Time Machine backup
can I keep a backup of an old Mac on the same external drive I'm using for Time Machine on my new computer?
Mac mini, OS X 10.11
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Hi Ltannas,
You have to partition the external drive; but yes you could. In such a case, I would suggest (assuming you have a new, fresh external drive to play with) following the below instructions:
https://support.apple.com/en-ca/guide/disk-utility/dskutl14027/mac
What I mean by that is, if the drive has enough space, and your old Mac backup is "sealed" (meaning you will not be modifying it and/or further updating it), I would suggest the following setup:
- Setup 3 partitions: One big enough to provide Time Machine backups that are 1.5-2 times your current internal Mac mini's used space (not the total space of the drive; but the actually used amount); Second for the a clone (backup of your current Mac mini setup, that is the same size as your Mac mini's used size plus ~100GB (for growth of use, etc.); and the third partition, to be the location for your old Mac's sealed backup.
- I do though caution that doing so (the partitioning) brings issues with it, that if you have both the Time Machine backup partition and a bootable clone of your current Mac mini on the same physical drive, if one partition acts up, you will very likely loose all partitions and the data on them respectively. That said, I have used a similar setup in the past without issue and would do so in the future, where the requirement needed (in my case).
I would though ask, as a question to yourself, if you have a separate backup application (like CarbonCopy Cloner or SuperDuper; I have not affiliation with either, except that I have used both with great success over the years and have owned/do each) to use, to create complete and bootable clones of your Mac mini's setup? If you don't, I strongly suggest looking at the idea as I find it easier to recover from a failed internal drive if I have a known-good, viable current setup external boot drive that I have cloned. Time Machine, I use for backing up certain folders really only on an immediate recovery basis and not as a bootable cloning mechanism. But each person needs to make a decision for themselves, and I am only offering my advice/suggestion from ~35 years of Mac usage here.
That said, please post back if you've questions and the community will try to help.
Cheers,
Anthony