ZFS Snapshots and Time Machine SMB Shares--Expected Behavior?

TrueNAS General
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I know there’s been a ton of work from the dev team in the last couple of years to make Time Machine backups to TrueNAS SMB shares more reliable–and in particular, more compatible with ZFS snapshots.

So, for instance, by default an SMB share configured as having Purpose: Time Machine Backupwill create a ZFS snapshot after every successful backup, so the Time Machine sparsebundle is in a consistent state when the snapshot fires.

I had a couple of questions about how that works in 2026/TrueNAS CE 25 (and 26).

  1. Since we want snapshots consistent with Time Machine’s backups, I’m assuming best practice is to exempt the Time Machine directory from any other scheduled automatic backup?
  2. Do the Time Machine snapshots prune themselves? If not, I’m assuming the best way to handle them is to treat them as manual snapshots and automate deleting them … however manual snapshots are best automatically deleted? (I’ve not had to schedule automatic deletion of manual snapshots before).
  3. TrueNAS 27? Are there any significant changes coming to TrueNAS 27 that will impact Time Machine?