What should I do before upgrading to MySQL 8.0?
We strongly recommend that you back up your databases before you upgrade your database or change to MariaDB. Make sure that you have at least one valid cPanel backup for each of the accounts, and a system backup.
Please take a look at the following article which contains a list of resources on backing up your databases before an upgrade:
How do I backup MySQL databases prior to upgrading to a new version?
In the MySQL/MariaDB Upgrade interface, select MySQL 8.0, then select Continue. Click "Run checker" under "MySQL Upgrade Checker via MySQLShell". This downloads a package called "mysql-shell" and verifies whether your MySQL 5.7 server is ready for an upgrade to MySQL 8.
You must address any errors and review the process's output, including warnings before proceeding to upgrade to MySQL 8.0 to avoid a failed upgrade. Please also review MySQL's Reference Manual: Preparing Your Installation for Upgrade
Please note that running the "Upgrade Checker" before upgrading to MySQL 8.0 is very important. If errors exist in your databases that would have been caught and potentially fixed by the checker, it will be too late once the upgrade has started. cPanel does not support downgrading MySQL versions, but if an error occurs during the upgrade, sometimes, that is the only solution.
If you're unsure of how to proceed with addressing the issues found by the upgrade checker, you may benefit from contacting a system administrator for further investigation. If you do not have such an administrator, you may search for one in our listings here:
System Administration Services
However, please note that cPanel, LLC does not endorse or recommend any particular provider on that list, nor can we be held liable for any services performed by third-party providers, including those on the list.