1. Confirm MySQL version
Firstly, you must confirm which version of MySQL on Ubuntu you are running as commands will be different.
mysql -V
If on MySQL version 8, you will see something like:
mysql Ver 8.0.20-0ubuntu0.20.04.1 for Linux on x86_64 ((Ubuntu))
If you are on MySQL version 5, you will see something similar to:
mysql Ver 14.14 Distrib 5.7.36, for Linux (x86_64) using EditLine wrapper
2. Restart MySQL with skip-grant-table
In order to skip the grant tables and reset the root password, we must first stop the MySQL service. Enter your Linux password if prompted.
sudo /etc/init.d/mysql stop
Ensure the directory /var/run/mysqld exists and correct owner set.
sudo mkdir /var/run/mysqld
sudo chown mysql /var/run/mysqld
Now start MySQL with the --skip-grant-tables option. The & is required here.
sudo mysqld_safe --skip-grant-tables&
You should see something similar:
[1] 1283
user@server:~$ 2019-02-12T11:15:59.872516Z mysqld_safe Logging to syslog.
2019-02-12T11:15:59.879527Z mysqld_safe Logging to '/var/log/mysql/error.log'.
2019-02-12T11:15:59.922502Z mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
Now press ENTER to return to the Linux BASH prompt.
3. Change MySQL Root Password
You can now log in to the MySQL root account without a password.
sudo mysql --user=root mysql
Save
Once logged in, you will see the mysql> prompt.
MySQL 8 – Reset Root Password
For MySQL 8 on Ubuntu, run following commands.
UPDATE mysql.user SET authentication_string=null WHERE User='root';
flush privileges;
Replace your_password_here with your own. (Generate a strong password here)
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'your_password_here';
Flush privileges again.
flush privileges;
Exit MySQL.
exit
4. Test New Root Password
Make sure all MySQL processes are stopped before starting the service again.
sudo killall -u mysql
If you see a message similar to below, press ENTER to continue.
2020-05-30T07:23:38.547616Z mysqld_safe mysqld from pid file /var/lib/mysql/ubuntu.pid ended
Start MySQL again.
sudo /etc/init.d/mysql start
Log in to MySQL again and you should now be prompted for a password.
sudo mysql -p -u root
Enter your MySQL root password. If correct, you should see something like:
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 8
Server version: 8.0.20-0ubuntu0.20.04.1 (Ubuntu)
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