After upgrading to version 8.4.5 MySQL will throw database connection error in all sites

Symptoms

Sites are throwing a database error after an upgrade.

Description

The upstream MySQL package maintainers briefly had the "mysql-cloud" packages listed in the community repository, which caused the most recent updates to install this version of MySQL instead of the expected community version.

The "mysql-cloud" packages are for Oracle's MySQL Enterprise Edition, and are typically not available without a paid subscription through Oracle. The "mysql-cloud" packages mark the various "mysql-community" packages as "Obsolete", and thus overwrite these community packages as part of the update. The "mysql-cloud" version of MySQL is not supported by cPanel, as there are fundamental differences between "mysql-community" and "mysql-cloud" that cPanel does not accommodate for.

We've opened an internal case for our development team to investigate this further. For reference, the case number is CPANEL-46797. Follow this article to receive an email notification when a solution is published in the product.

Resolution

At this time MySQL has corrected the issue upstream, and the "mysql-cloud" packages are no longer listed; as such, any further upgrades to MySQL 8.4.5 will not experience this issue.

Workaround

For servers that have already had the incorrect "mysql-cloud" upgrade applied, the update that caused this will need to be rolled back to reinstall the correct "mysql-community" version back on the server; future updates will then work as expected.

1. Find the MySQL upgrade with yum history:

yum history

This will print a table of recent transactions by the package manager. To find the transaction where this upgrade occurred, you can check what was performed in each transaction with the following:

yum history info $ID

With $ID being the copied transaction.

2. Once the MySQL upgrade transaction is found, you can undo it with the following:

yum history undo $ID