Re: [Exim] receiver_verify + spam + mailscanner

[2003-10-15] Alan J. Flavell wrote:
> We've certainly discussed the possibility of the secondary MX issuing
> a defer if it knows that the primary is alive: but never quite settled
> on a strategy for doing it - without the risk of some kind of
> ping-pong developing.

In the case where the secondary MX is on a different network than the
primary you can't always make the assumption that if the secondary can
contact the primary then the sender can also.

On several occasions I've seen situations where the route between
a sender and primary MX was not functioning, but email could still be
used to communicate (and investigate the issue) since it was directed
via a third network with functioning routes.

This is a benefit of secondary MX that probably gets overlooked.

--
Lee Maguire <lee@???>