linuxbashubuntuunixpostfix-mta

Postfix connect to domain.com[74.208.61.85]:587: Connection refused with dovecot, opendkim and SSL


I am trying to follow a tutorial found here, setting up Postfix and dovecot as well as opendkim with SSL on an Ubuntu 22 server.

I am able to get the server to register that the email is being sent, connecting over port 25 with dovecot, but I am unable to send mail due to an error (below):

Aug 21 00:52:55 mamasheen postfix/submission/smtpd[202350]: 0D9B076E8BA: client=localhost[::1], sasl_method=PLAIN, sasl_username=love
Aug 21 00:52:55 mamasheen postfix/cleanup[202358]: 0D9B076E8BA: message-id=<169257917503.194644.17923514880615617174@mamasheen>
Aug 21 00:52:55 mamasheen postfix/qmgr[202220]: 0D9B076E8BA: from=<love@mamasheen.com>, size=1029, nrcpt=1 (queue active)
Aug 21 00:52:55 mamasheen postfix/submission/smtpd[202350]: disconnect from localhost[::1] ehlo=2 starttls=1 auth=1 mail=1 rcpt=1 data=1 quit=1 commands=8
Aug 21 00:52:55 mamasheen postfix/smtp[202359]: connect to mamasheen.com[74.208.61.85]:587: Connection refused
Aug 21 00:52:55 mamasheen postfix/smtp[202359]: 0D9B076E8BA: to=<test-dkwrkck60@srv1.mail-tester.com>, relay=none, delay=0.13, delays=0.01/0.01/0.11/0, dsn=4.4.1, status=deferred (connect to mamasheen.com[74.208.61.85]:587: Connection refused)

I have opened the port and allowed the port in my firewall settings with sudo ufw allow 587/tcp as well as the necessary ufw config for postfix.

Here is my main.cf

# See /usr/share/postfix/main.cf.dist for a commented, more complete version


# Debian specific:  Specifying a file name will cause the first
# line of that file to be used as the name.  The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname

smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
biff = no

# appending .domain is the MUA's job.
append_dot_mydomain = no

# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h

readme_directory = no

# See http://www.postfix.org/COMPATIBILITY_README.html -- default to 3.6 on
# fresh installs.
compatibility_level = 3.6



# TLS parameters
smtpd_tls_cert_file=/etc/letsencrypt/live/mamasheen.com/fullchain.pem
smtpd_tls_key_file=/etc/letsencrypt/live/mamasheen.com/privkey.pem
smtpd_tls_security_level=may

smtp_tls_CApath=/etc/ssl/certs
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache


smtpd_relay_restrictions = permit_sasl_authenticated, defer_unauth_destination
myhostname = mamasheen.com
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = mamasheen.com, localhost, $myhostname
relayhost = mamasheen.com:submission
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
inet_protocols = all

# Milter configuration
milter_default_action = accept
milter_protocol = 6
smtpd_milters = local:opendkim/opendkim.sock
non_smtpd_milters = $smtpd_milters

smtp_tls_security_level = encrypt
smtp_tls_loglevel = 1

And master.cf

#
# Postfix master process configuration file.  For details on the format
# of the file, see the master(5) manual page (command: "man 5 master" or
# on-line: http://www.postfix.org/master.5.html).
#
# Do not forget to execute "postfix reload" after editing this file.
#
# ==========================================================================
# service type  private unpriv  chroot  wakeup  maxproc command + args
#               (yes)   (yes)   (no)    (never) (100)
# ==========================================================================
smtp      inet  n       -       y       -       -       smtpd
#smtp      inet  n       -       y       -       1       postscreen
#smtpd     pass  -       -       y       -       -       smtpd
#dnsblog   unix  -       -       y       -       0       dnsblog
#tlsproxy  unix  -       -       y       -       0       tlsproxy
# Choose one: enable submission for loopback clients only, or for any client.
#127.0.0.1:submission inet n -   y       -       -       smtpd
#submission inet n       -       y       -       -       smtpd
#  -o syslog_name=postfix/submission
#  -o smtpd_tls_security_level=encrypt
#  -o smtpd_sasl_auth_enable=yes
#  -o smtpd_client_restrictions=permit_sasl_authenticated,reject

