1.起初装上CentOS7后，mysql数据库变为Mariadb数据库。但实际是还是mysql.
2.用户远程连接该数据库发现连接不了。然后关了SElinux，挺了firewall，发现还是不行。
3.查阅资料终于解决：
A.默认root是没有密码的，插入host数据 %，修改密码：
$ mysql -u root mysql> use mysql; mysql> INSERT INTO user(host,user,password) VALUES(‘%‘,‘root‘,‘‘); mysql> UPDATE user SET Password = PASSWORD(‘newpass‘) WHERE user = ‘root‘; mysql> FLUSH PRIVILEGES;
使用 slect host,user,password from user; 结果如下：
Database changed MariaDB [mysql]> update user set password = password(‘cosmysql‘) where user=‘root‘; Query OK, 3 rows affected (0.01 sec) Rows matched: 5 Changed: 3 Warnings: 0 MariaDB [mysql]> flush privileges; Query OK, 0 rows affected (0.00 sec) MariaDB [mysql]> select host,user,password from user; +-----------------------+------+-------------------------------------------+ | host | user | password | +-----------------------+------+-------------------------------------------+ | localhost | root | *F2A7750541679FE9A1CC3ABD453EFC346084637C | | localhost.localdomain | root | *F2A7750541679FE9A1CC3ABD453EFC346084637C | | 127.0.0.1 | root | *F2A7750541679FE9A1CC3ABD453EFC346084637C | | ::1 | root | *F2A7750541679FE9A1CC3ABD453EFC346084637C | | localhost | | | | localhost.localdomain | | | | % | root | *F2A7750541679FE9A1CC3ABD453EFC346084637C | +-----------------------+------+-------------------------------------------+ 7 rows in set (0.00 sec)
B.授权，否则会报 Access denied for user ‘root‘@‘%‘ to database ‘xxx‘ 的错
grant all on xxxx.* to ‘root‘@‘%‘ identified by ‘password‘ with grant option;
xxxx代表创建的数据库;这里的xxxx为mysql,你也可以用*代替xxxx.那样远程登陆就会拥有全部数据库的访问权限.
password为用户密码，在此为root的密码
2015年10月18日20:48:53
原文：http://www.cnblogs.com/xccnblogs/p/4890240.html