How to use Time Machine with multiple internal disks to a single external hard drive

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TrailGirls Author

Level 1

4 points

How to use Time Machine with multiple internal disks to a single external hard drive

I have a MacPro desktop computer (mid 2012) with 3 drives:

A. 500 GB Flash Storage - used for programs

B. 2 TB SATA Disk - used for Data

C. 2 TB SATA Disk - used for back up of Data disk

When I set up the computer initially, I chose to use 'C' as my back up disk for Time Machine, and only set it up to back up 'B'.

I am going to purchase a 5 TB La Cie external HD and want to set it up to back up all 3 above disks, and subsequently use disk 'C' above for regular use.

My questions:

How do I remove the backup data from 'C' above, prior to backing up to my new external HD?
What do I need to change in Time Machine in order for it to back up all 3 drives?

Thanks in advance.

Mac Pro

Posted on Apr 15, 2020 4:40 PM

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Answer 1

Top-ranking reply

BDAqua

Level 10

245,177 points

Apr 15, 2020 5:31 PM in response to TrailGirls

In SysPrefs>Time Machine, click Select Disk... Highlight "C" & click Remove.

From Available Disks choose the new drive you've Formatted HFS+, MacOS ExtendedJournaled, GUID Partition scheme.

In SysPrefs>Time Machine, click Options, highlight & Remove excluded Drives using the tiny minus Icon.

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Answer 2

Apr 15, 2020 6:43 PM in response to TrailGirls

Time machine will try to back up every MacOS drive you have, unless you follow the details of what BDAqua said -- to exclude that one drive.

Remember that Windows-native drives (if you ever have any) are NOT MacOS drives, and will NOT be backed up by Time Machine. You need a Windows-native backup system for those.

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