Tony, I think you're missing something here.
ISP's pretty much
always have secondary and tertiary mail servers.
I work part-time for a local ISP. One of the things I've been working
with them on is their email infrastructure.
Interestingly (from the perspective of this conversation), one of the
things they have been considering is dropping their secondary MX. They
see the maintenance cost as higher than the redundancy benefit, and
honestly, I don't think they're wrong. I've never before seen anything
but spamware that gives up as soon as the scheme you outlined.
Actually, I can't think of the last time I've
seen ANY domain that
didn't have more than one MX record.
Which != more than one mailhost. My own, for example, has two MX
records, but they both end up at the same host. (I'll be happy to
explain why - ask me off-list....)
Except for someone trying to run a service out of
their house. To do
so, is... well...
...yes? Is...unacceptable? Is...worth bouncing mail addressed to?
Feel free to drop me from the list if you really feel that I am sinning
that egregiously against the email system by running my own mailserver,
and running only the one. (I won't _like_ it, but it's your list.)
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