介绍在一台服务器上同时安装MySQL 5.6、5.7和8.0等3个版本等操作方法。
下载下面三个版本的通用安装包：
https://dev.mysql.com/get/Downloads/MySQL-8.0/mysql-8.0.27-linux-glibc2.12-x86_64.tar.xzhttps://downloads.mysql.com/archives/get/p/23/file/mysql-5.7.35-linux-glibc2.12-x86_64.tar.gzhttps://downloads.mysql.com/archives/get/p/23/file/mysql-5.6.51-linux-glibc2.12-x86_64.tar.gz
解压到/usr/local目录并创建软连接：
# cd /usr/local# tar xvf ~/mysql-5.7.35-linux-glibc2.12-x86_64.tar.gz # tar xvf ~/mysql-5.6.51-linux-glibc2.12-x86_64.tar.gz# tar xvf ~/mysql-8.0.27-linux-glibc2.12-x86_64.tar.xz# ln -s mysql-5.7.35-linux-glibc2.12-x86_64 mysql57# ln -s mysql-5.6.51-linux-glibc2.12-x86_64 mysql56# ln -s mysql-8.0.27-linux-glibc2.12-x86_64 mysql80
初始化数据：
# yum install -y perl# yum install -y autoconf# yum install -y libaio# mkdir -p /usr/local/mysql80/data# mysql80/bin/mysqld --initialize --user=mysql --datadir=/usr/local/mysql80/data# mysql57/bin/mysqld --initialize --user=mysql --datadir=/usr/local/mysql57/data# cd mysql56# scripts/mysql_install_db --user=mysql --datadir=/usr/local/mysql56/data
5.6初始化需要进入到mysql56目录下进行。
在数据初始化的过程中8.0和5.7会初始生成一个临时密码，5.6生成的是空密码，登录后修改密码。在5.6中修改密码的命令有所不同：
mysql> set password=password('yaoyuan');
编辑一个mysql的配置文件，/etc/my.cnf
[client]user=rootpassword=yaoyuan[mysql]prompt=(\\u@\\h) [\\d]>\\_[mysqld_multi]mysqld = /usr/local/mysql80/bin/mysqld_safe #启动时调用的命令mysqladmin = /usr/local/mysql80/bin/mysqladmin #关闭时调用的命令 下面需要提供用户和密码[mysqld56]mysqladmin = /usr/local/mysql56/bin/mysqladmin # 需要用5.6自己的关机命令basedir=/usr/local/mysql56socket = /tmp/mysql.sock56port = 3307datadir = /usr/local/mysql56/data[mysqld57]basedir=/usr/local/mysql57socket = /tmp/mysql.sock57port = 3308datadir = /usr/local/mysql57/data[mysqld80]basedir=/usr/local/mysql80socket = /tmp/mysql.sock80port = 3309datadir = /usr/local/mysql80/data
[mysqld_multi]下面要指定关闭用的用户名和密码，这个用户需要有shutdown的权限。也可以配置到[mysql]下面，如果配置到[mysqld_multi]下面需要把password改成pass，不然无法关机，这里官方文档错了。
MySQL 8.0的关机命令对MySQL 5.6不适用，会出错：
# /usr/local/mysql/bin/mysqladmin shutdown -S /tmp/mysql.sock56mysqladmin: shutdown failed; error: 'You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'shutdown' at line 1'
启动或关闭MySQL不同版本的进程，并检查状态：
[root@mysql_g bin]# mysqld_multi start 56,57,80[root@mysql_g bin]# mysqld_multi reportReporting MySQL serversMySQL server from group: mysqld56 is runningMySQL server from group: mysqld57 is runningMySQL server from group: mysqld80 is running[root@mysql_g ~]# ps -ef|grep mysqldroot 3181 1 0 02:49 pts/1 00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --basedir=/usr/local/mysql57 --socket=/tmp/mysql.sock57 --port=3308 --datadir=/usr/local/mysql57/datamysql 3300 3181 0 02:49 pts/1 00:00:01 /usr/local/mysql57/bin/mysqld --basedir=/usr/local/mysql57 --datadir=/usr/local/mysql57/data --plugin-dir=/usr/local/mysql57/lib/plugin --user=mysql --log-error=mysql_g.localdomain.err --pid-file=mysql_g.localdomain.pid --socket=/tmp/mysql.sock57 --port=3308root 3665 1 0 03:02 pts/1 00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --basedir=/usr/local/mysql56 --socket=/tmp/mysql.sock56 --port=3307 --datadir=/usr/local/mysql56/datamysql 3794 3665 0 03:02 pts/1 00:00:01 /usr/local/mysql56/bin/mysqld --basedir=/usr/local/mysql56 --datadir=/usr/local/mysql56/data --plugin-dir=/usr/local/mysql56/lib/plugin --user=mysql --log-error=mysql_g.localdomain.err --pid-file=mysql_g.localdomain.pid --socket=/tmp/mysql.sock56 --port=3307root 3851 1 0 03:11 pts/1 00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --basedir=/usr/local/mysql80 --socket=/tmp/mysql.sock80 --port=3309 --datadir=/usr/local/mysql80/datamysql 3970 3851 11 03:11 pts/1 00:00:01 /usr/local/mysql80/bin/mysqld --basedir=/usr/local/mysql80 --datadir=/usr/local/mysql80/data --plugin-dir=/usr/local/mysql80/lib/plugin --user=mysql --log-error=mysql_g.localdomain.err --pid-file=mysql_g.localdomain.pid --socket=/tmp/mysql.sock80 --port=3309root 4028 2966 0 03:11 pts/1 00:00:00 grep --color=auto mysqld[root@mysql_g ~]# mysqld_multi stop 57[root@mysql_g ~]# mysqld_multi reportReporting MySQL serversMySQL server from group: mysqld56 is runningMySQL server from group: mysqld57 is not runningMySQL server from group: mysqld80 is running
https://dev.mysql.com/get/Downloads/MySQL-8.0/mysql-8.0.27-linux-glibc2.12-x86_64.tar.xzhttps://downloads.mysql.com/archives/get/p/23/file/mysql-5.7.35-linux-glibc2.12-x86_64.tar.gzhttps://downloads.mysql.com/archives/get/p/23/file/mysql-5.6.51-linux-glibc2.12-x86_64.tar.gz
解压到/usr/local目录并创建软连接：
# cd /usr/local# tar xvf ~/mysql-5.7.35-linux-glibc2.12-x86_64.tar.gz # tar xvf ~/mysql-5.6.51-linux-glibc2.12-x86_64.tar.gz# tar xvf ~/mysql-8.0.27-linux-glibc2.12-x86_64.tar.xz# ln -s mysql-5.7.35-linux-glibc2.12-x86_64 mysql57# ln -s mysql-5.6.51-linux-glibc2.12-x86_64 mysql56# ln -s mysql-8.0.27-linux-glibc2.12-x86_64 mysql80
初始化数据：
# yum install -y perl# yum install -y autoconf# yum install -y libaio# mkdir -p /usr/local/mysql80/data# mysql80/bin/mysqld --initialize --user=mysql --datadir=/usr/local/mysql80/data# mysql57/bin/mysqld --initialize --user=mysql --datadir=/usr/local/mysql57/data# cd mysql56# scripts/mysql_install_db --user=mysql --datadir=/usr/local/mysql56/data
5.6初始化需要进入到mysql56目录下进行。
在数据初始化的过程中8.0和5.7会初始生成一个临时密码，5.6生成的是空密码，登录后修改密码。在5.6中修改密码的命令有所不同：
mysql> set password=password('yaoyuan');
编辑一个mysql的配置文件，/etc/my.cnf
