Re: [Duplicity-talk] Newbie/General Questions

[SanskritFritz]

On Sun, Dec 4, 2011 at 2:01 PM, email builder <address@hidden> wrote:
> 1) The Ubuntu One backend - manpage says you have to be running
> under X where you will be prompted for your credentials.
> I'm trying to set up duplicity on a server to back up some critical data
> from a cron, so can I take this to mean the Ubuntu One backend is
> out of the question to me?

Yes, because it is ubuntu one that is asking for the credentials.

> 2) When run with simple default, umm, to what GPG recipient does
> the data get encrypted??  I am confused by this missing info.

I dont understand this question.

> a) I saw something about "symmetric encryption" and just learned for
> the first time that GPG can do symmetric encryption.  In this case,
> are you prompted for the passphrase interactively?  Can that be
> automated (so it can be run from cron)?

Yes, it is interactive, and well, with some (ugly) hacking it is
possible to run from cron, but this is what asymmetric encryption is
for.

> b) Is using --encrypt-key the way I can make duplicity use Asymmetric
> encryption?  In this case, does it use the public key from the current
> user's keyring?

I'll let others answer this, I use a wrapper for duplicity which hides
such details from me.

> 3) I'm a little confused by the concept of "sets" and the need to
> remove sets of a certain age, etc.  My goal is to find a way to back
> up some user data in its current state, no need to keep track of the
> historical state of that data.... well, as long as it takes extra storage,
> which I assume it does, yes?

There is no need to remove any sets. But after a while your chain of
sets will be pretty long, which makes it slow to restore any data.
Hence it is recommended to do full backups time to time, and delete
old sets after. Having said that, I never do that, I always keep all
my backups, and duplicity handles it just fine :)

> a) Is there a way to do what I thought traditional rsync does - just
> keep a mirror of my current data and no historical information?  What
> options do I need to do this?

That is what rsync is for, right? Duplicity cannot mirror AFAIK, it
packs your files into archive sets.

> b) How much extra storage is required to keep incremental historical
> backup data ("sets"?)?  I know this will probably be a question you
> can't answer exactly, but I'd just like to understand the basics, say
> for weekly backups of email data.

Minimal, just what is needed. Duplicity sends only those parts of
files that differ from the previous versions. Look for delta in the
docs. I have my home directory backed up, the first full backup took
90MB, and 14 incrementals take only 16MB in a time span of more than
two months.

> 4) Tips on good backup locations... anyone used duplicity with
> box.net or similar services?

Yes, I used webdav, works great. You may also try mydrive.ch, it
offers 2GB with unlimited traffic. I do regular backups on it via
webdav. There were some problems with webdav in the past, seems all
bugs affecting webdav are now ironed out. Keep in mind, webdav server
implementations dont follow the standards exactly, hence expect
hitches sometimes.

> Should I split this email into one for each question topic?
Yes, please. Oops, too late now :) Or is it?

Best regards.