[Dovecot] Master User Question

[Marc Perkel]

OK - I'm trying to do weird stuff so rather not answer why I'm doing this.

Trying to log in using a master user:

user at example.com*master at master.com

When debugging the master authenticates - but then it tries to 
authenticate user at example.com and it's not found. And - it is true that 
the user doesn't actually exist.

What I want to do is allow it to log in without checking if the user 
exists, just on the credentials of the master.

I'm not quite understanding what the login attempt for user at example.com 
is trying to do. Is it looking for more necessary information?

Hope I asked this clearly enough. Thanks in advance.