Centos6.5 重置mysql密码，并设置允许远程连接

gwdsqw

root密码忘记，重置mysql的root密码：  一、修改mysql的配置文件my.cnf
  1.在[mysqld]的段中加上一句：skip-grant-tables
  [mysqld]   
datadir=/var/lib/mysql   
socket=/var/lib/mysql/mysql.sock   
skip-name-resolve   
skip-grant-tables   
保存并且退出vi。
  （或执行 mysqld_safe --skip-grant-tables &）
  2.重新启动mysqld   
# /etc/init.d/mysqld restart   
Stopping MySQL: [ OK ]   
Starting MySQL: [ OK ]
     
3.登录并修改MySQL的root密码   
# /usr/bin/mysql   
Welcome to the MySQL monitor. Commands end with ; or \g.   
Your MySQL connection id is 3 to server version: 3.23.56   
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
  mysql> use mysql ;   
Reading table information for completion of table and column names   
You can turn off this feature to get a quicker startup with -A
  Database changed   
mysql> UPDATE user SET Password = password ( 'new-password' ) WHERE User = 'root' ;   
Query OK, 0 rows affected (0.00 sec)   
Rows matched: 2 Changed: 0 Warnings: 0
  mysql> flush privileges ;   
Query OK, 0 rows affected (0.01 sec)
  mysql> quit   
Bye   
4.将MySQL的登录设置修改回来   
# vi /etc/my.cnf   
将刚才在[mysqld]的段中加上的skip-grant-tables删除   
保存并且退出vi。
  5．重新启动mysqld   
# /etc/init.d/mysqld restart   
Stopping MySQL: [ OK ]   
Starting MySQL: [ OK ]
     
二、
  停止mysql服务
  /etc/init.d/mysqld stop
  sudo mysqld_safe --skip-grant-table&
  mysql
  use mysql;
  update user set password = password('yourpasswd') where user = 'root';
  flush privileges;
  重启下mysql服务即可重新用新密码登录
  /etc/init.d/mysqld restart
     
允许远程连接mysql
  通过navicat连接MySQL的时候发生的这个错误   
ERROR 1130: Host ***.***.***.*** is not allowed to connect to this MySQL server     
说明所连接的用户帐号没有远程连接的权限，只能在本机(localhost)登录。     
需更改 MySQL 数据库里的 user表里的 host项     
把localhost改称%
  一、
  登陆到MySQL ，首先 use MySQL；   
按照别人提供的方式update的时候，出现错误。     
MySQL> update user set host='%' where user = 'root';     
ERROR 1062 (23000): Duplicate entry '%-root' for key 'PRIMARY'   
然后查看了下数据库的host信息如下：     
MySQL> select host from user where user = 'root';     
+-----------------------+     
| host |     
+-----------------------+     
| % |     
| 127.0.0.1 |     
| localhost.localdomain |     
+-----------------------+     
3 rows in set (0.00 sec)     
host已经有了%这个值，所以直接运行命令：
  MySQL>flush privileges;
     
二、
  mysql> grant all privileges on *.* to 'root'@'%' withgrant option;
  Query OK, 0 rows affected (0.02 sec)
     
mysql> flush privileges;
  Query OK, 0 rows affected (0.00 sec)
     
mysql> selectuser.host from user;
  +-----------+--------------+
  | user| host|
  +-----------+--------------+
  | root| %|
  | root| 127.0.0.1|
  | repl_user | 192.168.1.52 |
  +-----------+--------------+
  3 rows in set (0.00 sec)
  允许指定IP访问mysql
  mysql> grant all privileges on *.* to 'root'@***.***.***.****  identified by '123456';   
QueryOK, 0 rows affected (0.00 sec)