Deja dup not backing up according to schedule

I have set deja dup to backup daily, but it seems to back up whenever it feels like it. Sometimes after 1, 2, or 3 days. I use my computer many hours per day, so it’s not that the computer is off. Wondering if I have missed a setting somewhere.

It should do incremental backups on schedule, with fresh back ups from time to time. If you open it does it not say “next back up is …”? Mine does here—weekly backup works just fine. If the computer is off/suspended, it seems to backup when the computer is next available.

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Hi Ankur.

Yes it should, but it doesn’t.

Yes, it says “Next backup tomorrow” and then it may or may not actually do the backup.

I can’t figure out this strange behavior. Is the problem maybe in one of these “check” settings in dconf? I don’t understand exactly how they work.


Can you try a “restore” just to see what dates it lists backups for? It’ll be good if we can have some more info on when it is actually backing up—maybe there’ll be a pattern there that will tell us something.

We shouldn’t need to tweak any of these—I certainly haven’t ever touched them.

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Here are some recent backup dates.

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So it does seem to do it quite regulary—even daily for a bit. Maybe it’s just dependent on when the system is on (not suspended/powered off)? The only complete test is to leave the system running for a couple of days to see if backups do happen daily.

There’s some info here:

The source for the scheduler is here if you want to take a look—the comments explain it a bit:

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It seems to me that Deja will check (as a guaranteed minimum) once a day. If the computer happens to be off or suspended (I always suspend when away), then the check will fail. It also seems to prefer nightime and my computer is always asleep at night. Deja claims it checks on login, but this does not seem to actually happen unless they mean a login after a logout rather than simply entering my password for screen lock after waking computer up. I only logout after major updates.

They talk about various other “triggers” but these seem to catch backup failure after 2-3 days (not efficient). I don’t know why they don’t use anacrontab which is very efficient (not cron which has similar problems). I was using rsync with anacrontab before but switched to deja cuz I liked the interface and versioning. However, this comes at a cost as it is not reliable to follow the users backup schedule. I will look into using duplicity directly, or maybe it’s better to use rdiff with anacrontab. What do you think?

There’s a “why not cron” section in the page here, and I expect the same reasons apply to anacrontab:

Sure, anacrontab would work well. I’m sure lots of folks have their own scripts that runs duplicity/rsync with anacrontab. I’ll see if there’s a way of telling deja-dup what time we want it to backup—that way we can ask it to backup during the day when we know our systems will be up.