一个Mysql（5.5版本）设置多个端口运行多个实例。搞了一天，终于弄好，先备忘一下！
一、设置mysqld_multi
复制一份my.cnf，重命名为my_multi.cnf
修改my_multi.cnf，主要配置项目如下
[mysqld_multi] mysqld = /usr/bin/mysqld_safe mysqladmin = /usr/bin/mysqladmin user = root password = 123 #默认的3306端口 [mysqld6] user = mysql pid-file = /var/run/mysqld/mysqld.pid socket = /var/run/mysqld/mysqld.sock port = 3306 basedir = /usr datadir = /var/lib/mysql tmpdir = /tmp #加一个3308的端口 [mysqld8] user = mysql pid-file = /var/run/mysqld/mysqld8.pid socket = /var/run/mysqld/mysqld8.sock port = 3308 basedir = /usr datadir = /var/lib/mysql8 tmpdir = /tmp
二、创建3308端口的数据存储目录
mkdir /var/lib/mysql8 chown mysql:mysql /var/lib/mysql8
三、修改文件/etc/apparmor.d/usr.sbin.mysqld
修改完成后重启：/etc/init.d/apparmor restart
/usr/sbin/mysqld {
#include <abstractions/base>
#include <abstractions/nameservice>
#include <abstractions/user-tmp>
#include <abstractions/mysql>
#include <abstractions/winbind>
capability dac_override,
capability sys_resource,
capability setgid,
capability setuid,
network tcp,
/etc/hosts.allow r,
/etc/hosts.deny r,
/etc/mysql/*.pem r,
/etc/mysql/conf.d/ r,
/etc/mysql/conf.d/* r,
/etc/mysql/*.cnf r,
/usr/lib/mysql/plugin/ r,
/usr/lib/mysql/plugin/*.so* mr,
/usr/sbin/mysqld mr,
/usr/share/mysql/** r,
/var/log/mysql.log rw,
/var/log/mysql.err rw,
/var/lib/mysql/ r,
/var/lib/mysql/** rwk,
/var/log/mysql/ r,
/var/log/mysql/* rw,
/var/run/mysqld/mysqld.pid rw,
/var/run/mysqld/mysqld.sock w,
/run/mysqld/mysqld.pid rw,
/run/mysqld/mysqld.sock w,
#####主要是添加这些读写权限信息，不然后期会报一些莫名的错误
/var/lib/mysql8/ r,
/var/lib/mysql8/** rwk,
/var/run/mysqld/mysqld8.pid rw,
/var/run/mysqld/mysqld8.sock w,
/run/mysqld/mysqld8.pid rw,
/run/mysqld/mysqld8.sock w,
/sys/devices/system/cpu/ r,
# Site-specific additions and overrides. See local/README for details.
#include <local/usr.sbin.mysqld>
}
四、初始化数据库
mysql_install_db --user=mysql --datadir=/var/lib/mysql8 &
五、重新数据库（默认打开3306商品的数据库）
service mysql restart
六、打开新设置端口的数据库
mysqld_multi --defaults-file=/etc/mysql/my_multi.cnf start 8
七、完事，可以查看下了
netstat -ntlp
终于看到可喜的结果如下！
tcp 0 0 127.0.0.1:3306 0.0.0.0:* LISTEN 1402/mysqld tcp 0 0 127.0.0.1:3308 0.0.0.0:* LISTEN 2202/mysqld
原文：http://my.oschina.net/u/181786/blog/473779