How to identify where messages come from on a small LAN

[Tony Pursell]

On Sun, 2010-11-28 at 15:50 +0000, Chris G wrote:
> We have a small SoHo LAN with two Ubuntu 10.04 server machines, a backup
> NAS (not running Ubuntu) and two or three desktop machines (some of
> which, being laptops, come and go).
> 
> All mail from anwhere on the LAN is identified as being from the domain
> zbmc.eu because it's behind a NAT router and that's the domain name as
> seen from outside.
> 
> Messages to root, postmaster and other 'system' addresses on all the
> machines are sent to me (chris at zbmc.eu) via settings in the /etc/aliases
> file on each machine.
> 
> So far so good, it all works OK but there is one problem, it's not
> always clear where a status/error mail message has come from because the
> original addressee (root at serverx for example) is changed to
> chris at zbmc.eu by the aliasing.
> 
> Can anyone suggest a way around this problem?
> 
> -- 
> Chris Green
> 

Have you considered aliasing to addresses like root_serverx at zbmc.eu then
configuring your mail system to forward them to you so the mail headers
will show you where they came from?