Catalina Migration Assistant consistently destroys TimeMachine backups - BEWARE - HELP NEEDED

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Catalina Migration Assistant consistently destroys TimeMachine backups - BEWARE - HELP NEEDED

I have 3 TimeMachine NAS backups of my MacBook Pro, each one in a different location, two on a Synology NAS and one on a Time Capsule. So when I got my new MBPRO 16“ I thopught it would be safe to use Target Disk Mode and Migration Assistant to transfer my data. The process started normally and got stuck at 107,000 documents or so. Then, the target computer crashed and restarted. The source computer was unable to boot after that and I could not repair it using recovery mode tools (I tried everything).

Next I tried to restore from my latest NAS Time Machine Backup. Migration Assistant would not recognize the (encrypted) backup so I had to manually mount and open the backup file. Migration assistant went to work and after one night crashed (did not complete), with the same result: the new MBPRO would not boot and the backup data on the NAS was destroyed - deleted!

Thinking there might be an issue with the Synology NAS and TimeMachine, I went to my TimeCapsule backup. Again the Migration Assistant would not recognize the backup at first, mounted it manually, then started. This morning I found the MBPRO with a boot screen, entered my credentials and it ... crashed. Recovery mode told me nothing had been copied and the OS is unable to boot, I had to reinstall.

Then I tried to access the TimeCapsule backup manually. It was destroyed, only 25MB or so left of a 2TB backup file.

I have one NAS backup left which I am copying to an external HD ...

Can someone help me? Apple support just wants me to try the things that already failed 3 times. For example, how can I restore from an encrypted backup file that I copied from a NAS to an external HD?

For everybody else ... be forewarned. TimeMachine / Migration assistant is causing irreparable data losss!

MacBook Pro with Touch Bar

Posted on Dec 3, 2019 3:38 AM

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Answer 1

Top-ranking reply

stwphanfromboston Author

Level 1

8 points

Dec 6, 2019 6:23 AM in response to LaPastenague

Here is what worked for me eventually:

From the last remaining NAS backup on a Synology NAS, I made a copy to an external HFS+ formatted disk. The TimeMachine file is 4TB. Finder was unable to copy it and RSYNC was too slow (I would have to wait several days). So I plugged in the HFS+ formatted 5TB disk directly into the NAS and copied the data that way. It took about 30 hours.

I was able to access this backup AFTER manually opening it and providing the password; TimeMachine still does not recognise the encrypted backup file. I was then able to restore files selectively.

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Answer 2

Dec 3, 2019 4:52 PM in response to stwphanfromboston

I did a long thread about it several OS versions back so I cannot guarantee what will happen with Catalina. I am pretty sure it worked up to Mojave.

https://discussions.apple.com/thread/7236090?answerId=28992389022#28992389022

The encrypted backup is no problem as you are using Time Machine.. but from Recovery not main OS.

You will produce a non-encrypted full restore boot drive doing this..

But please tell me if you run into issues. I don't even have a Mac that I can upgrade to Catalina now.. nor do I care to.

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Answer 3

Dec 3, 2019 12:17 PM in response to stwphanfromboston

What Mac OS version is used with your backup?

If it is Mojave or something earlier then I would change the OS on your computer back to mojave. You should be able to run setup assistant from recovery and reload the OS as it existed. I would do this to the Mac Internal disk but if you want it is possible to recover the whole OS to external drive. You can do it from network or from the archive of the backup.

Sorry I just cannot give much more.. I am getting too old to go through this pain every 12 months.

We are seeing lots of issues with Catalina none as bad as your experience.

Apple were not helpful at all and providing useless suggestions as you got.

My very strong recommendation is use Carbon Copy Cloner or similar 3rd party and forget Time Machine. It is now so unreliable as to be useless. But you need to get one machine up and running to make the clone.

Next time.. remember this pain and always have available a working bootable clone so when you get this sort of disaster you just boot from the clone to recover.. easy peasy.

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Answer 4

Dec 3, 2019 2:06 PM in response to LaPastenague

Unfortunately all backups had been “converted“ by Catalina already. So I can‘t go back to Mojave. I‘m looking for a reliable way to mount an encrypted backup (which I copied from the NAS) read-only, so that I can copy individual files. Any ideas?

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Answer 5

Dec 3, 2019 2:40 PM in response to stwphanfromboston

Extracting files is going to be very difficult.

Did you try using recovery on a Mac and run Setup Assistant?

That is the only way to go back to earlier backups in Time Machine.

If you can mount the backup that way then recreate your original boot drive to a USB disk plugged into the computer.

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Answer 6

Dec 6, 2019 12:16 PM in response to stwphanfromboston

That must be a huge relief. Well done.

Going forward.. DO NOT TRUST TIME MACHINE.

There was a good article recently in OWC blog.. which is pretty much identical to what I was suggesting.

But worth a read to anyone else following through this thread to find answers.

https://blog.macsales.com/56409-how-to-restore-data-from-time-machine-backups/?

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Answer 7

Dec 3, 2019 3:03 PM in response to LaPastenague

Can you explain that to me? Not sure I fully understand.

Run recovery
Reinstall OS
During OS setup access drive with encrypted backup? Will it recognise it, or do I have to decrypt in manually?

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Catalina Migration Assistant consistently destroys TimeMachine backups - BEWARE - HELP NEEDED

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