7 ~]# mysql -S /mysqldb/3307/socket/mysql.sock  #再连接测试一下3307和3308
Server version: 10.2.15-MariaDB-log Source distribution
MariaDB [(none)]> show variables like '%port';
+---------------------+-------+
| Variable_name       | Value |
+---------------------+-------+
| extra_port          | 0     |
| large_files_support | ON    |
| port                | 3307  |
| report_port         | 3307  |
+---------------------+-------+
4 rows in set (0.00 sec)

[root@centos7 ~]# mysql -S /mysqldb/3308/socket/mysql.sock
Server version: 10.2.15-MariaDB-log Source distribution
MariaDB [(none)]> show variables like '%port';
+---------------------+-------+
| Variable_name       | Value |
+---------------------+-------+
| extra_port          | 0     |
| large_files_support | ON    |
| port                | 3308  |
| report_port         | 3308  |
+---------------------+-------+
4 rows in set (0.00 sec)

*8、停止实例

[root@centos7 ~]# /mysqldb/3306/bin/mysqld stop