重置密码和数据库（适合源码安装，rpm的可能不行）
[root@mail postfixadmin]# /usr/bin/mysql_install_db --force
Installing all prepared tables
Fill help tables
To start mysqld at boot time you have to copy support-files/mysql.server
to the right place for your system
PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:
/usr/bin/mysqladmin -u root password 'new-password'
/usr/bin/mysqladmin -u root -h mail.test.com password 'new-password'
See the manual for more instructions.
NOTE: If you are upgrading from a MySQL <= 3.22.10 you should run
the /usr/bin/mysql_fix_privilege_tables. Otherwise you will not be
able to use the new GRANT command!
You can start the MySQL daemon with:
cd /usr ; /usr/bin/mysqld_safe &
You can test the MySQL daemon with the benchmarks in the 'sql-bench' directory:
cd sql-bench ; perl run-all-tests
Please report any problems with the /usr/bin/mysqlbug script!
2. cp support-files/mysql.server /etc/init.d/mysql（源码路径）
3 ./usr/bin/mysqld_safe &
4./etc/init.d/mysql start
5 mysqladmin -u root password "new password"
解决root关于本机登陆可以，远程同样密码帐户无法用mysql administrator连接
在使用MySQL-Front连接mysql的时候发生的这个错误
ERROR 1130: Host 192.168.88.160 is not allowed to connect to this MySQL server
1。 改表法。可能是你的帐号不允许从远程登陆，只能在localhost。这个时候只要在localhost的那台
电脑，登入mysql后，更改 “mysql” 数据库里的 “user” 表里的 “host” 项，从”localhost”改称”%”
mysql -u root -p
mysql>use mysql;
mysql>update user set host = ‘%’ where user =’root’;
mysql>flush privileges;
mysql>select ‘host’,'user’ from user where user=’root’;
现在就可以连接了！
2. 授权法。例如，你想myuser使用mypassword从任何主机连接到mysql服务器的话。
GRANT ALL PRIVILEGES ON *.* TO
‘myuser’@'%’IDENTIFIED BY ‘mypassword’ WITH GRANT OPTION;
如果你想允许用户myuser从ip为192.168.1.3的主机连接到mysql服务器，并使用mypassword作为密码
本文转自 pgmia 51CTO博客，原文链接:http://blog.51cto.com/heyiyi/112959
