setting up mail forwarding/address rewriting for a home network

[sgordon at kenan.com (Seth Gordon)]

I have three machines at home (horse-nettle, petunia, and eggplant),
all running Linux and sendmail.  I also have a domain (ropine.com),
and an ISP (shore.net) providing virtual hosting and a POP box; one of
my machines (horse-nettle) connects to that ISP with a modem and PPP.

Right now, I can connect to my ISP and then run fetchmail on
horse-nettle, and get all my incoming mail directed to my account on
horse-nettle.  However:

(1) I really want that mail going to my account at petunia; I only
want to use horse-nettle as a firewall, mail server, and news server.

(2) When I try to *send out* mail, sendmail stamps it as being from
sethg at horse-nettle.ropine.com.  The machine at the receiving address,
if it has an ounce of sense, checks the return address, says
"horse-nettle.ropine.com? never heard of them", and rejects the mail.

So what I want is for horse-nettle to properly forward all of my mail
to petunia, and for me to be able to send mail from petunia to the
rest of the Net, and for that mail to get its return address properly
rewritten to [whoever]@ropine.com.[*]  The sendmail documentation has
a few clues, but the forest of how to get this task done is lost in
the trees of individual options and macros, and I've heard so much
about the horrors of sendmail.cf that I'm afraid to just dive in and
change things.

[*]Actually, what I *really* want is to use MX forwarding instead of a
POP box, so my new mail will just get shlurped up every time I
connect, and configure sendmail so that any email with my wife's
address on the envelope will automatically go to
jen at eggplant.ropine.com, but a friend of mine is working on getting
that set up (there are ISP-related complications that are irrelevant
to this note).  Actually, what I *really* *really* want is to have a
permanent connection through DSL or a cable modem, but since we're
hoping to move out of this apartment within a year, it doesn't make
sense to order that now....

--
--Why is it that most kids are attracted to computers while
  most adults are quite wary of computers?
--Most adults are smarter than most kids. ["Ask Uncle Louie"]
== seth gordon == sgordon at kenan.com == standard disclaimer ==
== documentation group, kenan systems corp., cambridge, ma ==


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