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I encountered the problem of "Failed to start mysql.service: Unit mysql.service not found", which means that the system cannot find the MySQL service unit file, usually due to incorrect installation or the service name is incorrect. 1. First check whether MySQL is installed, use mysql --version to confirm, and reinstall if not installed; 2. Check whether the service name is mysqld or other variant, use the systemctl list-units or ls command to find it; 3. Confirm whether MariaDB is installed instead of MySQL, and check the mariadb service status; 4. Advanced users can try to manually create the mysql.service file and overload the systemd service. Following the above steps to check generally solves the problem.
If you encounter the problem "Failed to start mysql.service: Unit mysql.service not found", it means that the system cannot find the service unit file for MySQL, which usually means that MySQL is not installed correctly, or the service name is incorrect.

1. Confirm whether MySQL is actually installed
The most common reason for this problem is that MySQL is not installed successfully at all . You can check it by:

mysql --version
If command not found
is prompted, it means that MySQL is not installed. At this time, you need to reinstall the MySQL server. Take Ubuntu as an example:
sudo apt update sudo apt install mysql-server
After the installation is complete, try to start the service:

sudo systemctl start mysql
2. Confirm whether the service name is correct
Sometimes the service name is not what you expected. For example, in some Linux distributions, the service name of MySQL may be:
-
mysqld
(common in CentOS, RHEL) -
mysql@bootstrap
(if you are building a cluster or using group replication)
You can use the following command to find out which MySQL-related services are available in the system:
systemctl list-units | grep -i mysql
Or more thoroughly:
ls /etc/systemd/system/multi-user.target.wants/ | grep mysql
After finding the correct service name, replace the original command and start it, such as:
sudo systemctl start mysqld
3. Check whether MariaDB is installed instead of MySQL
Some distributions install MariaDB by default, rather than Oracle's official MySQL. MariaDB is a fork of MySQL, with good compatibility, but its service name is usually:
mariadb
If you find that the system prompts that mysql.service
cannot be found after installation, but it has indeed performed similar installation operations, you can try to check whether MariaDB is installed:
sudo systemctl status mariadb
If this is the case, you can enable and start the service in the following ways:
sudo systemctl enable mariadb sudo systemctl start mariadb
4. Manually create service files (advanced users)
If you are sure that MySQL has been installed but still cannot find the service, it may be that the service file is corrupt or missing. You can create a simple .service
file manually, for example:
sudo nano /etc/systemd/system/mysql.service
Then add the following content (adjust according to your actual path):
[Unit] Description=MySQL Database Server After=network.target [Service] User=mysql ExecStart=/usr/sbin/mysqld Restart=always [Install] WantedBy=multi-user.target
Reload systemd after saving:
sudo systemctl daemon-reexec sudo systemctl daemon-reload sudo systemctl enable mysql sudo systemctl start mysql
However, this step is recommended only if you understand the system structure, otherwise you should reinstall MySQL first.
Basically that's it. Although the problem seems scary, most of the cases are that the installation is incomplete or the service name is wrong. You can basically solve it by checking it in the above steps.
The above is the detailed content of How to fix 'Failed to start mysql.service: Unit mysql.service not found'. For more information, please follow other related articles on the PHP Chinese website!

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