Apple Intelligence is now available on iPhone, iPad, and Mac!

📢 Newsroom Update

Apple unveils the new iMac with M4, supercharged by Apple Intelligence and available in fresh colors. Learn more >

📢 Newsroom Update

Apple introduces M4 Pro and M4 Max. Learn more >

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Disk for Time Machine

I considered to start to use Time Machine for a total backup of my two iMac's. Is it possible to use one external HD on one of the computers and share it to the other one? And how shall I think about size? If I today have one machine with 1,7 TB data on a 2 TB HD and the other one has 0,45 TB date on a 1 TB disk.

iMac (2017 – 2020)

Posted on Sep 18, 2023 11:41 AM

Reply
Question marked as Top-ranking reply

Posted on Sep 18, 2023 11:51 AM

You can use a single external drive for two different Time Machine backups, but only if you've partitioned the external drive (and given each partition a different name so you know which is which). When you run Time Machine you'll need to tell it which partition to use.


Best practice is to use an external drive that's twice the size of the Mac you're trying to back up. So I'm seeing a 4TB drive for your 2TB Mac, and a 2TB drive for your 1TB Mac. So a 6GB drive would be what you want.


(Might be less expensive to get two external drives...a 4TB and a 2TB).

Similar questions

5 replies
Question marked as Top-ranking reply

Sep 18, 2023 11:51 AM in response to bodal

You can use a single external drive for two different Time Machine backups, but only if you've partitioned the external drive (and given each partition a different name so you know which is which). When you run Time Machine you'll need to tell it which partition to use.


Best practice is to use an external drive that's twice the size of the Mac you're trying to back up. So I'm seeing a 4TB drive for your 2TB Mac, and a 2TB drive for your 1TB Mac. So a 6GB drive would be what you want.


(Might be less expensive to get two external drives...a 4TB and a 2TB).

Disk for Time Machine

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.