Re: [gentoo-user] {OT} rdiff-backup: push or pull?

[Grant <emailgrant@gmail.com>]

>> I'm setting up an automated rdiff-backup system and I'm stuck between
>> pushing the backups to the backup server, and pulling the backups to
>> the backup server.  If I push, I have to allow read/write access of my
>> backups via SSH keys.  If I pull, I have to enable root logins on each
>> system to be backed-up, allow root read access of each system via SSH
>> keys, and I have to deal with openvpn or ssh -R so my laptop can back
>> up from behind foreign routers.  The conventional wisdom online seems
>> to indicate pulling is better, but pushing seems like it might be
>> better to me.  Do you push or pull?
>
> I would push, to be honest.

Me too.  The rdiff-backup "UnattendedRdiff" wiki page only has
instructions for pulling but that doesn't seem like the way to go:

http://wiki.rdiff-backup.org/wiki/index.php/UnattendedRdiff

> You can seperate the backups by giving each system a different account where
> to store the backups.

I'm not sure what you mean.  The backups are all stored on the backup server.

> This way you can also have better control over when to do the backup. If your
> laptop hooks up via VPN just to quickly check email over an expensive or slow
> link, you might not want the backup to start downloading all the pictures you
> took during the holiday or that 300-page manuscript you wrote for your book.
>
> --
> Joost

Here's what I'm doing.  root on 3 machines pushes to non-root on a 4th
machine via rdiff-backup and SSH keys.  The SSH keys are restricted
like so (although there is no from= for the laptop's key since it
could be behind any IP):

command="rdiff-backup
--server",from="12.34.56.78",no-port-forwarding,no-X11-forwarding,no-pty
ssh-rsa ... root@machine1

Is this a good arrangement?  I think the worst-case scenario
(compromised SSH keys) is read/write access of the non-root user on
the backup server via rdiff-backup.

Additionally, the backups on the 4th machine are pushed to another
machine by root to non-root via rsync and SSH keys.  Is there a way to
restrict SSH keys to the rsync command?

Should the non-root backup user have any special configuration?

Can I reserve 0% for root on my USB hard drive which is only used for
backups and does not contain an OS?

- Grant