Custom retention rules

I want to retain all file version for 2 months; after that for files up to 6 months old, twice daily; and after a year 1 a month! And perhaps after that I need less copies, say max 3. So would that be “2M:0s,6M:2D,1Y:1M, U:3”?

What happens between 6 and 12 months - I’m missing something. I tried a different retention set which gave warnings on backup, so have reverted to the standard 6 month rule temporarily. I looked at other threads and can’t work out what I am doing wrong.

Backing up to BackBlaze B2 if that makes any difference.

For the 2M time, optionally say U instead of 0s if it’s more meaningful. They should work the same – unlimited. IIRC this is one where the documentation hasn’t caught up in all places. I’ll mention a second suspect later on.

For the 6M time, I’m glad you said “up to 6 months”, and the start of that period is after the 2M time is finished.

For the 1Y time, you said “after a year”, then talked about “after that”. 1Y time (and any time) is an up-to age. The interval setting for this time (and for any time) begins after the prior time (6M in this case) has completed.

I don’t think you can make the value after the colon change from an interval into a count by leaving off its unit.

Capping the copy count is done by capping the time range, so instead of U you could try 4Y:1Y or something. Although it’s possible not all the documentation has caught up, backups now delete after retention times end.

I’ll try


[edit - ran with no warnings :ok_hand:]

I assume that means, in my example above,1 copy will be kept after 2 years

When I forget, I can always look back on your post :smiley:

No, deleted is deleted. You’re OK provided the file is still in source, because more recent backups will have it, however if the file is gone, and every backup that had it is gone, then you’ve missed last chance to recover it.

If you want backups kept for the long term, you can continue specifying larger and larger times and intervals.

Duplicati is very point-in-time-version oriented, and this shows up in the Restore window. You get THAT view.
Coming from CrashPlan you might be used to a view offering per-file dates, and even an option to show files deleted by then. You can also specify deleted file retention handling specially. Duplicati works differently now. Feature additions can be suggested, but tend to get prioritized behind other more important things going on.

IIRC CrashPlan’s risk is in reconfiguration, but it warns about file/folder removals from all your older versions. Duplicati reconfiguration only affects new backup versions. Old ones just age until (maybe) they get deleted. You have to work some, if for some reason you want to delete something from every version of your backup.

So I didn’t quite understand after all. But I have time to get this right.

Really appreciate your help.