Eduardo M KALINOWSKI writes in reesponse to Gandalf Corvotempesta post:

...

I've already read that, and as wrote previously, everything broke down. dovecont -n wasn't able to convert the configuration file and dovecot wasn't started properly. The only way to fix was to downgrade.

As this is a production server, I would like to avoid this kind of issue.....

Set up a server replicating exactly the configuration you have at present. Doesn't need to be anything fancy, a virtual machine is enough. Actually, a virtual machine is a great tool if you can make snapshots and then rollback to known states if any attempt at a change fails.

If you absolutely can't test on a VM or another test host, you can run the new version along side your current version in another installation directory. Configure your new installation to run on alternate ports. You can work off copies of mail data as well if you really want to isolate your test.

Then you can gradually phase in your new version by swapping alternate port/data with production port/data.

Joseph Tam <jtam.home@gmail.com>