> On Jan 5, 2018, at 6:38 PM, Boris S. <[hidden email]> wrote:
> But I wonder what would be best practice to do a migration of an existing configuration.
> Is it possible to have my original, working setup as a starting point in a new instance?
Yes. The key constraint is that no two instances may share:
* master.cf "inet" entries that resolve to a common [IP:]port
Otherwise, you may clone most of an existing main.cf and master.cf
into a new instance, making sure to not clobber the "multi_instance_..."
parameters, the instance-specific directories, or create overlapping
Doing this on a live system can be a bit tricky if there are already
queued messages, and the role of the default instance changes in a
way that is not appropriate for delivering deferred mail. Draining the
queue during a maintenance window is before switching to multi-instance
is probably simplest.