Periodic Snapshot Tasks - retentio,

[fab67]

I changed a "Periodic Snapshot Tasks" frequency and now all old snapshots go from " Will be automatically destroyed ... " in "Will not be destroyed automatically"
Is this expected or a bug ?

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[fab67]

And with the screenshot.
Inital "Periodic Snapshot Tasks"

And after modification of the task frequency

 

[winnielinnie]

I changed a "Periodic Snapshot Tasks" frequency

What is the change you made in frequency?

If the snapshot name no longer coincides on the same interval as any existing task, then there's nothing that will mark it for destruction.

 

[fab67]

I only change the Schedule

I the example in #2, As you can see I only change the Schedule from 12:21 PM to 12:24 PM to test.
So It means you can't modify the task in any way ( time or day ) or deleting it without affecting the old snapshots retention behaviour ?

 

[winnielinnie]

And what was the Periodic Snapshot schedule before?

 

[fab67]

Oh I see, in the snapshot name there is hh:mm so if you change hours or minutes after that in the schedule, the naming pattern is changing and the old snapshots whith old naming pattern can no longer be attached to this task.
Correct ?
Conclusion, you have to choose the schedule ( hours and minutes ) carrefully in the first place.

 

[winnielinnie]

Bingo.

It's not intuitive, is it? I agree. I don't like the way TrueNAS uses Zettarepl to handle snapshots and pruning. There is no "database" or "table" that keeps track of snapshots, independent of their names. Zettarepl parses the names themselves. So if the snapshot's parseable name does not align with an existing task, there is nothing to prune it.

Likewise, the opposite is true. You can accidentally have old, archival snapshots destroyed without even knowing it, because of the same quirk about how Zettarepl works!

See here for more information:

Staged snapshot schedule

Hi! How would I best go about creating a schedule that creates snapshots of a dataset like this: 48 hourly 31 daily 48 monthly 12 yearly I think that I should create a separate schedule for each "frequency", but is there a better way?

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