Here are the steps to reset your MySQL root password on a Ubuntu server.
Step 1: Edit the file at /etc/mysql/my.cnf and add the following two lines to the end of the file.
[mysqld]
skip-grant-table
Step 2: Restart the MySQL server. The server will now skip over the password authentication.
sudo systemctl restart mysql.service
Step 3: Log in to MySQL server. Press enter when prompted for password. You should be able to login without password now.
mysql -u root -p
Enter password:
Step 4: Update the password of the root user.
update mysql.user set authentication_string = CONCAT('*', UPPER(SHA1(UNHEX(SHA1('yournewpasswordhere'))))) where user = 'root' and host = 'localhost';
Step 5: Exit MySQL, remove or comment away the two lines in /etc/mysql/mycnf, and restart the MySQL server.
sudo systemctl restart mysql.service
You should now be able to login to the MySQL server using your new password.
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