  -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
  -o smtpd_recipient_restrictions=permit_mynetworks,permit_sasl_authenticated,reject
  -o syslog_name=postfix/submission
  -o smtpd_tls_security_level=encrypt
  -o smtpd_tls_wrappermode=no
  -o smtpd_sasl_auth_enable=yes
  -o smtpd_sasl_type=dovecot
  -o smtpd_sasl_path=private/auth
#  -o syslog_name=postfix/submission
#  -o smtpd_tls_security_level=encrypt
#  -o smtpd_sasl_auth_enable=yes
#  -o smtpd_tls_auth_only=yes
#  -o smtpd_reject_unlisted_recipient=no
#  -o smtpd_client_restrictions=$mua_client_restrictions
#  -o smtpd_helo_restrictions=$mua_helo_restrictions
#  -o smtpd_sender_restrictions=$mua_sender_restrictions
#  -o smtpd_recipient_restrictions=
#  -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
#  -o milter_macro_daemon_name=ORIGINATING
# Choose one: enable smtps for loopback clients only, or for any client.
#127.0.0.1:smtps inet n  -       y       -       -       smtpd
#smtps     inet  n       -       y       -       -       smtpd
#  -o syslog_name=postfix/smtps
#  -o smtpd_tls_wrappermode=yes
#  -o smtpd_sasl_auth_enable=yes
#  -o smtpd_reject_unlisted_recipient=no
#  -o smtpd_client_restrictions=$mua_client_restrictions
#  -o smtpd_helo_restrictions=$mua_helo_restrictions
#  -o smtpd_sender_restrictions=$mua_sender_restrictions
#  -o smtpd_recipient_restrictions=
#  -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
#  -o milter_macro_daemon_name=ORIGINATING
#628       inet  n       -       y       -       -       qmqpd
pickup    unix  n       -       y       60      1       pickup
cleanup   unix  n       -       y       -       0       cleanup
qmgr      unix  n       -       n       300     1       qmgr
#qmgr     unix  n       -       n       300     1       oqmgr
tlsmgr    unix  -       -       y       1000?   1       tlsmgr
rewrite   unix  -       -       y       -       -       trivial-rewrite
bounce    unix  -       -       y       -       0       bounce
defer     unix  -       -       y       -       0       bounce
trace     unix  -       -       y       -       0       bounce
verify    unix  -       -       y       -       1       verify
flush     unix  n       -       y       1000?   0       flush
proxymap  unix  -       -       n       -       -       proxymap
proxywrite unix -       -       n       -       1       proxymap
smtp      unix  -       -       y       -       -       smtp
relay     unix  -       -       y       -       -       smtp
        -o syslog_name=postfix/$service_name
#       -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
showq     unix  n       -       y       -       -       showq
error     unix  -       -       y       -       -       error
retry     unix  -       -       y       -       -       error
discard   unix  -       -       y       -       -       discard
local     unix  -       n       n       -       -       local
virtual   unix  -       n       n       -       -       virtual
lmtp      unix  -       -       y       -       -       lmtp
anvil     unix  -       -       y       -       1       anvil
scache    unix  -       -       y       -       1       scache
postlog   unix-dgram n  -       n       -       1       postlogd
#
# ====================================================================
# Interfaces to non-Postfix software. Be sure to examine the manual
# pages of the non-Postfix software to find out what options it wants.
#
# Many of the following services use the Postfix pipe(8) delivery
# agent.  See the pipe(8) man page for information about ${recipient}
# and other message envelope options.
# ====================================================================
#
# maildrop. See the Postfix MAILDROP_README file for details.
# Also specify in main.cf: maildrop_destination_recipient_limit=1
#
maildrop  unix  -       n       n       -       -       pipe
  flags=DRXhu user=vmail argv=/usr/bin/maildrop -d ${recipient}
#
# ====================================================================
#
# Recent Cyrus versions can use the existing "lmtp" master.cf entry.
#
# Specify in cyrus.conf:
#   lmtp    cmd="lmtpd -a" listen="localhost:lmtp" proto=tcp4
#
# Specify in main.cf one or more of the following:
#  mailbox_transport = lmtp:inet:localhost
#  virtual_transport = lmtp:inet:localhost
#
# ====================================================================
#
# Cyrus 2.1.5 (Amos Gouaux)
# Also specify in main.cf: cyrus_destination_recipient_limit=1
#
#cyrus     unix  -       n       n       -       -       pipe
#  flags=DRX user=cyrus argv=/cyrus/bin/deliver -e -r ${sender} -m ${extension} ${user}
#
# ====================================================================
# Old example of delivery via Cyrus.
#
#old-cyrus unix  -       n       n       -       -       pipe
#  flags=R user=cyrus argv=/cyrus/bin/deliver -e -m ${extension} ${user}
#
# ====================================================================
#
# See the Postfix UUCP_README file for configuration details.
#
uucp      unix  -       n       n       -       -       pipe
  flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
#
# Other external delivery methods.
#
ifmail    unix  -       n       n       -       -       pipe
  flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)
bsmtp     unix  -       n       n       -       -       pipe
  flags=Fq. user=bsmtp argv=/usr/lib/bsmtp/bsmtp -t$nexthop -f$sender $recipient
scalemail-backend unix -       n       n       -       2       pipe
  flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store ${nexthop} ${user} ${extension}
mailman   unix  -       n       n       -       -       pipe
  flags=FRX user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py ${nexthop} ${user}

