I was trying to run SpinRite 6.1 on some drives from an old Drobo 5N NAS that bit the dust a few years back, but I didn’t have an x86 machine handy, so after a bit of research I found a very elegant way to do this with QEMU on macOS.
Allow me to provide a little more background for those who may not know what I’m talking about…
In my opinion, Steve Gibson’s SpinRite is the best hard drive maintenance and recovery utility out there, and the way you use it is by booting it from removable media (typically, a USB thumb drive, although in the distant past I remember running it off these things we call “CD’s”). The SpinRite program itself runs using FreeDOS.
As time has progressed, though, machines have moved to UEFI booting instead of BIOS, and on top of that many machines have moved away from x86 architectures to ARM architectures, like Apple Silicon on macs, and now increasingly, ARM on Windows, and given that SpinRite needs legacy BIOS boot methods and an x86 chipset to run, it’s becoming more challenging to get it going these days.
We’re looking at getting a new NAS in place at our house in the near future, and I had old drives from a prior NAS (a Drobo 5N that ceased to function several years back) which I wanted to dust off and run through SpinRite in anticipation of using them in a new NAS.
I recently did a purge of old devices and I no longer had an Intel/AMD x86/x64 machine handy anymore, and short of getting a small Intel compute stick or something, I wanted to see if I could somehow emulate what was necessary to have SpinRite 6.1 run on my M2 MacBook Pro.
After a little while of research and some back and forth with ChatGPT, I found the solution in the form of QEMU, which I installed via Homebrew:
brew install qemu
(I also looked at UTM which is another great app that wraps QEMU with a nice UI, but due to
some quirks on macOS – primarily the fact that you can’t run it elevated with sudo to get the proper drive access
since the app doesn’t work properly that way – I had to pivot.)
Now, in order to get a SpinRite 6.1 ISO file in the proper format for use with QEMU, I did have to temporarily boot up Windows 11 in Parallels and run spinrite.exe to create that image (BUT, see next, you don’t need to do this, there’s a simpler way to do this). This ISO conversion was just a one-time exercise, as I have the ISO stored in my OneDrive for later use.
However, for purposes of this blog post, I didn’t want folks to have to go through setting up a full Windows VM one time just to do the .img to .iso conversion, and though I tried several mac-native commands to try to get the conversion just right, none of them worked specifically for SpinRite.
So, I resorted to installing Wine via Homebrew and using
that to run spinrite.exe to prove out creating the ISO in a less heavy way that doesn’t involve running a full
Windows 11 VM. (Note that Wine is one of those apps that macOS is going to initially block for “safety” reasons, but
since you hopefully know what you’re doing, you can go to Privacy & Security in Settings and click “Open anyway.”)
brew install wine-stable
wine spinrite.exe # Opens the SpinRite GUI app and lets you make an ISO; close once done
Before you go fire up your QEMU emulator, first you should insert your storage media you’re going to run SpinRite on,
then eject it through Finder, but leave the physical drive inserted – yes, it needs to be not mounted to the host
macOS operating system so that QEMU can attach to it. (Alternatively you can do diskutil list to see what your disk
number is – in my case it was /dev/disk4 – then do diskutil unmount /dev/disk4 to unmount it.) If you forget to do
this, QEMU will say qemu-system-x86_64: Could not open '/dev/disk4': Resource busy. Also note that after quitting
QEMU, macOS will immediately re-mount the drive…
Finally, run QEMU (with sudo, which is necessary so it can get at the drive – as always do this with caution and only
if you’re comfortable), providing the correct path to SpinRite.iso. Note that the ISO path is case-sensitive –
beyond the obviousness of macOS being a case-sensitive file system, I say this because spinrite.exe will output
SpinRite.iso with uppercase S and R, and that might trip someone up.
sudo qemu-system-x86_64 -drive file=/dev/disk4,format=raw -cdrom /Users/username/Desktop/SpinRite.iso -boot d
Voilà:
Hopefully, this saves someone out there some time from having to go through the same steps I did to figure this out.
As a caveat, if it wasn’t obvious, this solution does not work against your actual hard drive of your mac itself, but it at least is a good middle ground for servicing other drives that you may have.
As another caveat, SpinRite 6.1 may give a new message (as of the 6.1 version) about an inability to create an SRLOGS
directory and write to it – I suspect that is due to the way it is being launched from a bootable read-only ISO image
which is presented to the guest OS as a CD-ROM, and unlike a bootable USB drive, it cannot be written to. I’m used to
running SpinRite 6.0 from the past sans logs, so I did not fret too much about not having those for this exercise. Steve
Gibson is planning formal UEFI boot support for SpinRite 7 which should hopefully allow even booting from a mac, which
would solve for this in the future.
Is this the most performant way to run SpinRite? Maybe not. I’m not certain of the performance hit that might occur going through the x86 translation layer of QEMU. But regardless, if utter performance is not a concern, (meaning, you’re maybe willing ot wait a little longer for SpinRite to process a drive), it certainly is a great fallback approach to having to seek out x86 hardware in an increasingly ARM-based world.
Happy spinning, and Happy Holidays! 💿