Apologies if this has already been raised here (which I suspect it has 😊). I tried to raise it as an issue over on github but issues are not enabled for the repository.
The support for mixing virtual users, with fully-qualified email addresses, and system users could be simpler. Assuming it doesn’t mess up other stuff in the code base, of course 😊.
The problem appears to be that the PAM passwd module requires just user names without a domain (which makes sense given that they’re system users) but does not, so far as I can see, support the username_format argument. In my setup, the default structure of 10-auth.conf demonstrates this:
auth_username_format = %n
That means all username arguments lack the domain part…which complicates using fully-qualified ones for virtual users. I realize I could assign arbitrary unique names to the virtual accounts in the lookup file. But that complicates administering the system, so I want to be able to include the domain for virtual users.
After about five hair-pulling hours of wrestling with the configuration I stumbled across an answer utilizing conditionalshttps://serverfault.com/questions/260488/dovecot-user-lookup-fails-when-usin... on ServerFault. It works fine.
But being able to pass a username_format parameter to the PAM module (which I tried, but it was rejected) would be a lot simpler, and a lot more intuitive.
Mark