Authenticate as alias via IMAP (Dovecot / Postfix)
 

Hello,

We are trying to get our IMAP (Dovecot) based webmail client to authenticate the username "user@localdomain.com" as well as any aliases of that user configured in postifx. We can login using the local system user name without the @localdomain.com suffix, but once we add the @localdomain.com to the username the login fails. We are not sure if this is a problem with IMAP, with postfix aliasing, or even the webmail client (roundcube).

Any help would be greatly appreciated. Thanks.

Well you can test each step if you know a little about the protocols--

SMTP - http://qmail.jms1.net/test-auth.shtml (great resource for that particular item)

POP3
IMAP
If you want to post your configs we could likely be of more assistance, but without knowing what you have configured and how it's hard to diagnose and correct any issues that may exist.

I guess I am confused as to what software is handling the login process. I look in roundcube's configuration file and I see a setting for looking up virtual users in postfix:

// Path to a virtuser table file to resolve user names and e-mail addresses
//$rcmail_config['virtuser_file'] = '/etc/postfix/virtusertable';
$rcmail_config['virtuser_file'] = '/etc/aliases';

I also see many functions inside dovecot.conf that would look at the type of login such as:

auth_username_format="%Ld_%Ln"

And there is the aliasing in postfix. I really don't have a clue what I am supposed to be configuring.