I want to setup my server, have both Linux and a windows box, where
when an email is sent, the IP that shows it being sent is the domain
it is sent from. Right now it shows the servers main IP. Is there a
way to change this through a setting or software? I want this for
purposes of white list and dealing with spam issues, should the arise.

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Request for Question Clarification by maniac-ga on 17 Apr 2006 18:49 PDT

Hello Mdmbud,

Could you explain more fully what you mean by
  "the IP that shows it being sent is the domain it is sent from."?
I ask because there are some mail headers you can manipulate and
others are beyond your control.

There are several headers that include system names / IP addresses.
Using a piece of spam I have as an example, the headers are (sanitized
slightly):

  Return-path: <chvx@globalfinance.nl>
  Received: from mac.com (smtpin09-en2 [10.13.10.79])
   by ms73.mac.com (iPlanet Messaging Server 5.2 HotFix 2.03 (built Nov 22 2004))
   with ESMTP id <0IXH006QYWYBW0@ms73.mac.com> for aaaaaa@mac.com; Mon,
   10 Apr 2006 00:32:35 -0700 (PDT)
[1 - above generated by ms73.mac.com, IP shown is of "mac.com"]
  Received: from cpe-065-188-191-###.triad.res.rr.com
   (cpe-065-188-191-###.triad.res.rr.com [65.188.191.###])
   by mac.com (Xserve/smtpin09/MantshX 4.0) with SMTP id k3A7WRHq020048 for
   <aaaaaa@mac.com>; Mon, 10 Apr 2006 00:32:32 -0700 (PDT)
[2 - above generated by "mac.com", IP shown is of the sending system]
  Received: from rwzbx.awo ([65.188.25.###])
    by cpe-065-188-191-###.triad.res.rr.com (8.13.3/8.13.3)
 with SMTP id k3A7Zped048346; Mon, 10 Apr 2006 03:35:51 -0400
[3 - tentatively the originating site (but may be forged)]
  Date: Mon, 10 Apr 2006 03:30:36 -0400
  From: Sally Mclean <chvx@globalfinance.nl>
[4 - will be listed as "from" in most mail programs]
  Subject: accessible
  To: aaaaaa@mac.com
[5 - remainder deleted]
  
Which of the items (1-4) annotated above are you referring to? [or something else]

If #4, that should be a straight forward fix. This spam example shows
that (from says globalfinance.nl, the bottom received message says
rwzbx.awo) kind of behavior.

If #1 through #3, you can only control the records on the lines you
generate. For example, I "trust" #1 and #2 since they are generated by
mac.com systems. You won't be able to change those lines, and in
particular, can't revise the sending IP of #2.

Lines below that point (e.g., #3) can be manipulated, but that
manipulation will generally be considered "forgery" by the receiving
party.

  --Maniac

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Clarification of Question by mdmbud-ga on 20 Apr 2006 13:13 PDT

Thanks - yes sending IP #2 - but we want to use the IP of the domain
and not the sending server. This way if a client on the server sends
something that has issues, then the server does not get in trouble
only that one client. We are not trying to hide anything, just want
the individual part to be responsible for issues, not server.

Is there a mail server that sends like this?

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Request for Question Clarification by maniac-ga on 23 Apr 2006 18:35 PDT

Hello Mdmbud,

As I noted before, the line I marked as #2 cannot be revised by your
system. Changing mail systems on your side won't do anything to help
this situation.

The problem is that the receiving side generates this line and adds it
to the message. The information used to generate that message is
typically:
 1 the "claimed" host name of the sending system
 2 the actual IP address of the sending system
 3 in some cases, the result of a reverse DNS of the actual IP address
 4 in some cases, a phrase like "possibly forged" if the claimed host
name does not match the reverse DNS result
Only the first and third parts are something you can affect. The other
parts are completely at the control of the receiving system.

The only way you can change the second part (the actual IP of the
sending system) is by using a different server (with a different IP
address) to send the message. I realize this answer won't meet your
stated needs, but perhaps you would consider some alternative
approaches for the "white list and spam issues".

  --Maniac