I have a host that is Mac OS X 10.8 running Parallels 10.0.2. I have a guest that is also Mac OS X 10.8, created from the host recovery partition. Can I upgrade the guest to 10.9? If so, do I just choose the upgrade from the app store? For hardware, I'm on a 2009 Mac Pro Xeon if that matters.
You can, but you can always backup your VM (copy the.pvm) to a safe place before upgrading just for safety. You must have your reasons to keep the host in 10.8, but off the top of my head I don't see any reason not to upgrade the host also to 10.9.5, Mavericks is fairly mature now and in every sense better than ML in my opinion. Your hardware seems also to be fully 64 bit capable (64 bit EFI, CPU and GPU Drivers?).
Thanks for the reply. I agree on copying the .pvm. One of my previous Mac OS X upgrades went very poorly due to an obscure--but serious for me--problem that cost me a lot of time. Also, I rely on my computer to make a living. So combined with the above experience, it's generally a good idea to check out the next version of the op sys with my various tools and apps before making the plunge. Virtual Machines seem perfectly suited towards such a task.
You could also do a complete backup with TM, Super duper or Carbon Copy Cloner, and try the upgrade directly on the metal. But I agree VMs are a safe place for testing new software. Hope all goes well!
