Migrate from Google Apps to Postfix/Dovecot/RoundCube running on the droplet?
We're currently using Google Apps to handle our emails, since my knowledge in mail server set-up is limited and we needed to set-up e-mail accounts quickly. After some consideration we want to move towards using our own mail server, since GA isn't very cost effective when the number of accounts grow.
So I was planning on setting up Postfix, Dovecot and RoundCube and migrate all our email accounts to be managed on our Ubuntu (nginx webserver) droplet.
The problem is that we don't want to have some downtime on our emails while migrating so I wonder what we can do to reroute mails while setting up the mail server and client on the droplet? So that emails don't go missing during migration. And also what would be the best way to go from Google Apps powered email to our own mail server?
Thanks in advance!