I have an external HD formatted using exfat. I have my backups from my windows computer on it. Is it possible to partion this drive using my Imac, keeping all the current data and use it with time machine? How much space should i use for back ups? I have a 1tb internal and a 2tb external.
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Back up on External HD
- Thread starter Cheddardip
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Your backup drive/partition should be at least the size of the internal drive you're backing up, and must be formatted as HFS+ a.k.a. Mac OS Extended (Journaled)
Sure, just add a Mac OS Extended partition for Time Machine to use. The size of the internal drive is not really necessarily directly related to the size of your backup drive. What is relevant is how much data you have or expect to have.
Use me for example, I am currently using about 60GB drive space total. About 30GB of that is user files like documents, music, and photos. So even if I eventually double the amount of user files I have (not likely soon), I would be using 60 + 30 = 90GB of space. Even if I doubled that for a Time Machine backup to allow some space for "versions" of files, my Time Machine drive would then need only to be 180GB.
So just look at how much data you think will have then add a 1.5X or 2X buffer for versions.
This will show you how to add a partition.