I have a fairly stock three node HCI setup running oVirt 4.3.9. The hosts are oVirt node. I'm using GlusterFS storage for the self hosted engine and for some VMs. I also have some other VMs running from an external NFS storage domain.

Is it possible for me to upgrade this environment to 4.4 while keeping some of the VMs on GlusterFS storage domains running? Does the upgrade require an additional physical host? I'm reading through the upgrade guide and it's not very clear to me how the engine is reinstalled on CentOS8. Do you need a 4th host, or do you take one of the three existing hosts down, wipe it and install ovirt node 4.4?

Would it be easier for me to just move all VMs to my NFS storage domain, wipe all hosts and deploy a brand new 4.4 HCI cluster then import the NFS storage domain? Will the 4.3 VMs on the NFS storage domain import/run properly into the new 4.4 deployment or are there any other considerations?