Hello,

We are in the process of migrating users from one system that is currently not hosted by our company, to our dovecot 2.2.10 installation. We are planning on doing the dovecot dsync command for copying users mail over to the new installation, but the one snag we are running into is ensuring we are able to get the users credentials stored in our system.

We are migrating the email from a Gmail ISP account to our installation as they are discontinuing their support next year. The setup is a multistep process we are hoping to accomplish. When a connection is started to our cluster, it will first check the database to see if the credentials match, if not it will verify against Gmail's servers. If the Gmail test is successful, it would pass the credentials to a script to store them for future login attempts. Once the authentication is verified and stored locally, we would run a post-login script to run dsync to copy the mail down to the new system.

The problem we are running into is efficiently and appropriately hooking into the dovecot authentication process. We are unable to find anything regarding PreLogin Scripting to contrast the PostLoginScripting we are currently using, and the only other thing we are currently seeing as a possible option is running a custom authentication socket or password imap-login to a script. This seems like it would be a resource nightmare depending on the server load and are hoping for a more elegant option to be unveiled.

Any other options or suggestions are welcome. We are also wondering, if we have to go with the custom authentication setup, if there are any examples out there to base our scripts off in setting it up.

Thank you,

Jeremy