Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Howard2k

macrumors 603
Original poster
Mar 10, 2016
5,228
5,056
I backup to a NAS and to an external USB drive. I replaced my NAS and so am also re-working my backup structure.

I'd like to keep another backup, but I don't really want to have Time Machine manage this third drive for me. Largely because of the local snapshot issue.

My plan was to just copy the Time Machine backup from the USB drive to another MacOS formatted drive, which I can then store off site.

I guess really I should just try this out and see if it works, but I'm hoping someone has done this before and can provide some feedback as to how well this worked?


Time Machine -> NAS as normal.
Time Machine -> external USB as normal.

And then my third drive would just be a data copy of the above external USB drive to another USB drive which I would then store off site.

Any significant alarm bells you guys can think of?
 

CoastalOR

macrumors 68040
Jan 19, 2015
3,022
1,147
Oregon, USA
I backup to a NAS and to an external USB drive. I replaced my NAS and so am also re-working my backup structure.

I'd like to keep another backup, but I don't really want to have Time Machine manage this third drive for me. Largely because of the local snapshot issue.

My plan was to just copy the Time Machine backup from the USB drive to another MacOS formatted drive, which I can then store off site.

I guess really I should just try this out and see if it works, but I'm hoping someone has done this before and can provide some feedback as to how well this worked?


Time Machine -> NAS as normal.
Time Machine -> external USB as normal.

And then my third drive would just be a data copy of the above external USB drive to another USB drive which I would then store off site.

Any significant alarm bells you guys can think of?
There is not an easy way to "data copy" one Time Machine Drive to another.
Here is Apple recommendation on how to transfer Time Machine backups:
https://support.apple.com/en-us/HT202380

The problem is the slowness of the transfer (I think it was about 24 hours to transfer 1 TB) and there is no way to update because of all of the hard links.

I thought I would try Carbon Copy Cloner (CCC) since is also will do incremental updates, but it would not clone the Time Machine disk. I changed my strategy to use 2 cloned CCC disks and rotate them on and off site. Another option is to look at cloud storage for your off site backups.
 
Last edited:

getrealbro

macrumors 6502a
Sep 25, 2015
604
262
As CoastalOR says, a file level copy of a Time Machine backup is almost always painful -- they can take days. A block level copy is faster BUT much less safe, because it doesn’t check the destination for bad blocks, etc.

I’d look at what you really need the 3rd backup for. Often the 3rd backup may only need to cover the loss of mission critical or irreplaceable data e.g. accounting/billing info., a photographers photos, etc.. In that case Carbon Copy Cloner can maintain the 3rd backup pretty easily.

GetRealBro
 

Howard2k

macrumors 603
Original poster
Mar 10, 2016
5,228
5,056
Thanks for the feedback. I’ll try the file level copy and see how painful that is. And if it’s too painful i’ll perhaps just do a manual copy of key files.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.