Is it possible to use an external HDD for time machine backups and regular files at the same time?

[Pangalactic]

If I have a 4TB external HDD, is it possible to somehow allocate 2TB for time machine backups, and 2TB for regular files like movies? Or do I need two different HDDs for this?

 

[Basic75]

Yes, it's possible. You can either make a single volume/partition and just use it for both purposes, or create two partitions of 2TB each if you want static limits.

 

[hg.wells]

Also remember though, it’s not creating separate drives - so if you’re backing up data stored on the drive to a Time Machine partition on the same drive and the drive fails you’ve lost everything.

 

[Fishrrman]

You would have to partition the drive.

BUT... I would not use a tm backup drive for anything else. Things will just go easier that way.

 

[arw]

I encountered no problems whatsoever with a configuration like you suggest.
I split my external backup drive into 2 partitions.
- Partition 1 is used by Time Machine to create backups of the Macs local SSD.
- Partition 2 is a backup of a mounted network share that gets updated each day with a rsync command.
This way I have one physical drive with my Macs local (system) files and all my data from my NAS/server.

As mentioned, if you can afford it do yourself a favor and keep your precious backup drive separated from other (junk) data. It just simplifies things in the long run.

 

[NoBoMac]

Depends on which OS you are on.

Recent versions of Time Machine will format the drive as APFS, so will need to use command line to limit each partition to 2TB. And that, imo, is a bit overkill: let APFS do its thing and have the partitions share the drive space. A bit wasteful (silly?) to potentially over allocate space to one partition or another.

 

[Macky-Mac]

for years I've been using external drives for both time machine backups and other data files.....and I've never partitioned the drives......I've been using older MacOS versions tho, so the current versions may require a different arrangement

 

[MacCheetah3]

If I have a 4TB external HDD, is it possible to somehow allocate 2TB for time machine backups, and 2TB for regular files like movies?

Yes.

Partition a physical disk in Disk Utility on Mac

In Disk Utility on your Mac, add, delete, erase, or enlarge a partition on a storage device.

support.apple.com

I’ve had a similar setup for years (the “Storage” partition is primarily ripped movies):






*** The media type is not “solid state” rather a 2.5” HDD. I’m not sure why Disk Utility is identifying it incorrectly.