[Dovecot] mixing virtual and system users

[Ben Morrow]

At  7PM +0200 on 26/05/13 you (Julien Beauviala) wrote:
> 
> I'm setting up a small mail server for aprox 20 users, and I'm trying to
> keep it really simple so I went the virtual users as text file way,
> following this page :
> 
> http://lukas-schulze.de/2012/02/setup-postfix-and-dovecot-on-debian-
> squeeze-with-users-stored-text-file/

While howtos can be useful to see how someone else has solved a similar
problem, they are no substitute for reading and understanding the
documentation yourself.

> It seemed to work fine except for the 'system' users, and I am stumped
> by this. Basically the config does not 'see' /etc/aliases, so mail to
> root or mailman are 'Recipient address rejected: User unknown'.

This sounds like a Postfix rather than a Dovecot problem. It's not clear
which users you mean when you say 'system' users, but I note that your
Postfix 'local' users are not delivered through Dovecot. (This would
require setting either local_transport or mailbox_transport.) Postfix
'virtual mailbox' users don't use /etc/aliases (this is a function of
the local(8) transport) so if you want root at osiris.example.net to go
somewhere sensible you will need to implement that with a Postfix
virtual alias. See the Postfix ADDRESS_CLASS_README.

> I've added the backup pam as explained by the following page* and tried
> many permutations in /etc/postfix/main.cf but still not good, systems
> users are rejected. Obviously something is amiss.

Rejected where? Unless you are talking about SASL auth, this has nothing
to do with Dovecot, and you should ask on a Postfix list.

> * http://wiki2.dovecot.org/Authentication/MultipleDatabases
> 
> If someone could point me in the right direction, that would be great.
> 
> The system is debian 6, details of the configuration below.
> 
> dovecot -n :
> ------------
> # 1.2.15: /etc/dovecot/dovecot.conf

It's a bad idea to set up a new machine with 1.2. The 1.x series is
completely unsupported at this point, so you should really use the
latest 2.1 instead. If you prefer to stick to Debian packages see
http://wiki2.dovecot.org/PrebuiltBinaries#Debian .

[...]
>   userdb:
>     driver: static
>     args: uid=5000 gid=5000 home=/var/vmail/%d/%n allow_all_users=yes
>   userdb:
>     driver: passwd

These two are backwards. Userdb 'static' will always match, so this will
never return user information from /etc/passwd for your system users.

Ben