Upgraded to Big Sur and had a problem. Restored back to Catalina. After that, Finder shows 2 Machintosh disks and another called Update. Can I remove those 2? System is running OK. Not sure where those 2 references came from. I renamed one to Data1
iMac Line (2012 and Later)
Yes, it is safe to delete this "Update" volume as well.
As you wrote at the outset, these resulted from the aborted update. Nothing to worry about.
See Screen Shot from Disk Utility
Thanks - any idea where these 2 files/disks came from?
Open Disk Utility.
You should have a volume called Macintosh HD using about 11GB, and a Macintosh HD - Data; you need to make sure to not delete the wrong things.
You must have one volume that says "Mount Point: /" that is your system, and is mounted read-only; and a volume that says:
This is your active Data volume, and of course you can't and don't want to lose it.
It may be clearer if you open Disk Utility and post some screenshots.
These MUST stay:
You can safely delete this "... Data 1" volume.
Control-click and choose Delete APFS Volume.
You can probably also do the same with the "Update" volume, but to be safe please post a similar screenshot first just to confirm.
Upgraded to Big Sur and had a problem.
