Does macOS autosave snapshots apart from Time Machine?

[johnprogrammer]

Hello everyone.

I bought my first Mac, a Mac Mini M4, a couple of weeks ago.

I have setup Time Machine to do hourly backups, on an external SSD.

The question I have is, does macOS do backups (snapshots) on its own, apart from Time Machine?

 

[Bigwaff]

The question I have is, does macOS do backups (snapshots) on its own, apart from Time Machine?

Not sure what "on its own" means in this context but the APFS snapshot feature is used by other backup software (e.g. Carbon Copy Cloner, Arq, etc). Does this get to the crux of your question?

 

[benwiggy]

Yes, it can save APFS snapshots: but I wouldn't either rely on it as a backup; nor would I try to prevent it from doing so.

 

[johnprogrammer]

I use an external SSD enclosure that makes use of a Samsung SATA SSD 2TB.

I have configured Time Machine to use that for backups.

However, Disk Utility, shows a Data partition with Time Machine Backups, while I have configured Time Machine to use the external SSD, that shows empty.

See the photos attached.

 

[benwiggy]

I don't think that's anything to worry about.

 

[Bigwaff]

However, Disk Utility, shows a Data partition with Time Machine Backups, while I have configured Time Machine to use the external SSD, that shows empty.

Those snapshots are the temp hourly snapshot backups of your internal storage data volume which become backups on your TM disk. Your TM disk has no snapshots because TM is not backing up the TM disk, it's backing up your internal storage data volume. Eventually macOS/TM will delete the temp hourly snapshots.

 

[Brian33]

The snapshots on your data volume are a normal part of Time Machine operation. They will be automatically removed by TM, typically after 24 hours. If needed, you can remove them manually using disk utility. Just don’t remove the most recent one if there is a Time Machine back up in progress! I’m really not sure what value there is in retaining the snapshots, but I would leave them alone unless you have a specific need.

There are no snapshots showing on your backup volume because it is still in the process of loading them. You can see the spinner and the loading message at the bottom of your screenshot. Displaying snapshots on a hard disk drive volume can take a couple of minutes. If I remember correctly, your backups will appear as snapshots on that volume.