[client]user=rootpassword=yaoyuan[mysql]prompt=(\\u@\\h) [\\d]>\\_[mysqld_multi]mysqld = /usr/local/mysql80/bin/mysqld_safe #启动时调用的命令mysqladmin = /usr/local/mysql80/bin/mysqladmin #关闭时调用的命令 下面需要提供用户和密码[mysqld56]mysqladmin = /usr/local/mysql56/bin/mysqladmin # 需要用5.6自己的关机命令basedir=/usr/local/mysql56socket = /tmp/mysql.sock56port = 3307datadir = /usr/local/mysql56/data[mysqld57]basedir=/usr/local/mysql57socket = /tmp/mysql.sock57port = 3308datadir = /usr/local/mysql57/data[mysqld80]basedir=/usr/local/mysql80socket = /tmp/mysql.sock80port = 3309datadir = /usr/local/mysql80/data
[mysqld_multi]下面要指定关闭用的用户名和密码，这个用户需要有shutdown的权限。也可以配置到[mysql]下面，如果配置到[mysqld_multi]下面需要把password改成pass，不然无法关机，这里官方文档错了。
MySQL 8.0的关机命令对MySQL 5.6不适用，会出错：
# /usr/local/mysql/bin/mysqladmin shutdown -S /tmp/mysql.sock56mysqladmin: shutdown failed; error: 'You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'shutdown' at line 1'
启动或关闭MySQL不同版本的进程，并检查状态：
[root@mysql_g bin]# mysqld_multi start 56,57,80[root@mysql_g bin]# mysqld_multi reportReporting MySQL serversMySQL server from group: mysqld56 is runningMySQL server from group: mysqld57 is runningMySQL server from group: mysqld80 is running[root@mysql_g ~]# ps -ef|grep mysqldroot 3181 1 0 02:49 pts/1 00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --basedir=/usr/local/mysql57 --socket=/tmp/mysql.sock57 --port=3308 --datadir=/usr/local/mysql57/datamysql 3300 3181 0 02:49 pts/1 00:00:01 /usr/local/mysql57/bin/mysqld --basedir=/usr/local/mysql57 --datadir=/usr/local/mysql57/data --plugin-dir=/usr/local/mysql57/lib/plugin --user=mysql --log-error=mysql_g.localdomain.err --pid-file=mysql_g.localdomain.pid --socket=/tmp/mysql.sock57 --port=3308root 3665 1 0 03:02 pts/1 00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --basedir=/usr/local/mysql56 --socket=/tmp/mysql.sock56 --port=3307 --datadir=/usr/local/mysql56/datamysql 3794 3665 0 03:02 pts/1 00:00:01 /usr/local/mysql56/bin/mysqld --basedir=/usr/local/mysql56 --datadir=/usr/local/mysql56/data --plugin-dir=/usr/local/mysql56/lib/plugin --user=mysql --log-error=mysql_g.localdomain.err --pid-file=mysql_g.localdomain.pid --socket=/tmp/mysql.sock56 --port=3307root 3851 1 0 03:11 pts/1 00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --basedir=/usr/local/mysql80 --socket=/tmp/mysql.sock80 --port=3309 --datadir=/usr/local/mysql80/datamysql 3970 3851 11 03:11 pts/1 00:00:01 /usr/local/mysql80/bin/mysqld --basedir=/usr/local/mysql80 --datadir=/usr/local/mysql80/data --plugin-dir=/usr/local/mysql80/lib/plugin --user=mysql --log-error=mysql_g.localdomain.err --pid-file=mysql_g.localdomain.pid --socket=/tmp/mysql.sock80 --port=3309root 4028 2966 0 03:11 pts/1 00:00:00 grep --color=auto mysqld[root@mysql_g ~]# mysqld_multi stop 57[root@mysql_g ~]# mysqld_multi reportReporting MySQL serversMySQL server from group: mysqld56 is runningMySQL server from group: mysqld57 is not runningMySQL server from group: mysqld80 is running
