centos 7之 mysql多实例

#查看内核版本

[root@localhost ~]# uname  -r
3.10.0-327.el7.x86_64
[root@localhost ~]# cat /etc/centos-release
CentOS Linux release 7.2.1511 (Core) 

#安装包开启服务

yum install mariadb-server -y
systemctl start mariadb

#准备三个实例的目录

mkdir -pv /mysql/{3306,3307,3308}/{data,etc,socket,log,bin,pid} 
chown -R mysql.mysql /mysql

#生成数据库文件

mysql_install_db --datadir=/mysql/3306/data --user=mysql 
mysql_install_db --datadir=/mysql/3307/data --user=mysql 
mysql_install_db --datadir=/mysql/3308/data --user=mysql

#准备配置文件. 3307 3308 同样的方法

[root@localhost ~]# cat /mysql/3306/etc/my.cnf
[client-server]
[mysqld]
port=3306
datadir=/mysql/3306/data/
socket=/mysql/3306/socket/mysql.sock
[mysqld_safe]
log-error=/mysql/3306/log/mariadb.log
pid-file=/mysql/3306/pid/mariadb.pid
!includedir /etc/my.cnf.d

#准备脚本文件

[root@localhost ~]# cat /mysql/3306/bin/mysqld
#!/bin/bash
port=3306
mysql_user="root"
mysql_pwd="magedu"
cmd_path="/usr/bin"
mysql_basedir="/mysql"
mysql_sock="${mysql_basedir}/${port}/socket/mysql.sock"

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

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

function_restart_mysql(){
    printf "Restarting MySQL.../n"
    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}/n"
esac

#重复上述过程，分别建立3307，3308的启动脚本

[root@localhost ~]# cp   /mysql/3306/bin/mysqld  /mysql/3307/bin/mysqld
[root@localhost ~]# sed -rin 's#3306#3307#p' /mysql/3307/bin/mysqld

[root@localhost ~]# cp   /mysql/3306/bin/mysqld  /mysql/3308/bin/mysqld
[root@localhost ~]# sed -rin 's#3306#3308#p' /mysql/3308/bin/mysqld

#启动关闭服务

[root@localhost ~]# systemctl stop  mariadb    #停止之前的mariadb
[root@localhost ~]# /mysql/3306/bin/mysqld start  #开启实例3306
Starting MySQL...
[root@localhost ~]# ss -tnl
State      Recv-Q Send-Q                      Local Address:Port                                     Peer Address:Port              
LISTEN     0      128                                     *:22                                                  *:*                  
LISTEN     0      100                             127.0.0.1:25                                                  *:*                  
LISTEN     0      80                                     :::3306                                               :::*                  
LISTEN     0      128                                    :::22                                                 :::*                  
LISTEN     0      100                                   ::1:25                                                 :::*                  
[root@localhost ~]# /mysql/3306/bin/mysqld stop #关闭实例3306
Stoping MySQL...
[root@localhost ~]# ss -tnl
State      Recv-Q Send-Q                      Local Address:Port                                     Peer Address:Port              
LISTEN     0      128                                     *:22                                                  *:*                  
LISTEN     0      100                             127.0.0.1:25                                                  *:*                  
LISTEN     0      128                                    :::22                                                 :::*                  
LISTEN     0      100                                   ::1:25                                                 :::*                  

#同理：开启3307 3308 的实例

/mysql/3306/bin/mysqld  start

/mysql/3307/bin/mysqld  start

/mysql/3308/bin/mysqld  start

#登录实例

/mysql/3306/bin/mysqld  start

mysql -uroot -S /mysql/3306/socket/mysql.sock 

mariadb>show variables like 'port';  #确认连接的端口

MariaDB [(none)]> create database  3307_db;    #创建数据库
Query OK, 1 row affected (0.001 sec)
MariaDB [(none)]> system ls /mysql/3307/data/3307_db -d  ;  #在该文件下就生成了目录
/mysql/3307/data/3307_db

#修改root密码

[root@localhost ~]# /mysql/3306/bin/mysqld start 
Starting MySQL...
[root@localhost ~]# mysqladmin -uroot -S /mysql/3306/socket/mysql.sock password '123456'  #加上新口令

#重复步骤，分别修改别外两个实例3307，3308对应root口令

#测试连接

[root@localhost ~]# /mysql/3306/bin/mysqld start
Starting MySQL...
[root@localhost ~]# /mysql/3307/bin/mysqld start
Starting MySQL...
[root@localhost ~]# /mysql/3308/bin/mysqld start
Starting MySQL...
[root@localhost ~]# mysql -uroot -S /mysql/3306/socket/mysql.sock -p123456    #该方法只适合本机连接
Welcome to the MariaDB monitor.  Commands end with ; or /g.
Your MariaDB connection id is 8
Server version: 10.4.21-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '/h' for help. Type '/c' to clear the current input statement.

MariaDB [(none)]>