Re: [gentoo-user] Copying a file via ssh with no password, keeping the system safe

[Willie Wong <wwong@Math.Princeton.EDU>]

On Thu, Oct 07, 2010 at 02:14:47PM -0400, Willie Wong wrote:
> On Thu, Oct 07, 2010 at 06:45:49PM +0200, Momesso Andrea wrote:
> > I need to set up a cron job to transfer a file every day from server A  
> > to server B.
> > 
> > I'd like to do that via ssh and with no user assistance, completely 
> > automated.
> > 
> > Setting up a public key, would do the job, but then, all the  
> > connections between the servers would be passwordless, so if server A  
> > gets compromised, also server B is screwed.
> > 
> > Is there a way to allow only one single command from a single cronjob  
> > to operate passwordless, while keeping all the other connections  
> > secured by a password?
> 
> In the authorized_keys file, you need to include a specification of
> "command=<insert command here>". Which means that on log-in with the
> public key, the sshd will execute that command, and any other commands
> sent from the machine which originated the connection will not
> execute. 
> 
> So I'd imagine you can untar with the command at the target, and
> instead of scp, use something like
> 
>   tar <file> | ssh -i <identity file> user@host
> 

These two links may also be helpful:

http://www.debian-administration.org/articles/438
http://sial.org/howto/rsync/

W
-- 
Willie W. Wong                                     wwong@math.princeton.edu
Data aequatione quotcunque fluentes quantitae involvente fluxiones invenire 
         et vice versa   ~~~  I. Newton