On Tue, 10 Jul 2007, Marc Perkel wrote:
> OK - if the second message were from a different IP then it would also
> have to try twice.
Well, there are certain configurations where it won't. At least, not in
the order that you require.
> Tell me about this virtual server feature with shared data. What feature
> is that?
The feature is the ability to select which IP you send from when your
box has more than one. The Exim option is the "interface" option in the
smtp transport, and also the helo_data option, which allows you to
change HELO data. Using these two features, a single instance of Exim
can behave as if it were two separate hosts (as seem by the servers to
which it connects). It might, for example, make this depend on the
domain of the sender's address. However, a single instance of Exim will
have a single set of retry data. So I think it will have problems with
your system:
1. Receive a message from user@domain1
2. Connect to your first MX from IP address for senders in domain1
3. You give a temporary error
4. Connect to your second MX from IP address for senders in domain1
5. Message is accepted
6. Receive a message from user@domain2
7. Your first MX has not yet reached its retry time, so don't use it
8. Connect to your second MX from IP address for senders in domain2
If the IP addresses for domain1 and domain2 are not the same, this will
not work, as I understand your description.
There *are* sites that are configured like this. Not, I suspect, very
many, but I believe they do exist.
--
Philip Hazel University of Cambridge Computing Service
Get the Exim 4 book: http://www.uit.co.uk/exim-book
