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I've had a Postfix server running for a very short amount of time, and it worked, but I had to restart the server today, and I'm no longer receiving e-mails from external sources:

Jan 23 01:34:44 myservername postfix/smtpd[1055]: connect from db3ehsobe006.messaging.microsoft.com[]
Jan 23 01:34:45 myservername postfix/smtpd[1055]: warning: connect to Connection refused
Jan 23 01:34:45 myservername postfix/smtpd[1055]: warning: problem talking to server Connection refused
Jan 23 01:34:46 myservername postfix/smtpd[1055]: warning: connect to Connection refused
Jan 23 01:34:46 myservername postfix/smtpd[1055]: warning: problem talking to server Connection refused
Jan 23 01:34:46 myservername postfix/smtpd[1055]: NOQUEUE: reject: RCPT from db3ehsobe006.messaging.microsoft.com[]: 451 4.3.5 Server configuration problem; from=<MyKnownWorking@EmailAccountOutside> to=<MyAccount@MyDomain.com> proto=ESMTP helo=<db3outboundpool.messaging.microsoft.com>

The server is listening on port 100023, but I noticed it's only listening via IPv6:

sudo netstat -a | grep 10023
tcp6       0      0 ip6-localhost:10023     [::]:*                  LISTEN

I have no firewall rules in place that would deny that would specific port, hell, I went ahead and flushed the rule set just to confirm it. Here's the output of my postconf -n (I edited out my domain name in place of "mydomain.com":

sudo postconf -n
alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
    append_dot_mydomain = no
biff = no
broken_sasl_auth_clients = yes
config_directory = /etc/postfix
content_filter = amavis:[]:10024
disable_vrfy_command = yes
inet_interfaces = all
inet_protocols = ipv4
mailbox_size_limit = 0
message_size_limit = 0
mydestination = localhost.$mydomain, localhost, mail.mydomain.com, servername.mydomain.com
mynetworks = [::ffff:]/104 [::1]/128
mynetworks_style = host
myorigin = /etc/mailname
readme_directory = no
receive_override_options = no_address_mappings
recipient_delimiter = +
relayhost =
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
smtp_use_tls = yes
smtpd_banner = mail.mydomain.com ESMTP $mail_name
smtpd_delay_reject = yes
smtpd_helo_required = yes
smtpd_recipient_restrictions = reject_unauth_pipelining, permit_mynetworks, permit_sasl_authenticated, reject_non_fqdn_recipient, reject_unknown_recipient_domain, reject_unauth_destination, check_policy_service inet:, permit
smtpd_sasl_auth_enable = yes
smtpd_sasl_local_domain =
smtpd_sasl_security_options = noanonymous
smtpd_sender_restrictions = permit_sasl_authenticated, permit_mynetworks, warn_if_reject reject_non_fqdn_sender, reject_unknown_sender_domain, reject_unauth_pipelining, permit
smtpd_tls_cert_file = /etc/ssl/private/mail.mydomain.com.crt
smtpd_tls_key_file = /etc/ssl/private/mail.mydomain.com.key
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtpd_use_tls = yes
virtual_alias_maps = mysql:/etc/postfix/maps/alias.cf
virtual_gid_maps = static:5000
virtual_mailbox_base = /var/spool/mail/virtual
virtual_mailbox_domains = mysql:/etc/postfix/maps/domain.cf
virtual_mailbox_limit = 0
virtual_mailbox_maps = mysql:/etc/postfix/maps/user.cf
virtual_uid_maps = static:5000

As you can see, I'm even trying to specify via inet_protocols that it listens on ipv4 connections. I've tried it with and without that command.

Any help in troubleshooting would be greatly appreciated! And of course, if you see anything in my configuration is glaringly stupid, I am not above advice or criticism.

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3 Answers 3

up vote 1 down vote accepted

Your last check on smtpd_recipient_restrictions uses a policy service to verify the recipient. Typically this is a postgrey service and appears to have some problems with Postfix connecting to it.

smtpd_recipient_restrictions = ...,check_policy_service inet:, permit

If you remove check_policy_service inet: from the smtpd_recipient_restrictions, you should eliminate the error, but you still should determine what happen to your postgrey or other service that would be running here.

Checking for Postgrey on an Unbuntu System

Typically a postgrey default config will listen on port 10023 for connections and determine if they should be allowed or rejected. Some pieces on an Unbutu server that you can check for to see if this is installed are...

  • Do you have a /etc/default/postgrey file? This is the basic config file.
  • Do you have a /etc/postgrey folder? This is where you can whitelist elements.
  • When you run > which postgrey does it find a binary? Mine is found in /usr/sbin/postgrey.
  • Do you have a /etc/init.d/postgrey script for starting it up on boot up? This is the typical location for Ubuntu daemons.

These will only give you some clues as to if this server may have had postgrey configured at one time. You will need to look further for troubleshooting if the process is not running properly on your server.

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It's interesting, in the postconf -n it shows, however, in my my.cnf it shows as commented out: #smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject Edit: Never mind, I'm dumb. Earlier version commented out. –  DavisTasar Jan 23 '13 at 2:04
I also should add that, that change did work and I am receiving mail now. Would you have any recommendations as to how to determine what about this check_policy_service is having issues with? –  DavisTasar Jan 23 '13 at 2:08
Typically this is a postgrey service integrated with Postfix that will run on this port. You can look for some clues to see if this is installed. Up above is some guidance on checking for Postgrey. –  Tim Koscielski Jan 23 '13 at 21:42
Tim, sir, you are the man. I'll be looking into everything. Postgrey is definitely installed, I ran into a locking issue with it earlier today. –  DavisTasar Jan 24 '13 at 1:58

Davis - you're right, postgrey was changed in 12.04LTS to work in IPv6. Upgrade doesn't change it for postfix and doesn't alert you to make a change.

So you have to do it yourself. Change this:

check_policy_service inet:


check_policy_service inet:::1:10023

in your /etc/postfix/master.cf file, then restart postfix:

sudo service postfix restart

It will allow postfix to talk IPv6 to postgrey.

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Actually, you are not forced to use ipv6, you may set Postgrey and Postfix to ipv4. The problem is, Postgrey (probably version 1.33 and newer) refuse to start on ipv4 localhost ip, so you may use your ethX ip address.

In /etc/postfix/main.cf change this:

check_policy_service inet:


check_policy_service inet:<your_ipv4_address>:10023

Then restart Postfix:

sudo service postfix restart

In /etc/default/postgrey change this:

POSTGREY_OPTS="--inet=10023 --delay=60"


POSTGREY_OPTS="--inet=<your_ipv4_address>:10023 --delay=60"

Then restart Postgrey:

sudo service postgrey restart

Very userful was this Debian mail list message:


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