The oVirt Team has just released a new version of ovirt-engine package that
fixes upgrade related issues..
We recommend to users experiencing upgrade issues to try again with this
 Bug 1609839 - Foreign key constraint violation on upgrade to 4.2.5
 Bug 1613168 - On rollback of failed upgrade from 4.2.1+, engine-setup
outputs errors about the uuid-ossp extension
MANAGER, SOFTWARE ENGINEERING, EMEA R&D RHV
Red Hat EMEA <https://www.redhat.com/>