Now that Xen is slated for total removal from unRaid, it was time to seriously look at migrating to KVM. The easiest solution would probably have been to start from scratch and re-create all my VMs under KVM but that would require reactivating windows VMs, downloading all the updates, re-installing and re-configuring software etc.
The more attractive route was finding a way to migrate existing VMs from Xen to KVM. Thanks to jonp from LimeTech who published a how-to guide, this become fairly straightforward. I even recorded myself following the guide. Having done my Windows 7 VM, I then set about two Windows 8.1 systems and a Netrunner (ArchLinux / Manjaro) VM.
The Windows 8.1 migrations were as straightforward as the Win7 one had been. However, the Linux one just wouldn’t work for me. Once I’d set it up in KVM, pointed to the disk image and booted, I was greeted with a Grub error indicating that the root disk UUID could not be found. A quick check indicated that the UUID was in fact the same and no amount of Google Fu revealed a solution. I ended up re-installing the OS and dealing with a world of hurt in the updates (lot’s of conflicting dependencies).
So, with 4x VMs migrated, it was time to start playing with my shiny new KVM flavour of UnRaid. With a full weekend of playing around under my belt, I can now report that some things worked well, some didn’t. Some things I liked, some not so much;