Some background...
I have a slightly odd problem, in that my main outbound mail server is
seemingly being blocked by one of the UK's major budget web/mail hosts.
My postfix logs show things like this:
status=deferred (lost connection with athena.hosts.co.uk[85.233.160.20]
while receiving the initial server greeting)
and a manual test via telnet results in the connection being closed
immediately it's opened:
telnet 85.233.160.20 25
Trying 85.233.160.20...
Connected to 85.233.160.20.
Escape character is '^]'.
Connection closed by foreign host.
I have no idea why they are doing this, as my server isn't listed in any
blocklist that I can find. I suspect it may actually be a configuration
error on their end, but I'm finding it difficult to get in contact there
with someone of sufficient clue to even understand the problem, let
alone resolve it.
I've put in a workaround using transport maps to simply hand off mail
for affected domains to my other mail server (which normally handles
inbound mail), and from there it gets through OK. But that requires an
entry in the transport table for each affected domain, and I keep
encountering new ones - some of which I may only ever need to mail once
or twice and never again!
What I'd like to do, therefore, is set the transport based on the
domain's MX records rather than the domain itself, so that any domain
which uses that company's mail servers will be rerouted to avoid the block.
That doesn't appear to be possible using the transport table itself,
unless I'm misreading the documentation. I could, of course, do it by
adding a local DNS entry to fool my server into sending mail to a
different IP address (that is, make *.hosts.co.uk resolve to my other
mail server), but I'd prefer not to do that as it will affect things
other than mail.
Does anyone have any suggestions?
Mark
--
http://mark.goodge.co.uk
