Smart Backup Retention

I have installed Duplicati and have been running it on multiple machines successfully for a few months now. Restores are working great as well.

I tried to look for this in previous questions, but it was hard to understand how the Smart Backup Retention works. I mean, I understand that it will keep a backup ffor the last 7 days, and 1 backup for the last 4 weeks and a backup for the 12. But here is my question regarding the monthly backups that are kept.

  1. If I create a file on 7/10/2019 and then that file is then deleted on 7/20/2019.
  2. Monthly backup is kept for 7/5/2019, 8/5/2019, etc.
  3. The file that was deleted on 7/20, will that be in my monthly backup that is kept for 8/5?

Please let me know if this sounds confusing.

Also, one more thing, how do I update the smart retention policy to keep backups for up to 7 years. I believe the smart retention policy only keeps backup for up to 1 year, is that correct?


No, a file deleted on 7/20 would not be present in the 8/5 backup that is retained. Each backup is a snapshot at that point in time. Deleted files are not carried forward.

If at some point your retention only keeps monthly backups, then a file that existed for less than a month may be unrestorable unless you got lucky with the timing of which monthly snapshot was retained.

I don’t know the answer to your other question about the smart retention but I know with custom retention you have full control over the timings.

To add to the great advice

Correct, however you can start with its value below and very easily base a custom retention on that.

For 7 years change 12M above to 7Y (change anything else you like) then call it your custom retention.

Note that retention is not calendar-based. It can only thin out the backups it has to the chosen density.