我分享一步一步的最终解决方案，重置MySQL密码在Linux Ubuntu。

参考来自博客(dbrnd.com)

步骤1: 停止MySQL服务。

sudo stop mysql

步骤2: 关闭所有运行mysqld。

sudo killall -9 mysqld

步骤3: 以安全模式启动mysqld。

sudo mysqld_safe --skip-grant-tables --skip-networking &

步骤4: 启动mysql客户端

mysql -u root

步骤5: 登录成功后，如果需要修改密码，请执行该命令。

FLUSH PRIVILEGES;

步骤6: 您可以更新mysql root密码。

UPDATE mysql.user SET Password=PASSWORD('newpwd') WHERE User='root';

注意:在MySQL 5.7中，Password列被称为authentication_string。

第七步: 请执行该命令。

FLUSH PRIVILEGES;

正如mysql文档中password()函数所说:

此函数在MySQL 8.0.11中被移除。

这将使mysql v8.0.11及更新版本的所有现有答案都失效。

根据mysql文档，重置root密码的新通用方法如下:

The preceding sections provide password-resetting instructions specifically for Windows and Unix and Unix-like systems. Alternatively, on any platform, you can reset the password using the mysql client (but this approach is less secure): Stop the MySQL server if necessary, then restart it with the --skip-grant-tables option. This enables anyone to connect without a password and with all privileges, and disables account-management statements such as ALTER USER and SET PASSWORD. Because this is insecure, if the server is started with the --skip-grant-tables option, it enables --skip-networking automatically to prevent remote connections. Connect to the MySQL server using the mysql client; no password is necessary because the server was started with --skip-grant-tables: shell> mysql In the mysql client, tell the server to reload the grant tables so that account-management statements work: mysql> FLUSH PRIVILEGES; Then change the 'root'@'localhost' account password. Replace the password with the password that you want to use. To change the password for a root account with a different host name part, modify the instructions to use that host name. mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass'; You should now be able to connect to the MySQL server as root using the new password. Stop the server and restart it normally (without the --skip-grant-tables and --skip-networking options).

如果你想修改MySQL root密码，在终端输入:

Sudo dpkg-reconfigure mysql-server-5.5

MySQL守护进程将被停止，并提示您输入新密码。

首先执行以下命令:

sudo mysql

然后你应该检查你的MySQL用户帐户使用的身份验证方法。运行这个命令

SELECT user,authentication_string,plugin,host FROM mysql.user;

现在你可以看到这样的东西:

+------------------+-------------------------------------------+-----------------------+-----------+
| user             | authentication_string                     | plugin                | host      |
+------------------+-------------------------------------------+-----------------------+-----------+
| root             |                                           | auth_socket           | localhost |
| mysql.session    | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE | mysql_native_password | localhost |
| mysql.sys        | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE | mysql_native_password | localhost |
| debian-sys-maint | *CC744277A401A7D25BE1CA89AFF17BF607F876FF | mysql_native_password | localhost |
+------------------+-------------------------------------------+-----------------------+-----------+

在上面的表格中，你可以看到你所有的mysql用户的帐户状态&如果你已经设置了root帐户的密码，然后在插件列中看到mysql_native_password而不是auth_socket。 总之，要更改root密码，您应该运行以下命令:

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

请务必将密码更改为您选择的强密码。 然后重新加载你的服务器，把你的新变化生效运行这个;

FLUSH PRIVILEGES;

所以再次检查你的mysql所使用的认证方法，通过下面的命令:

SELECT user,authentication_string,plugin,host FROM mysql.user;

现在输出是:

+------------------+-------------------------------------------+-----------------------+-----------+
| user             | authentication_string                     | plugin                | host      |
+------------------+-------------------------------------------+-----------------------+-----------+
| root             | *3636DACC8616D997782ADD0839F92C1571D6D78F | mysql_native_password | localhost |
| mysql.session    | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE | mysql_native_password | localhost |
| mysql.sys        | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE | mysql_native_password | localhost |
| debian-sys-maint | *CC744277A401A7D25BE1CA89AFF17BF607F876FF | mysql_native_password | localhost |
+------------------+-------------------------------------------+-----------------------+-----------+

正如您在授权表中看到的，您的根帐户具有mysql_native_password ． 现在你可以退出MYSQL shell了

exit;

就是这样。只是你应该通过sudo service mysql restart重新启动mysql。 现在你可以用root帐号和密码轻松登录mysql。

I had to go this route on Ubuntu 16.04.1 LTS. It is somewhat of a mix of some of the other answers above - but none of them helped. I spent an hour or more trying all other suggestions from MySql website to everything on SO, I finally got it working with: Note: while it showed Enter password for user root, I didnt have the original password so I just entered the same password to be used as the new password. Note: there was no /var/log/mysqld.log only /var/log/mysql/error.log Also note this did not work for me: sudo dpkg-reconfigure mysql-server-5.7 Nor did: sudo dpkg-reconfigure --force mysql-server-5.5 Make MySQL service directory. sudo mkdir /var/run/mysqld Give MySQL user permission to write to the service directory. sudo chown mysql: /var/run/mysqld Then:

kill the current mysqld pid run mysqld with sudo /usr/sbin/mysqld & run /usr/bin/mysql_secure_installation Output from mysql_secure_installation root@myServer:~# /usr/bin/mysql_secure_installation Securing the MySQL server deployment. Enter password for user root: VALIDATE PASSWORD PLUGIN can be used to test passwords and improve security. It checks the strength of password and allows the users to set only those passwords which are secure enough. Would you like to setup VALIDATE PASSWORD plugin? Press y|Y for Yes, any other key for No: no Using existing password for root. Change the password for root ? ((Press y|Y for Yes, any other key for No) : y New password: Re-enter new password: By default, a MySQL installation has an anonymous user, allowing anyone to log into MySQL without having to have a user account created for them. This is intended only for testing, and to make the installation go a bit smoother. You should remove them before moving into a production environment. Remove anonymous users? (Press y|Y for Yes, any other key for No) : y Success. Normally, root should only be allowed to connect from 'localhost'. This ensures that someone cannot guess at the root password from the network. Disallow root login remotely? (Press y|Y for Yes, any other key for No) : y Success. By default, MySQL comes with a database named 'test' that anyone can access. This is also intended only for testing, and should be removed before moving into a production environment. Remove test database and access to it? (Press y|Y for Yes, any other key for No) : y Dropping test database... Success. Removing privileges on test database... Success. Reloading the privilege tables will ensure that all changes made so far will take effect immediately. Reload privilege tables now? (Press y|Y for Yes, any other key for No) : y Success. All done!

当你在你想要更改密码的系统上使用MySQL的PASSWORD()时，它可能会导致密码在MySQL日志中以cleartext [source]显示。对我来说，让它们和备份等像密码一样安全听起来像是噩梦，所以我喜欢这样做:

On your local machine, run this with your password: mysql -u someuser -p < <(echo "SELECT PASSWORD('mypass');") Note the space in front to prevent it from turning up in the bash history (for other distros than Ubuntu, this might work differently – source). On your server machine, execute the following command to change its MySQL root password (replace myhash with your password's hash as printed by the first command): mysql -u root -p < <(echo "SET PASSWORD FOR root@localhost = 'myhash';") Optionally, let's be a bit paranoid: On your local machine, clear your terminal screen with clear and purge your virtual terminal scrollback, to hide the cleartext password appearing in the command above.