This issue occurs if one or more of the active volumes/partitions are mounted on an unrecognized source volume manager or unrecognized device. Current versions of converter only recognize LVMs for volume managers. Any other volume manager is not recognized and likely results in a failure to clone any volume that is managed by the unrecognized manager component.
The same is true for devices that are not IDE or SCSI, such as multi-path devices and boot from SAN controllers that use a software layer to manage the volumes for boot from SAN configurations on physical systems.