一、环境规划

1.端口 :

3307,3308,3309

2.数据存储路径 :

/data/330{7..9}/data

3.配置文件主信息:

/data/330{7..9}/my.cnf
port=3307/3308/3309
server_id=7/8/9
datadir=/data/330{7..9}/data
ocket=/tmp/mysql330{7..9}.sock

二、 搭建部署

1. 创建关键目录并授权

mkdir -p /data/330{7..9}/data 
chown -R mysql.mysql /data/*

2.初始化数据

mysqld --initialize-insecure --user=mysql --basedir=/usr/local/mysql --datadir=/data/3307/data  
mysqld --initialize-insecure --user=mysql --basedir=/usr/local/mysql --datadir=/data/3308/data  
mysqld --initialize-insecure --user=mysql --basedir=/usr/local/mysql --datadir=/data/3309/data  

补充：若在搭建多实例前，服务器本身存在一台MySQL数据库，则需先将本有数据库关闭，并将默认配置文件my.cnf文件存放位置迁移，多实例创建完成后再将其迁回，并重启原有数据库

mv /etc/my.cnf  /tmp

3.准备配置文件

cat > /data/3307/my.cnf <<EOF
[mysqld]
user=mysql
basedir=/usr/local/mysql
datadir=/data/3307/data
port=3307
server_id=7
socket=/tmp/mysql3307.sock
EOF

cat > /data/3308/my.cnf <<EOF
[mysqld]
user=mysql
basedir=/server/tools/mysql
datadir=/data/3308/data
port=3308
server_id=8
socket=/tmp/mysql3308.sock
EOF

cat > /data/3309/my.cnf <<EOF
[mysqld]
user=mysql
basedir=/usr/local/mysql
datadir=/data/3309/data
port=3309
server_id=9
socket=/tmp/mysql3309.sock
EOF

4.准备启动脚本

cat > /etc/systemd/system/mysqld3307.service <<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/usr/local/mysql/bin/mysqld --defaults-file=/data/3307/my.cnf
LimitNOFILE = 5000
EOF

cat > /etc/systemd/system/mysqld3308.service <<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/usr/local/mysql/bin/mysqld --defaults-file=/data/3308/my.cnf
LimitNOFILE = 5000
EOF

cat > /etc/systemd/system/mysqld3309.service <<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/usr/local/mysql/bin/mysqld --defaults-file=/data/3309/my.cnf
LimitNOFILE = 5000
EOF

5.启动多实例

systemctl start mysqld3307
systemctl start mysqld3308
systemctl start mysqld3309

检查是否启动

netstat -tulnp|grep mysqld
tcp6       0      0 :::3307                 :::*                    LISTEN      10327/mysqld        
tcp6       0      0 :::3308                 :::*                    LISTEN      10361/mysqld        
tcp6       0      0 :::3309                 :::*                    LISTEN      10395/mysqld   

6.登录数据库

mysql -S /tmp/mysql3307.sock
mysql -S /tmp/mysql3308.sock
mysql -S /tmp/mysql3309.sock

说明：使用多实例登陆到不同的数据库时，一定要指定该数据库的本地socket文件路径