🚀 go-pugleaf

heading@breeze.rsre.mod.uk (Anthony J.R. Heading) writes:

> If I want to receive Internet mail, I might attach a machine
> foo.company.uk to the network, and have this as my mail address

> Should I:
>    a) call the machine company.uk instead

You can do this... until you want to set up a second mailserver and share
the load between them, or replace it completely without changing its name.
Then you've got a problem.  Admittedly, the big advantage of this scheme is
that people can finger e-mail addresses and they work.  'talk', too.

>    b) have company.uk as an alias for foo.company.uk

If you mean a CNAME, then return addresses get messed up.  CNAMEs are never
supposed to appear in e-mail addresses, so your mailer will rewrite
user@company.uk to user@foo.company.uk in outgoing mail.

>    c) register company.uk as a name with MX records
>         pointing to foo, then foo-backup, foo-reserve etc

That's what we do here.  It works fine.  I've heard rumors that some
broken mailers only attempt the first MX record in a list, and then give
up, but I've never actually seen this happen.

This scheme loses a little in administration overhead (more nameserver
records), and a little more in that "finger user@company.uk" won't work.  I
really wish it was possible to have FX records.....

-- 
Tom Fitzgerald   Wang Labs       fitz@wang.com   "I went to the universe today;
1-508-967-5278   Lowell MA, USA                   It was closed...."