I have a lab with an environment based on 4.4.8.6-1, with 3 CentOS Linux 8.4 hosts and a CentOS 8.4 external engine system (that is a VM on vSphere, so that I can leverage a snapshot methodology for the process...).

I would like to pass to 4.4.9 and retain a full plain OS on hosts for the moment, without going through oVirt nodes, but standing the repo problems and CentOS 8.x going through EOL this is what I'm planning to do:

1. stop engine service on engine system

2. convert engine to CentOS Stream

This step needs some confirmation.

Could you provide an official link about the process?

I'm not able to find it again. Is it a problem of mine or all (CentOS website, RHEL website) seem to point only to conversion from CentOS Linux to RHEL??

Apart external websites provided workflows, I was only able to find a mid January youtube video, when CentOS was based on 8.3, with these steps:

yum install centos-release-stream
yum swap centos-{linux,stream}-repos
yum repolist
yum distro-sync
reboot

The video link is here:

https://www.youtube.com/watch?v=Ba2ytp_8x7s

No mention at

https://www.redhat.com/en/blog/faq-centos-stream-updates

And on CentOS page I only found this:

https://centos.org/distro-faq/

with Q7 containing only the two instructions:

dnf swap centos-linux-repos centos-stream-repos
dnf distro-sync

What to use safely?

Is it possible to include some sort of documentation or links on oVirt page, to migrate from CentOS Linux to CentOS Stream for oVirt upgrade purposes?

3. After reboot implied, I think, in step 2., use the usual steps to update engine to 4.4.9

4. update the first out of three hosts from CentOS Linux to CentOS Stream and to 4.4.9.

4.a follow the same approach of engine (when defined) and pass it to Stream retaining the 4.4.8.

4.b upgrade from the web admin gui to 4.4.9

5. Do the same for second host and third hosts

Any hints, comments, limitations in having mixed 4.4.8 and 4.4.9 hosts for a while and such?

Thanks,

Gianluca