[Exim] Config Question

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Hello All,

New to Exim, new to sendmail even.

I've got numerous servers behind a firewall used in a development
environment. None have valid domain names, so sending out email to my
company's system fails on reverse lookup. I'm looking to Exim as a solution,
as I don't want to make valid DNS entries for each machine, as they can
change weekly.

Right now, I have the systems successfully relaying through the server
running Exim v. 4.05 on Solaris 9, running as a replacement for sendmail (I
simply moved /usr/lib/sendmail and created a symbolic link to the Exim
binary, then modified /etc/init.d/sendmail, changing SERVER_PID_FILE to
"/var/spool/exim/exim-daemon.pid"). Exim is running as exim:exim.

Below are what I believe to be the crucial variables in the Exim config
file, with my comments/questions noted per line:

primary_hostname = fogbox.com
I'm using this because it's valid. It differs from the FQDN of the Exim
server, however, which is fgru452g.fgr.kpmgbsc.net

domainlist local_domains = @
My understanding is that this is how I specify which domain Exim treats as
local mail (e.g., delivery of mail @ [the localhost] isn't routed)?

domainlist relay_to_domains = fgr.kpmgbsc.net
I only want to relay mail from my servers behind the firewall, all of which
are on fgr.kpmgbsc.net. Is this correct?

hostlist relay_from_hosts = 127.0.0.1 : 172.16.0.0/12
And I only want to relay from hosts within the private range of 172.16.0.0
to 172.31.255.255. This is where my, erm, lack of knowledge shows.... Is the
netmask correct?

never_users = root
And, let my local alias file (pointing root mail to my real email address)
handle root email...

begin rewrite
*@*fgr.kpmgbsc.net server@??? Ffrs
Here's where (I think) my problem starts. Yes, it works. Yes, it rebadges
the FROM: header with "Super-User [server@???]". But, that's a rather
nebulous return address (not that email will be replied to in our
development environment). I would much prefer that the FROM header be
rewritten so that the reply address contains the hostname such as
"username@??? [server@???]". Any tips on how to make
this happen or other ideas? What's driving me is that my developers want to
fire out all sorts of email from within applications (both Solaris-based and
Windows-based) and I'd like to be able to identify at a glance which
server's the emails are coming from... Of course, one major issue is that
all root email from all servers is rebadged too, which I definitely can't
have unless the aforementioned solution is implemented...

I'd sure appreciate your help! Thanks in advance...

Chris Brewer

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