sending mail to 2 locations

[Harondel J. Sibble]

Is there an easy way in postfix or in MS to send mail to 2 locations?

Situation, isp currently hosts dns and email accounts for client. We have an
internal mailserver with an MS box as the mail relay for the internal server.
We want to test with a few of the accounts that currently exist with the isp,
so the we have the following transport map on the MS box

username1 at domain.com smtp:[192.168.x.x]
username2 at domain.com smtp:[192.168.x.x]
domain.com       smtp:isp mailserver (primary mx for domain)

The plan is to switch the primary MX to the MS box and have isp as secondary
and the MS box will forward the test accounts to the internal server and any
other mail with go to the isp.  Telneting into the MS box, this all works
fine. Now however I am wondering how to have the MS box send mail for the 2
test accounts to both the internal server and isp mailserver.

The reason we are going this way is that we want to keep all the current mail
running as it is while still be able to test and use the internal mailserver
until we are satisfied that it is ready for production use.  Can anyone
suggest a better method of accomplishing the same goal?

--
Harondel J. Sibble
Sibble Computer Consulting
Creating solutions for the small business and home computer user.
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