Problems after failed installation of Big Sur with no backup

[davebquinn]

Hi

My Dad (honest!) tried to update his OS to Big Sur on his 2015 iMac yesterday. It failed, and he hadn't backed up for a year Failing in my duties, I know but unable to see him for many months because of Covid

I have tried to install the new OS in recovery mode but it keeps stalling. I have run Disc Disk Utility in recovery mode, running first aid on Apple SSD AP0032H media tells me that its corrupt, needs to be repaired which I have tried but it doesn't work. "Incomplete or inconsistent CoreStorage Physical volume set Storage system exit code is 1. Problems were found with the partition map which might prevent booting. Storage system verify or repair failed : (-69716)

the other two parts (?) of the disk - Mac SSD and Mac SSD Data are fine.

I installed Big Sur onto a SSD external hard drive and booted the iMac using that. I can see the old Applications, Library, System and Users folders in locations/Mac SSD in the side bar, and I have copied everything to another external hard drive, all his docs and work have copied over and can be opened fine. The Mac SSD - Data disc that shows up in Disk Utility doesn't show up in locations in the side bar.

My question is is there any way of avoiding a completely fresh install and then copying the documents over. The last backup we have is from August last year so, its not the end of the world but My Dad's 85, and struggling with his sight and any new learning or settings are a bit tricky for him. If we could avoid starting from scratch it would be good

Obviously, I should have checked he'd been backing up, I'll be making sure his iCloud back up is working now and set to back up regularly.

Many thanks in advance for any help

 

[Fishrrman]

All my advice assumes that you are able to:
1. Boot from an external drive
and
2. You're able to "see" his internal "SSD Data" drive on the desktop.

The important thing is to GET ALL OF HIS DATA OFF THE INTERNAL DRIVE and onto an external drive first. Sounds like you have done this. However, be aware that once you get a system installed, you may have to "restore him" "by hand".

What I would do:
1. Get CarbonCopyCloner (free to download and use for 30 days)
2. Use CCC to create a cloned backup to an external drive
3. (still booted from external SSD as you've been doing) -- Open disk utility
4. Go to the view menu and choose "show all devices" (VERY important step)
5. Now, ERASE the ENTIRE internal SSD to APFS with GUID partition format.
6. When done, quit disk utility and open the OS installer if you have it available.
7. Install a fresh copy of the OS to the internal SSD. The Mac will reboot several times, and the display may "go dark" for several minutes one or more times. Be patient.
8. When done, you should be booted from the internal SSD and see the opening display "choose your language"
9. Now start "clicking through" the setup.
10. At the appropriate moment, setup assistant will ask if you wish to migrate from another drive. YES. Pick the external backup and give setup assistant some time to "digest everything". BE PATIENT.
11. You should see a list of things available to migrate. I suggest you accept all of it, and just click the button to continue/proceed with the migration.
12. Again, be patient.
13. When done, you should see your dad's login screen.

IF you DO NOT have an OS installer on the external drive you're booted from...
Then power down all the way off.
Then reboot to INTERNET RECOVERY:
Command-OPTION-R
at boot.

You'll need your wifi password and the internet utilities may take a while to load.
Try the OS installer that is offered to you there...

 

[posguy99]

My question is is there any way of avoiding a completely fresh install and then copying the documents over. The last backup we have is from August last year so, its not the end of the world but My Dad's 85, and struggling with his sight and any new learning or settings are a bit tricky for him. If we could avoid starting from scratch it would be good

Why would you waste your time dancing this? You stated you recovered the important data, wipe the drive and reinstall.

Then implement something like Backblaze to keep the data backed up.

 

[davebquinn]

All my advice assumes that you are able to:
1. Boot from an external drive
and
2. You're able to "see" his internal "SSD Data" drive on the desktop.

The important thing is to GET ALL OF HIS DATA OFF THE INTERNAL DRIVE and onto an external drive first. Sounds like you have done this. However, be aware that once you get a system installed, you may have to "restore him" "by hand".

What I would do:
1. Get CarbonCopyCloner (free to download and use for 30 days)
2. Use CCC to create a cloned backup to an external drive
3. (still booted from external SSD as you've been doing) -- Open disk utility
4. Go to the view menu and choose "show all devices" (VERY important step)
5. Now, ERASE the ENTIRE internal SSD to APFS with GUID partition format.
6. When done, quit disk utility and open the OS installer if you have it available.
7. Install a fresh copy of the OS to the internal SSD. The Mac will reboot several times, and the display may "go dark" for several minutes one or more times. Be patient.
8. When done, you should be booted from the internal SSD and see the opening display "choose your language"
9. Now start "clicking through" the setup.
10. At the appropriate moment, setup assistant will ask if you wish to migrate from another drive. YES. Pick the external backup and give setup assistant some time to "digest everything". BE PATIENT.
11. You should see a list of things available to migrate. I suggest you accept all of it, and just click the button to continue/proceed with the migration.
12. Again, be patient.
13. When done, you should see your dad's login screen.

IF you DO NOT have an OS installer on the external drive you're booted from...
Then power down all the way off.
Then reboot to INTERNET RECOVERY:
Command-OPTION-R
at boot.

You'll need your wifi password and the internet utilities may take a while to load.
Try the OS installer that is offered to you there...

Thanks very much for the detailed reply, it was really helpful. After a lot of messing around I got there

It turns out the iMac had two internal SSD drives, the smaller drive, OS drive, wasn't big enough for Big Sur and so the installation kept stalling.

I cloned the hard drive as you suggested, but when it just wouldn't migrate the data in the setup assistant when I was installing Big Sur I had to do a completely fresh instalation and copy the files from the cloned disc and from the older backup.

All good now, and removing a lot of stuff he never used has helped him a lot, his sight is really deteriorating so having less of everything works.

Thanks again.

 

[davebquinn]

Why would you waste your time dancing this? You stated you recovered the important data, wipe the drive and reinstall.

Then implement something like Backblaze to keep the data backed up.

Thanks for the backup suggestion, a cloud backup is a good idea for him ??