Duplicating incoming SMTP traffic
I am looking for a way to duplicate incoming SMTP traffic to two
servers. I want to get the same e-mails at the same time on
two different mail servers. I am in the process of upgrading from Exchange 5.5
to Exchange 2003 and would like to run both servers concurrently while I
have a chance to test multiple mail domains, our third-party mail filter,
etc. This would allow me to address any issues without the possibility
of downtime. Have you ever used or heard of a product that can do this?
The only Exchange facility for doing something like this would be to use
a Forwarding Address where you can send all messages to an address on a
different domain simulating your environment. There is an option on
Forwarding where you can deliver messages to both forwarding address and
mailbox, thereby keeping the primary system working as you want.
Often it is enough to set up your lab to be similar, though not actually
duplicate the actual messages from the live messaging network. If what
you are after is estimating whether your new system can handle the load,
there are tools to let you simulate traffic. In addition to messages
received, such tools can simulate a level of responses to many mailboxes
that you would not be able to fully mimic in a manual test environment.
I should also point out that there are more sophisticated solutions for
data replication and disaster recovery scenarios, but they are complex
This was first published in April 2004