[ovirt-users] migration

Dear all, I have a question. I know have my ovirt-engine running on a server on virtualbox. But I would like to add this server to my ovirt hypervisors pool. This OR I would like to update my current hypervisor (which is in centos 6.7) to centos 7 for the live snapshot removal support. (for taking backups) Is this possible *WITHOUT *losing my current vms. I only have 1 hypervisor at the moment, so migrating the VM's to another host isn't an option... Would this be possible with exporting the VMS to an export domain --> Full reinstall of the hypervisor --> import the VM's again from the export domain? (safely) Kind regards, Koen