This may be off topic -- is it possible to have a different *primary* "hostname" for each ip on a machine?

[William Oliver]

This may not be a "fedora" problem, so if you know where I should ask this,
please let me know.  This is a mail problem, but I suspect that the "real"
problem is named or something else.  I don't know.

OK, here goes.  I have a personal machine that has 5 static ip addresses.  Here's my
hosts file:

% cat hosts

# Automatically generated by OnApp (2.3.3)
127.0.0.1       localhost
50.7.12.26      www.forensicpath.biz forensicpath.biz forensicpath
50.7.12.27      hope.billoblog.com billoblog.com billoblog
50.7.12.28      www.bill-oliver.com bill-oliver.com bill-oliver
50.7.12.29      www.cindyo.net cindyo.net cindyo
50.7.12.30      www.forensicsurveys.com forensicsurveys.com forensicsurveys

Here's some hostname fun:

%hostname
hope.billoblog.com

%hostname -A
forensicpath.biz billoblog.com bill-oliver.com cindyo.net
forensicsurveys.com

%hostname -I
50.7.12.26 50.7.12.27 50.7.12.28 50.7.12.29 50.7.12.30

All of these have virtual hosts wrt apache, though only a couple actually have web pages,
and, it all seems to work well enough, web-wise.

But here's the rub.  I use sendmail for my MTA, and I use billoblog.com as my
SMART_HOST.  Sendmail relays all these domains without a problem, AFAIK.  All the users on
this machine have <user&gt;(a)billoblog.com as their email address except my wife, who
uses &quot;cindy(a)cindyo.net.&quot;

But...  Cindy (my wife, cindy(a)cindyo.net) is having her mail rejected by SuddenLink. If
she sends mail to <user&gt;(a)suddenlink.com, it gets bounced.  The error sent by
SuddenLink is simply "You cannot send email to this domain." Mail will send fine
everywhere else -- aol, verizon, amazon, etc.

Oddly, if *I* send email **from the same machine** as &quot;vendor(a)billoblog.com&quot;,
SuddenLink will accept and deliver the mail.

So, I'm thinking, what's the difference between me sending email as
&quot;vendor(a)billoblog.com&quot; and &quot;cindy(a)cindyo.net&quot; from the same server? 
One is relayed and one is not. The mail is seen by SuddenLink as being delivered by
"hope.billoblog.com," which is my mailserver's hostname.  So, the only thing
I can thing of is that SuddenLink is seeing a relay and assuming it's being spoofed. 
But I don't know -- I called SuddenLink and they had no idea why they were bouncing
the mail, didn't care,  and said that they didn't support personal servers so go
away.

So, I thought, hmmmm...  I wonder if it would be possible to have a different hostname for
different ip addresses?  In other words, could I, on the same machine, serve mail as
"hope.billoblog.com" when the user was &quot;vender(a)billoblog.com&quot; and be
"www.cindyo.net" when the user was &quot;cindy(a)cindyo.net?&quot;

I tried the kneejerk thing of simply adding www.cindyo.net to the
sendmail SMART_HOST, i.e. changing

define(`SMART_HOST', `hope.billoblog.com')dnl

to

define(`SMART_HOST', `hope.billoblog.com:www.cindyo.net')dnl

That just started giving me DNS MX loop errors.


Any pointers?


If there's a postfix fix, I'll happily switch over...

Thanks!

billo