Can't login to IMAP/POP3 server external

Question

I have installed Postfix, Dovecot and MySQL via this tutorial (https://www.linode.com/docs/email/postfix/troubleshooting-problems-with-postfix-dovecot-and-mysql/).

When I do the following command, I get the following response:

$ openssl s_client -connect mail.domain.com:993

* OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE AUTH=PLAIN] Dovecot ready.

I can login to my virtual accounts via the console, but when I'm using this PHP-script, it fails (the page keeps loading).

<?php 
    $mbox = imap_open("{mail.domain.com:993}", "user@domain.com", "password");
?>

When I run the dovecot -n command, I get the following output:

$ dovecot -n

# 2.2.22 (fe789d2): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.4.13 (7b14904)
# OS: Linux 4.4.0-130-generic x86_64 Ubuntu 16.04.3 LTS
auth_debug = yes
auth_verbose = yes
log_path = /var/log/dovecot.log
mail_location = mbox:~/mail:INBOX=/var/mail/%u
mail_privileged_group = mail
namespace inbox {
  inbox = yes
  location =
  mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Sent {
    special_use = \Sent
  }
  mailbox "Sent Messages" {
    special_use = \Sent
  }
  mailbox Trash {
    special_use = \Trash
  }
  prefix =
}
passdb {
  args = /etc/dovecot/dovecot-sql.conf.ext
  driver = sql
}
protocols = imap pop3 lmtp
service auth-worker {
  user = vmail
}
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0666
    user = postfix
  }
  unix_listener auth-userdb {
    mode = 0600
    user = vmail
  }
  user = dovecot
}
service imap-login {
  inet_listener imap {
    port = 0
  }
}
service lmtp {
  unix_listener /var/spool/postfix/private/dovecot-lmtp {
    group = postfix
    mode = 0600
    user = postfix
  }
}
service pop3-login {
  inet_listener pop3 {
    port = 0
  }
}
ssl = required
ssl_cert = </etc/dovecot/private/dovecot.crt
ssl_key = </etc/dovecot/private/dovecot.key
userdb {
  args = uid=vmail gid=vmail home=/var/mail/vhosts/%d/%n
  driver = static
}

I use the firewall 'ufw'.

$ ufw status

Status: active

To                         Action      From
--                         ------      ----
Apache Full                ALLOW       Anywhere
993                        ALLOW       Anywhere
995                        ALLOW       Anywhere
587                        ALLOW       Anywhere
OpenSSH                    ALLOW       Anywhere
Dovecot POP3               ALLOW       Anywhere
Dovecot Secure IMAP        ALLOW       Anywhere
Dovecot Secure POP3        ALLOW       Anywhere
Postfix                    ALLOW       Anywhere
Postfix SMTPS              ALLOW       Anywhere
Postfix Submission         ALLOW       Anywhere
Apache Full (v6)           ALLOW       Anywhere (v6)
993 (v6)                   ALLOW       Anywhere (v6)
995 (v6)                   ALLOW       Anywhere (v6)
587 (v6)                   ALLOW       Anywhere (v6)
OpenSSH (v6)               ALLOW       Anywhere (v6)
Dovecot POP3 (v6)          ALLOW       Anywhere (v6)
Dovecot Secure IMAP (v6)   ALLOW       Anywhere (v6)
Dovecot Secure POP3 (v6)   ALLOW       Anywhere (v6)
Postfix (v6)               ALLOW       Anywhere (v6)
Postfix SMTPS (v6)         ALLOW       Anywhere (v6)
Postfix Submission (v6)    ALLOW       Anywhere (v6)

Is this a firewall problem? It seems like I only can connect from localhost, not from remote.

Thanks in advance.

PS: if you need more information, I'll be happy to share. But I don't know exactly the information you all need for this problem.

Edit: my SMTP server also does not work. I tested it with this (https://www.wormly.com/test-smtp-server) tool.

Output:

Resolving hostname...
Connecting...
Connection: opening to mail.domain.com:25, timeout=300, options=array (
                 )
Connection: opened
SERVER -> CLIENT: 220 mail.domain.com ESMTP Postfix (Ubuntu)
CLIENT -> SERVER: EHLO tools.wormly.com
SERVER -> CLIENT: 250-mail.domain.com
                 250-PIPELINING
                 250-SIZE 10240000
                 250-VRFY
                 250-ETRN
                 250-STARTTLS
                 250-ENHANCEDSTATUSCODES
                 250-8BITMIME
                 250 DSN
CLIENT -> SERVER: STARTTLS
SERVER -> CLIENT: 454 4.7.0 TLS not available due to local problem
SMTP ERROR: STARTTLS command failed: 454 4.7.0 TLS not available due to local problem
2018-07-07 17:06:08 SMTP Error: Could not connect to SMTP host.
CLIENT -> SERVER: QUIT
SERVER -> CLIENT: 221 2.0.0 Bye
Connection: closed
2018-07-07 17:06:08 SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting
Message sending failed.

score 0 · Answer 1 · answered Jul 07 '18 at 17:31

Basically you imap_open() an IMAP stream to a mailbox, do nothing with it and leave it open without imap_close(). As there's nothing to print out, yet the script hasn't finished, empty page keeping loading is expected. You can probably confirm this from mail.log showing the connection. After your imap_open(), try e.g. this from example #2:

$folders = imap_listmailbox($mbox, "{imap.example.org:143}", "*");

if ($folders == false) {
    echo "Call failed<br />\n";
} else {
    foreach ($folders as $val) {
        echo $val . "<br />\n";
    }
}

imap_close($mbox);
?>

Also the SMTP connection from the last test is opened to be closed after STARTTLS. This is definitely not a firewall but a Postfix TLS configuration issue.

It's working indeed. I installed roundcube on my website and the IMAP/POP3 is working. Now I need to figure out the SMTP problem. Thank you for your reply. — yesterday, Jul 07 '18 at 17:48

Can't login to IMAP/POP3 server external

1 Answers1