Hi,

I have postfix and mysql set up on one server running Ubuntu 6.10. I have to upgrade all them at their current versions and ensuring current email service on line. So, I installed in other machine the current versions of the same programs. The oldest server is the current MTA, the new machine is on line but I don't know where I should make changes that allow me move some mailboxes from one to other. I tried reassigning priorities in them MX's records but it didn't work.

Thanks in advance.

I think you will need to do this in several steps to get it to work properly.

First, you will need to create the users on the new server. Then configure the old server to forward mail to the new server on a per user basis. This can be accomplished with an alias table or with virtual transport. There is lots of information on how to do this in the postfix docs and here is a link to a thread that might help.

After you get the mail going to the new server on a per user basis you should set the old server to forward all mail to the new one as a sanity check. At this same time, adjust the MX priorities in the DNS and set the TTL values to a low value. If you had high TTL values, it may take a while for the changes to take effect, so you might have to leave things like this for a while. After all the mail is coming directly into the new server, then you can safely decommission the old server.