[Dovecot] Probs authenticating to Dovecot

[Kris Magnusson]

Hi folks. I have set up a Ubuntu 12.04 VM with Dovecot, Postfix, MySQL, amavisd, and ISPConfig 3. The VM has tons of RAM and disk and processor and is permanently connected to the Internet with a static IP. I followed the instructions at howtoforge.com to set up and configure this VM and am using ISPConfig to set up a mail hub for multiple domains. I have the DNS for my other domains' MX records pointing at this host—we'll call it "mail."

Here's the version of Dovecot I'm using:

root at mail:# dovecot --version
2.1.7

Anyway, when I try to connect to my VM and Dovecot using Mail.app on Mountain Lion, I get the following messages in mail.log:

Apr 15 01:18:40 mail postfix/smtpd[4284]: connect from 50-196-170-xxx-static.hfc.comcastbusiness.net[50.196.170.xxx]
Apr 15 01:18:40 mail dovecot: auth-worker(4331): mysql(localhost): Connected to database dbispconfig
Apr 15 01:18:42 mail postfix/smtpd[4284]: warning: 50-196-170-xxx-static.hfc.comcastbusiness.net[50.196.170.xxx]: SASL PLAIN authentication failed: 
Apr 15 01:18:42 mail postfix/smtpd[4284]: disconnect from 50-196-170-xxx-static.hfc.comcastbusiness.net[50.196.170.xxx]
Apr 15 01:18:54 mail dovecot: imap-login: Disconnected (auth failed, 1 attempts in 6 secs): user=<kris>, method=PLAIN, rip=50.196.170.xxx, lip=50.196.170.yyy, TLS, session=<wwn85mHa8AAyxKq9>
Apr 15 01:19:04 mail dovecot: imap-login: Disconnected (auth failed, 1 attempts in 10 secs): user=<kris>, method=PLAIN, rip=50.196.170.xxx, lip=50.196.170.yyy, TLS, session=<XGdT52Ha8QAyxKq9>

But if I run alpine on mail, I can send and receive mail all day long. Here's a log entry that demonstrates this:

Apr 15 01:20:01 mail postfix/smtpd[4284]: connect from localhost[127.0.0.1]
Apr 15 01:20:01 mail postfix/smtpd[4284]: lost connection after CONNECT from localhost[127.0.0.1]
Apr 15 01:20:01 mail postfix/smtpd[4284]: disconnect from localhost[127.0.0.1]
Apr 15 01:20:01 mail dovecot: pop3-login: Disconnected (no auth attempts in 0 secs): user=<>, rip=127.0.0.1, lip=127.0.0.1, secured, session=<FGhS62HaIwB/AAAB>

So I thought it was a problem with SASL not liking PLAIN authentication. When I go to /etc/dovecot and print the contents of dovecot.conf, I see that auth_mechanisms = plain login. 

root at mail:/etc/dovecot# more dovecot.conf
listen = *,[::]
protocols = imap pop3
auth_mechanisms = plain login
disable_plaintext_auth = no
log_timestamp = "%Y-%m-%d %H:%M:%S "
mail_privileged_group = vmail
ssl_cert = </etc/postfix/smtpd.cert
ssl_key = </etc/postfix/smtpd.key
passdb {
  args = /etc/dovecot/dovecot-sql.conf
  driver = sql
}
userdb {
  args = /etc/dovecot/dovecot-sql.conf
  driver = sql
}
plugin {
  quota = dict:user::file:/var/vmail/%d/%n/.quotausage
  sieve=/var/vmail/%d/%n/.sieve
}
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0660
    user = postfix
  }
  unix_listener auth-userdb {
    group = vmail
    mode = 0600
    user = vmail
  }
  user = root
}
protocol imap {
  mail_plugins = quota imap_quota
}
protocol pop3 {
  pop3_uidl_format = %08Xu%08Xv
  mail_plugins = quota
}
protocol lda {
  mail_plugins = sieve quota
}

At this point I'm not sure what to think about this. The mailbox is created, it works on the host, so why wouldn't it work over the network? I've tried frobbing settings in Mail.app, as it does have some wonkiness to it, but no dice. The password is fine, everything is in place, it just doesn't work.

Any thoughts or recommendations?

Thanks,
Kris