Re: Questions about deja-dup

[Michael Terry <mike mterry name>]

On Mon, Feb 12, 2018, at 07:26, Anna Marei wrote:

Hej thanks for your time! Inline replies as well ;)

Michael Terry <mike mterry name> hat am 11. Februar 2018 um 19:15 geschrieben:

Hello! Inline replies below.

On Wed, Feb 7, 2018, at 06:43, Anna Marei wrote:

Hello, I've started to learn how to use secure backup techniques and have a few open questions about deja-dup that have not been covered by articles yet. I hope someone on this list can help me!

1. I read that deja-dup uses gpg2 to encrypt the backups. Where and how can I set my own keys for this? In Evoulution Mail it works quite simply. It searches for existing keys.

Deja Dup only uses gpg2 for symmetric encryption (i.e. using a passphrase, not a key). Duplicity (the underlying backup tool) can use key-based encryption, if you require that.

So i have to tweak dconf-editor settings here as well?

How secure is symmetric encryption?

No no you can’t enable key support via dconf-editor. I just mentioned duplicity because maybe you could use it directly if you needed key encryption.

Symmetric encryption is as secure as the password you use.

But deja-dup doesn't implement that side of things (we aim at more casual users who probably don't have a gpg key).

What about make it an possible alternative as well?

My general feeling is that if you know enough to ask for a feature, you are no longer Deja Dup’s target audience. 🙂 But that’s partly a way to dodge new work, because every new new feature costs time.

2. I saw that this feature request would still be very useful. https://bugs.launchpad.net/deja-dup/+bug/479191
But the request  was from 2009. Now it's 2018. Any progress on that?

No progress really. It hasn't been a focus for me.

Ok, what is on your focus for deja-dup? And what could bring this issue to the foreground?

My focus these these days is critical bug maintenance and better integration with GNOME. But I haven’t spent a lot of time on Deja Dup lately.

To address the better scheduling issue, I’d be interested to see some design thought going into it. My gut take is that it is hard to do in a way that is also elegant and understandable. Again, the target audience for Deja Dup is those who wouldn’t normally make a backup, so the less confusion/barriers in the way, the better. Advanced scheduling seems like a luxury in that context.

3. Is it bad if I change the interval of backups from daily to weekly in an ongoing backup cycle, as described in https://wiki.gnome.org/Apps/DejaDup/HowItWorks "Deleting old backups"?

No, that's fine.

Cool, thanks! This works for 5. (see below) as well?

4. What happens if only one of these backup files doesn't work anymore? I read i need all of them From full backup A to incremental backup A4.

If an incremental backup is corrupted somehow, you can restore up to the incremental before the corruption. Or the next full backup (which is one reason we occasionally make fresh full backups). But all incrementals after the corrupted volume will not be usable.

Deja-dup checks this automatically if i hit restore button, right?

Yeah it will complain loudly if it can’t understand an incremental backup file. It also periodically (every two months) checks if it can restore a canary file to confirm that nothing is hideously broken.

5. On the help section "Deleting old backups" i read that "Déjà Dup lets you specify that you want backups to be kept for a period of time (say, a month)" -> But there as the options seems to be hard coded here there is just 6month/1year/forver

Will you make it possible to select all the dates and periods manually in the nearby future? That's related to 2. as well.

The UI is restrictive in what options we allow. But you can set whatever period of time you want using dconf-editor (navigate to /org/gnome/deja-dup/delete-after).

Cool, thanks. It seems to work for me now!

Hope that helps!

-mt