This option relevant only for the upgrade from 3.6 to 4.0(engine had
different OS major versions), it all other cases the upgrade flow very
similar to upgrade flow of standard engine environment.
1. Put hosted-engine environment to GlobalMaintenance(you can do it via
UI)
2. Update engine packages(# yum update -y)
3. Run engine-setup
4. Disable GlobalMaintenance
Could someone explain me at least what "Cluster PROD is at version 4.2 which
is not supported by this upgrade flow. Please fix it before upgrading."
means ? As far as I know 4.2 is the most recent branch available, isn't it ?
I have no idea where did you get
"Cluster PROD is at version 4.2 which is not supported by this upgrade flow. Please
fix it before upgrading."
Please do not cut output and provide exact one.
IIUC you should do 'yum update ovirt\*setup\*' and then 'engine-setup'
and only after it would finish successfully you would do 'yum -y update'.
Maybe that's your problem?
Jiri