环境准备，一台CentOS7
安装软件
```
[root@localhost ~]# yum install mariadb-server -y
```
创建三个实例的目录
```
[root@localhost ~]# mkdir /mysql/{3306,3307,3308}/{data,etc,socket,log,bin,pid} -p
```
改所属主，组
```
[root@localhost ~]# chown -R mysql.mysql /mysql
```
生成数据库文件
```
[root@localhost ~]# mysql_install_db --user=mysql --datadir=/mysql/3306/data
[root@localhost ~]# mysql_install_db --user=mysql --datadir=/mysql/3307/data
[root@localhost ~]# mysql_install_db --user=mysql --datadir=/mysql/3308/data
```
准备配置文件
```
# 3306
[root@localhost ~]# vim /mysql/3306/etc/my.cnf
[mysqld]
port=3306
datadir=/mysql/3306/data
socket=/mysql/3306/socket/mysql.sock
log-error=/mysql/3306/log/mysql.log
pid-file=/mysql/3306/pid/mysql.pid
# 3307
[root@localhost ~]# sed 's/3306/3307/' /mysql/3306/etc/my.cnf > /mysql/3307/etc/my.cnf
# 3308
[root@localhost ~]# sed 's/3306/3308/' /mysql/3306/etc/my.cnf > /mysql/3308/etc/my.cnf
```
编写启动关闭脚本
```
[root@localhost ~]# vim /mysql/3306/bin/mysqld
#!/bin/bash
# date: 2021-05-12
# autho: xuanlv
port=3306
mysql_user="root"
mysql_pwd=""
cmd_path="/usr/bin"
mysql_basedir="/mysql"
mysql_sock="${mysql_basedir}/${port}/socket/mysql.sock"
start_mysql(){
if [ ! -e "$mysql_sock" ];then
printf "Starting MySQL...
"
${cmd_path}/mysqld_safe --defaults-file=${mysql_basedir}/${port}/etc/my.cnf &> /dev/null &
else
printf "MySQL is running...
"
exit
fi
}
stop_mysql(){
if [ ! -e "$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
}
restart_mysql(){
printf "Restarting MySQL...
"
stop_mysql
sleep 2
start_mysql
}
case $1 in
start)
start_mysql
;;
stop)
stop_mysql
;;
restart)
restart_mysql
;;
*)
printf "Usage: ${mysql_basedir}/${port}/bin/mysqld {start|stop|restart}
"
esac
```
授权
```
[root@localhost ~]# chmod +x /mysql/3306/bin/mysqld
```
拷贝成剩下两个实例启动脚本,记住3307,3308脚本端口一定要改
```
[root@localhost ~]# cp /mysql/3306/bin/mysqld /mysql/3307/bin/mysqld
[root@localhost ~]# cp /mysql/3306/bin/mysqld /mysql/3308/bin/mysqld
```
启动脚本
```
[root@localhost ~]# /mysql/3306/bin/mysqld start
[root@localhost ~]# /mysql/3307/bin/mysqld start
[root@localhost ~]# /mysql/3308/bin/mysqld start
```
查看端口3306,3307,3308
```
[root@localhost ~]# ss -tan
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 50 *:3306 *:*
LISTEN 0 50 *:3307 *:*
LISTEN 0 50 *:3308 *:*
LISTEN 0 128 *:22 *:*
```
测试登陆
```
[root@localhost ~]# mysql -h127.0.0.1 -P3307
Welcome to the MariaDB monitor. Commands end with ; or g.
Your MariaDB connection id is 1
Server version: 5.5.68-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)]>
```
查看当前端口
```
MariaDB [(none)]> show variables like 'port';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| port | 3307 |
+---------------+-------+
1 row in set (0.00 sec)
MariaDB [(none)]>
```
修改root密码
```
[root@localhost ~]# mysqladmin -uroot -S /mysql/3306/socket/mysql.sock password '123456'
[root@localhost ~]# mysqladmin -uroot -S /mysql/3307/socket/mysql.sock password '123456'
[root@localhost ~]# mysqladmin -uroot -S /mysql/3308/socket/mysql.sock password '123456'
```
测试修改的密码
```
[root@localhost ~]# mysql -uroot -h127.0.0.1 -P3306
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
[root@localhost ~]# mysql -uroot -h127.0.0.1 -p123456 -P3306
Welcome to the MariaDB monitor. Commands end with ; or g.
Your MariaDB connection id is 7
Server version: 5.5.68-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)]>
```
关闭mysql
```
[root@localhost ~]# /mysql/3306/bin/mysqld stop
[root@localhost ~]# /mysql/3307/bin/mysqld stop
[root@localhost ~]# /mysql/3308/bin/mysqld stop
```
目前使用的查看字符集
```
MariaDB [(none)]> show variables like 'charact%';
```
改字符集
```
[root@localhost ~]# vim /etc/my.cnf.d/mysql-clients.cnf
[mysql]
default-character-set=utf8mb4
```