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BeatCrazy

macrumors 603
Original poster
Jul 20, 2011
5,120
4,480
Should be an easy question, but this has had me perplexed!

I have a Late 2013 Mac Pro, with 256GB SSD. I also have a 2TB HDD connected via USB for my media, etc. I have my Time Machine as a directly-attached 3TB HDD that is also a TM back up for my wife's Macbook Air.

My question: if I were to ever experience a failure with either my internal 256GB drive, or my external 2TB HDD, how would I restore with the same apps/media on the original drive(s)? How would the Time Machine restore know to put my OS & apps back on the 256GB, and put my media folders on an external drive? Seems like it would want to cram it all back on the 256GB drive, but of course it won't fit.
 

ItWasNotMe

macrumors 6502
Dec 1, 2012
454
318
Should be an easy question, but this has had me perplexed!

I have a Late 2013 Mac Pro, with 256GB SSD. I also have a 2TB HDD connected via USB for my media, etc. I have my Time Machine as a directly-attached 3TB HDD that is also a TM back up for my wife's Macbook Air.

My question: if I were to ever experience a failure with either my internal 256GB drive, or my external 2TB HDD, how would I restore with the same apps/media on the original drive(s)? How would the Time Machine restore know to put my OS & apps back on the 256GB, and put my media folders on an external drive? Seems like it would want to cram it all back on the 256GB drive, but of course it won't fit.

Time Machine keeps the volume structure within each backup so it looks like

\Backups.backupdb\<Machine>\<Date of Backup>\<Volume>\<Folder>...

so restore has the full path of the source

where:
<Machine> is e.g. the name given to your Pro or your wifes Air
<Volume> is the name of the drive thats being backed up, there is one of these for each drive on each machine
<Folder>... is the structure on that volume that is in scope for Time Machine
 

simonsi

Contributor
Jan 3, 2014
4,851
735
Auckland
Should be an easy question, but this has had me perplexed

When your TM drive is connected, browse it with Finder, you will see the machine and drive structure set out for you as above.

If/when you come to restore TM will ask you which drive to restore to and put back the files that were on it.

PS - your backups are just "interesting", you need to be confident that you can actually restore when you need to so if you have a spare drive (or can temporarily borrow one), do a practice restore to that drive. Then check it has the files on it it should have - only then will you know your backup is being done correctly end-to-end.
 

BeatCrazy

macrumors 603
Original poster
Jul 20, 2011
5,120
4,480
Time Machine keeps the volume structure within each backup so it looks like

\Backups.backupdb\<Machine>\<Date of Backup>\<Volume>\<Folder>...

so restore has the full path of the source

where:
<Machine> is e.g. the name given to your Pro or your wifes Air
<Volume> is the name of the drive thats being backed up, there is one of these for each drive on each machine
<Folder>... is the structure on that volume that is in scope for Time Machine

I see, that makes sense. Thanks.

When your TM dcrive is connected, browse it with Finder, you will see the machine and drive structure set out for you as above.

If/when you come to restore TM will ask you which drive to restore to and put back the files that were on it.

PS - your backups are just "interesting", you need to be confident that you can actually restore when you need to so if you have a spare drive (or can temporarily borrow one), do a practice restore to that drive. Then check it has the files on it it should have - only then will you know your backup is being done correctly end-to-end.

Thank you. Good idea about doing a practice run. I do have a couple of 400GB spinners that I could use to test with. Although I'm not 100% sure how to practice-restore my boot drive if the original one is still healthy.
 

simonsi

Contributor
Jan 3, 2014
4,851
735
Auckland
I'm not 100% sure how to practice-restore my boot drive if the original one is still healthy.

Create another boot drive ;)

Connect both your TM drive and a spare drive
Option key boot and boot off the TM drive
TM will ask which drive to restore to and which backup to use, restore your boot drive backup to the spare drive.

To test, shutdown, disconnect the TM drive, Option-boot and boot from the spare drive, it should come up just as you main drive, same login, same apps, same user settings.

Restart and it will boot from the internal drive (no need to Option-boot).

Test completed and you will be one of the "Well Prepared" :D
 

BeatCrazy

macrumors 603
Original poster
Jul 20, 2011
5,120
4,480
Create another boot drive ;)

Connect both your TM drive and a spare drive
Option key boot and boot off the TM drive
TM will ask which drive to restore to and which backup to use, restore your boot drive backup to the spare drive.

To test, shutdown, disconnect the TM drive, Option-boot and boot from the spare drive, it should come up just as you main drive, same login, same apps, same user settings.

Restart and it will boot from the internal drive (no need to Option-boot).

Test completed and you will be one of the "Well Prepared" :D
Thanks for the detailed explanation. I'll be trying this in a few days!
 
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