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初始密码：

#vim  /var/log/mysqld.log

 A temporary password is generated for root:默认生成初始密码

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免密设置

#vim  /etc/my.cnf

skip-grant-tables

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需要手动增加可以远程访问数据库的用户。

方法一、本地登入mysql，更改 "mysql" 数据库里的 "user" 表里的 "host" 项，将"localhost"改为"%"

#mysql -u root -proot

mysql>use mysql; mysql>update user set host = '%' where user = 'root'; mysql>select host, user from user;

mysql>FLUSH PRIVILEGES ；

方法二、直接授权(推荐)

　　从任何主机上使用root用户，密码：youpassword（你的root密码）连接到mysql服务器：

# mysql -u root -proot 

mysql>GRANT ALL PRIVILEGES ON *.* TO  IDENTIFIED BY 'youpassword' WITH GRANT OPTION;

mysql>FLUSH PRIVILEGES ；

操作完后切记执行以下命令刷新权限 

FLUSH PRIVILEGES 

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http://www.cnblogs.com/ivictor/p/5142809.html

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修改密码

http://www.cnblogs.com/jyginger/archive/2011/04/27/2030017.html

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too many connections

1）临时修改

MariaDB [(none)]> show variables like "max_connections"; +-----------------+-------+ | Variable_name | Value | +-----------------+-------+ | max_connections | 214 | +-----------------+-------+ 1 row in set (0.00 sec) MariaDB [(none)]> set GLOBAL max_connections=1000;  Query OK, 0 rows affected (0.00 sec) MariaDB [(none)]> show variables like "max_connections"; +-----------------+-------+ | Variable_name | Value | +-----------------+-------+ | max_connections | 1000 | +-----------------+-------+ 1 row in set (0.00 sec)

 

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2018-05-05

ALTER USER 'root'@'localhost' IDENTIFIED BY 'root123';

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'root123';