Re: [gentoo-user] Finalizing my backup system

[Grant <emailgrant@gmail.com>]

>>>> I'm using backupninja to backup data from my laptop, desktop, and
>>>> remote server onto a remote desktop system.  backupninja is very
>>>> simple and is really just an interface to a few other programs
>>>> including rdiff-backup.  I'm not worried about a good restore method
>>>> for now, I want to focus on keeping it simple and protecting my data.
>>>> This is the first time I've set up a real backup system and I'd love
>>>> to get some advice from you guys.  I've got a few questions.
>>>>
>>>> 1. This is the first time I've used passwordless SSH keys.  root on
>>>> each system being backed up logs into the remote desktop as a normal
>>>> user to store the backups.  Is this pretty safe?  I suppose if root is
>>>> compromised on any of the three systems being backed up (via physical
>>>> access or otherwise), the remote desktop will also be compromised as a
>>>> normal user.  Maybe that normal user should be extraordinarily
>>>> unprivileged?
>>>
>>> You can limit SSH access to only certain commands. On the remote desktop
>>> machine, you probably had to add an entry to the SSH authorized_keys
>>> file. You can prefix that line with the command that the user is allowed
>>> to run. For example (I use rdiff-backup too):
>>>
>>>  command="/usr/bin/rdiff-backup --server",no-pty,no-port-forwarding
>>>  ssh-rsa <big_ugly_key>
>>
>> I tried both that and simplified versions of it but it seems to
>> prevent the login from working.  It hangs on the following command,
>> which works if I don't add the above:
>>
>> ssh  -o PasswordAuthentication=no 1.2.3.4 -l user 'echo -n 1'
>
> That's the point? You can't log in (run /bin/bash) or do anything except
> the command listed in the authorized_keys file.

I see what you're saying but don't I need to use the ssh command in
order to use the rdiff-backup command?

- Grant