As well as dovecot config, /etc/dovecot/conf.d/10-master.conf

#default_process_limit = 100
#default_client_limit = 1000

# Default VSZ (virtual memory size) limit for service processes. This is mainly
# intended to catch and kill processes that leak memory before they eat up
# everything.
#default_vsz_limit = 256M

# Login user is internally used by login processes. This is the most untrusted
# user in Dovecot system. It shouldn't have access to anything at all.
#default_login_user = dovenull

# Internal user is used by unprivileged processes. It should be separate from
# login user, so that login processes can't disturb other processes.
#default_internal_user = dovecot

service imap-login {
  inet_listener imap {
    #port = 143
  }
  inet_listener imaps {
    #port = 993
    #ssl = yes
  }

  # Number of connections to handle before starting a new process. Typically
  # the only useful values are 0 (unlimited) or 1. 1 is more secure, but 0
  # is faster. <doc/wiki/LoginProcess.txt>
  #service_count = 1

  # Number of processes to always keep waiting for more connections.
  #process_min_avail = 0

  # If you set service_count=0, you probably need to grow this.
  #vsz_limit = $default_vsz_limit
}

service pop3-login {
  inet_listener pop3 {
    #port = 110
  }
  inet_listener pop3s {
    #port = 995
    #ssl = yes
  }
}

service submission-login {
  inet_listener submission {
    #port = 587
  }
}

service lmtp {
  unix_listener lmtp {
    #mode = 0666
  }

  # Create inet listener only if you can't use the above UNIX socket
  #inet_listener lmtp {
    # Avoid making LMTP visible for the entire internet
    #address =
    #port = 
  #}
}

service imap {
  # Most of the memory goes to mmap()ing files. You may need to increase this
  # limit if you have huge mailboxes.
  #vsz_limit = $default_vsz_limit

  # Max. number of IMAP processes (connections)
  #process_limit = 1024
}

service pop3 {
  # Max. number of POP3 processes (connections)
  #process_limit = 1024
}

service submission {
  # Max. number of SMTP Submission processes (connections)
  #process_limit = 1024
}

service auth {
    unix_listener /var/spool/postfix/private/auth {
      mode = 0660
      user = postfix
      group = postfix
    }
}

service auth-worker {
  # Auth worker process is run as root by default, so that it can access
  # /etc/shadow. If this isn't necessary, the user should be changed to
  # $default_internal_user.
  #user = root
}

service dict {
  # If dict proxy is used, mail processes should have access to its socket.
  # For example: mode=0660, group=vmail and global mail_access_groups=vmail
  unix_listener dict {
    #mode = 0600
    #user = 
    #group = 
  }
}

I also generated keys and set up other files with the following bash code:

sudo cp /etc/postfix/main.cf /etc/postfix/main.cf.backup
sudo cp config/etc_default_opendkim /etc/default/opendkim
sudo cp config/etc_dovecot_conf.d_10-auth.conf /etc/dovecot/conf.d/10-auth.conf
sudo adduser postfix opendkim
sudo mkdir /etc/opendkim
sudo mkdir /etc/opendkim/keys
sudo chown -R opendkim:opendkim /etc/opendkim
sudo chmod go-rw /etc/opendkim/keys
sudo cp config/etc_opendkim.conf /etc/opendkim.conf
sudo echo "*@mamasheen.com     sendonly._domainkey.mamasheen.com" | sudo tee -a /etc/opendkim/signing.table
sudo echo "sendonly._domainkey.mamasheen.com    mamasheen.com:sendonly:/etc/opendkim/keys/mamasheen.com/sendonly.private" | sudo tee -a /etc/opendkim/key.table
sudo echo "127.0.0.1" | sudo tee -a /etc/opendkim/trusted.hosts
sudo echo "localhost" | sudo tee -a /etc/opendkim/trusted.hosts
sudo echo "" | sudo tee -a /etc/opendkim/trusted.hosts
sudo echo "*.mamasheen.com" | sudo tee -a /etc/opendkim/trusted.hosts
sudo chown opendkim:opendkim /etc/opendkim/keys/mamasheen.com/sendonly.private
sudo mkdir /etc/opendkim/keys/mamasheen.com
sudo mkdir /var/spool/postfix/opendkim
sudo chown opendkim:postfix /var/spool/postfix/opendkim
sudo opendkim-genkey -b 2048 -d mamasheen.com -D /etc/opendkim/keys/mamasheen.com -s sendonly -v
sudo systemctl restart postfix

Telnet fails, with command telnet mamasheen.com 587 as well as netstat with netstat -na | grep LISTEN | grep 587. sudo postfix check runs with no comment.

And I configured the domain correctly, with all the right records. I've done this before.

What am I missing here? I followed the tutorial pretty carefully and this is as far as I can get.


Solution

  • Port 587 is the submission protocol in master.cf. You have that disabled. Just remove the comment marker.