2.9. Migrating a MySQL instance from a previous RHEL version to MySQL 8.4 on RHEL 10

Procedure

1. Install the mysql8.4-server package:

   # dnf install mysql8.4-server

2. Stop the service if it is already running:

   # systemctl stop mysqld.service

3. Copy the content of the /var/lib/mysql/ directory from the previous host to the same location on the RHEL 10 host.
4. Copy the configuration files from the previous host to the /etc/my.cnf.d/ directory, and ensure that the files includes only options valid for MySQL 8.4. For details, see the upstream documentation.

5. Restore the SELinux context:

   # restorecon -rv /var/lib/mysql/
   # restorecon -rv /etc/my.cnf.d/

6. Ensure the correct ownership of /var/lib/mysql/ and its subdirectories:

   # chown -R mysql:mysql /var/lib/mysql/

7. Enable and start the mysqld service:

   # systemctl enable --now mysqld.service

   When the service starts, MySQL automatically checks, repairs, and updates internal tables.