Gentoo Archives: gentoo-user

From: Grant <emailgrant@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Finalizing my backup system
Date: Wed, 06 Oct 2010 21:44:19
Message-Id: AANLkTimL_126647nZxm8n+fb2pK1sa6h1eb7KqA39uHN@mail.gmail.com
In Reply to: Re: [gentoo-user] Finalizing my backup system by Michael Orlitzky
1 >>>> I'm using backupninja to backup data from my laptop, desktop, and
2 >>>> remote server onto a remote desktop system.  backupninja is very
3 >>>> simple and is really just an interface to a few other programs
4 >>>> including rdiff-backup.  I'm not worried about a good restore method
5 >>>> for now, I want to focus on keeping it simple and protecting my data.
6 >>>> This is the first time I've set up a real backup system and I'd love
7 >>>> to get some advice from you guys.  I've got a few questions.
8 >>>>
9 >>>> 1. This is the first time I've used passwordless SSH keys.  root on
10 >>>> each system being backed up logs into the remote desktop as a normal
11 >>>> user to store the backups.  Is this pretty safe?  I suppose if root is
12 >>>> compromised on any of the three systems being backed up (via physical
13 >>>> access or otherwise), the remote desktop will also be compromised as a
14 >>>> normal user.  Maybe that normal user should be extraordinarily
15 >>>> unprivileged?
16 >>>
17 >>> You can limit SSH access to only certain commands. On the remote desktop
18 >>> machine, you probably had to add an entry to the SSH authorized_keys
19 >>> file. You can prefix that line with the command that the user is allowed
20 >>> to run. For example (I use rdiff-backup too):
21 >>>
22 >>>  command="/usr/bin/rdiff-backup --server",no-pty,no-port-forwarding
23 >>>  ssh-rsa <big_ugly_key>
24 >>
25 >> I tried both that and simplified versions of it but it seems to
26 >> prevent the login from working.  It hangs on the following command,
27 >> which works if I don't add the above:
28 >>
29 >> ssh  -o PasswordAuthentication=no 1.2.3.4 -l user 'echo -n 1'
30 >
31 > That's the point? You can't log in (run /bin/bash) or do anything except
32 > the command listed in the authorized_keys file.
33
34 I see what you're saying but don't I need to use the ssh command in
35 order to use the rdiff-backup command?
36
37 - Grant

Replies

Subject Author
Re: [gentoo-user] Finalizing my backup system Michael Orlitzky <michael@××××××××.com>