CentOS安装MySQL5.7多实例步骤详解

本次安装Mysql的CentOS版本是7.7

1.下载Mysql

首先去Mysql官网下载安装包，网址https://dev.mysql.com/downloads/mysql/,下载后将Mysql安装包上传至服务器/usr/local/目录下

2.创建Mysql用户和组

groupadd mysql #创建mysql组
useradd -r -d /home/mysql -g mysql mysql #创建mysql用户 并指定组和默认路径
chown -R mysql:mysql /home/mysql #将Mysql默认路径的用户和组改成mysql

3.解压Mysql

tar -xvf mysql-5.7.29-linux-glibc2.12-x86_64 #解压安装包
ln -s mysql-5.7.29-linux-glibc2.12-x86_64 mysql #文件夹添加软链接为mysql
chown -R mysql:mysql /usr/local/mysql #将MySQL程序路径的用户和组改成mysql

4.为Mysql安装配置环境

使用root用户编辑/etc/profile，将下面的内容添加到最下面,并执行source /etc/profile使配置生效

export PATH=$PATH:/usr/local/mysql/bin

关闭防火墙，防火墙状态为inactive时表示关闭成功

service firewalld stop

关闭SELinux，编辑/etc/selinux/config，将selinux=enforce改为disable即可

5.创建Mysql数据目录

mkdir /usr/local/mysqld_multi #创建MySQL数据母目录
mkdir /usr/local/mysqld_multi/mysql1 #为每个MySQL实例创建数据目录
mkdir /usr/local/mysqld_multi/mysql2 
mkdir /usr/local/mysqld_multi/mysql3 
mkdir /usr/local/mysqld_multi/mysql4 
chown -R mysql:mysql /usr/local/mysqld_multi #将数据目录的用户和组改成mysql
chmod -R 750 /usr/local/mysqld_multi #更改数据目录权限

6.配置my.cnf文件

新建my.cnf配置文件，并添加以下内容

[client]
default-character-set=utf8

[mysqld_multi]
mysqld = /usr/local/mysql/bin/mysqld_safe
mysqladmin = /usr/local/mysql/bin/mysqladmin
log = /usr/local/mysqld_multi/mysqld_multi.log
lower_case_table_names=1

[mysqld1]
server-id = 11
socket = /tmp/mysql.sock1
basedir=/usr/local/mysql
port = 3307
bind_address = 0.0.0.0
datadir = /usr/local/mysqld_multi/mysql1
user = mysql
performance_schema = off
innodb_buffer_pool_size = 32M
skip_name_resolve = 1
log_error = error.log
pid-file = /usr/local/mysqld_multi/mysql1/mysql.pid1


[mysqld2]
server-id = 12
socket = /tmp/mysql.sock2
basedir=/usr/local/mysql
port = 3308
bind_address = 0.0.0.0
datadir = /usr/local/mysqld_multi/mysql2
user = mysql
performance_schema = off
innodb_buffer_pool_size = 32M
skip_name_resolve = 1
log_error = error.log
pid-file = /usr/local/mysqld_multi/mysql1/mysql.pid2

[mysqld3]
server-id = 13
socket = /tmp/mysql.sock3
basedir=/usr/local/mysql
port = 3309
bind_address = 0.0.0.0
datadir = /usr/local/mysqld_multi/mysql3
user = mysql
performance_schema = off
innodb_buffer_pool_size = 32M
skip_name_resolve = 1
log_error = error.log
pid-file = /usr/local/mysqld_multi/mysql1/mysql.pid3

[mysqld4]
server-id = 14
socket = /tmp/mysql.sock4
basedir=/usr/local/mysql
port = 3310
bind_address = 0.0.0.0
datadir = /usr/local/mysqld_multi/mysql4
user = mysql
performance_schema = off
innodb_buffer_pool_size = 32M
skip_name_resolve = 1
log_error = error.log
pid-file = /usr/local/mysqld_multi/mysql1/mysql.pid4

7.初始化Mysql

依次执行下面的命令初始化MySQL各个实例

mysqld --initialize --user=mysql --datadir=/usr/local/mysqld_multi/mysql1
mysqld --initialize --user=mysql --datadir=/usr/local/mysqld_multi/mysql2
mysqld --initialize --user=mysql --datadir=/usr/local/mysqld_multi/mysql3
mysqld --initialize --user=mysql --datadir=/usr/local/mysqld_multi/mysql4

8.启动Mysql

执行mysqld_mulit start启动mysql，启动后通过mysqld_mulit report可查看各个实例的状态
也可以通过mysqld_mulit {start|stop|restart} 1分别停启MySQL实例

9.登录Mysql

通过查看各个实例数据目录下的error.log获取Mysql的初始化密码，并登录mysql

mysql -u root -p -S /tmp/mysql.sock1

10.修改root用户密码

通过下面的语句可以修改root用户的密码

set password = ‘root123‘;

为远程登录创建用户,并赋权

CREATE USER ‘root‘@‘%‘ IDENTIFIED BY ‘root123‘;
GRANT ALL ON  *.*  TO ‘root‘@‘%‘;
FLUSH PRIVILEGES;

这样就可以通过navicat等工具进行远程连接了，按照相同的方法设置可以其他三个实例的root密码

11.配置mysql开机自启

首先将mysqld_multi.server 复制到/etc/init.d下面

cp support-files/mysqld_multi.server /etc/init.d/mysqld_multid

这时通过service mysqld_multid report启动MySQL会报错，原因是service调用服务时的PATH只有/sbin:/usr/sbin:/bin:/usr/bin

将mysql的bin路径添加到/etc/init.d/mysqld_multid中即可

再通过chkconfig将mysql服务添加到开机启动的列表里面就可以了

chkconfig --add --level 123456 mysqld_multid

12.配置login-path登录

为了方便多实例登录，可以配置login-path

mysql_config_editor set -G mysql -S /tmp/mysql.sock1 -u root -p

以上就是MySQL多实例安装的全部内容了，欢迎大家交流指正