[Last Call] Learn how to a build a cloud-first strategyRegister Now

  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 487
  • Last Modified:

Copy All Email

Need some ideas here,

We are switching our email system from Postfix to MDaemon.  Both servers are setup with the exact same domain, but currently postfix is the live email server.  

What I would like to do is to be able to have all email entering the postfix server destined for a local address to be copied to the MDaemon server so that they start receiving their emails on both servers.  This way I'd be able to slowly migrate user by user and then just merge their emails from their .pst file to the MDaemon server.

I am trying to avoid just doing a simple one time switch (so I don't have to spend an entire weekend doing this).  

I can't use simple mail forwarding because, like I said, both servers are setup with the same domain name.  Does anyone have any ideas?
  • 3
  • 2
1 Solution
I haven't looked too much into it, but I'm going to be doing something similar to this shortly (postfix to Exchange).  What version of Postfix do you have.  I believe you can just create a transport map file that goes on a per user basis and forwards that email to a different email server.  Of course this means that once you add that user to the transport map they are switched to the other server and no longer receive email from the postfix server.

look at
TheTullAuthor Commented:

That might come in handy,

It looks like I can at least have specific users begin to use MDaemon while others still use Postfix.  This should give me the ability to use both servers side by side so that I don't have to do a "one time changeover".

I am going to look into it a bit further and if does indeed work I will award the points, thanks.
ya, let me know because like I said I need to try to do this exact same thing in about two months.  Just don't have time to work on it for a while though due to other projects going on.
TheTullAuthor Commented:
Working good, thanks for the assistance.

The whole transport map thing was a bit anti-user friendly at first, but became pretty simple.  To get it working all I had to do was edit the following file:


I put the following line in that file

my_address@my_domain.com smtp:[ip_address_of_server]

Then I ran this command:

postmap /etc/postfix/transport

This created a transport.db file.  I then had to enter this line into the main.cf file:

transport maps = hash:/etc/postfix/transport

Then of course I reloaded postfix and all was happy.  Now I just need to do the same thing on my MDaemon server so that I can send messages to internal users that still use the Postfix server...  But I will figure that out on my own, thanks for the help.
no problem, glad to hear it works.  One thing you could do to is keep people (internal users and external MTAs) still using the postfix server since it can route without issue, then just change the pop3 server dns name for the users (since they obviously have different IPs).  Then the postfix should forward the mail to the MDaemon server and that should deliver it to the mailbox.  Once everyone is migrated, you can switch the DNS entry which the client computers will eventually update locally and then everyone will start using the new mail server.  Monitor the postfix server logs to see if anyone legit is still using the postfix server, if no, then shut it down, if yes, find out who and see why they haven't moved yet.

At least this is what I plan on doing.

Featured Post

Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

  • 3
  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now