On Wed, 14 May 1997, Mark Baker wrote:
> It causes a problem if you try to deliver to someone who doesn't have an MX
> record.
Yes, it's been pointed out to me.
> For example a demon customer trying to send mail to digiserve.com
> (to take an example that came up in demon.ip.support.unix recently) will
> first look for an MX for digiserve.com, then when that fails will try
> digiserve.com.demon.co.uk which, because of demon's wildcard MX, succeeds
> but obviously goes to the wrong place.
It is a fact universally acknowledged (or at least, people say it very
often - I saw it again today) that domain expansion is a bad idea
because it leads to problems like this. On the other hand, lots and lots
of sites use it, because it is so very handy for their users.
Replace "domain expansion" with "the use of wildcard MX records" in the
above, and I think it is still true.
When you have a combination of both effects, you can run into even
bigger problems.
Now if we could get the Internet to abolish the rule "look for an A
record if no MX" we might make life a bit better, but pigs will probably
fly to Mars before that happens.
Philip
--
Philip Hazel University Computing Service,
ph10@??? New Museums Site, Cambridge CB2 3QG,
P.Hazel@??? England. Phone: +44 1223 334714
