2. Upgrade Warnings
2.1. PostgreSQL upgraded to 13 on Enterprise Linux 8
On Enterprise Linux 8 PostgreSQL is upgraded from 12 to 13, to match the version used on Enterprise Linux 9.
Users are required to change the DNF module, but the actual upgrade, including data migration, happens when the installer is executed for the first time.
During the upgrade a backup of the data is created in /var/lib/pgsql/data-old.
This backup can be removed once the upgrade is completed.