Search results for "Cannot connect to SMTP server localhost on port 25" - Mailman-users

Re: Held messages not delivered after approval

by Krinetzki, Stephan

Hi Mark, Hi Stephen, so I updated now my configuration a bit. The logging is now default: [logging.archiver] datefmt: %b %d %H:%M:%S %Y [logging.archiver] format: %(asctime)s (%(process)d) %(message)s [logging.archiver] level: info [logging.archiver] path: mailman.log [logging.archiver] propagate: no [logging.bounce] datefmt: %b %d %H:%M:%S %Y [logging.bounce] format: %(asctime)s (%(process)d) %(message)s [logging.bounce] level: info [logging.bounce] path: bounce.log [logging.bounce] propagate: no [logging.config] datefmt: %b %d %H:%M:%S %Y [logging.config] format: %(asctime)s (%(process)d) %(message)s [logging.config] level: info [logging.config] path: mailman.log [logging.config] propagate: no [logging.database] datefmt: %b %d %H:%M:%S %Y [logging.database] format: %(asctime)s (%(process)d) %(message)s [logging.database] level: warn [logging.database] path: mailman.log [logging.database] propagate: no [logging.debug] datefmt: %b %d %H:%M:%S %Y [logging.debug] format: %(asctime)s (%(process)d) %(message)s [logging.debug] level: info [logging.debug] path: debug.log [logging.debug] propagate: no [logging.error] datefmt: %b %d %H:%M:%S %Y [logging.error] format: %(asctime)s (%(process)d) %(message)s [logging.error] level: info [logging.error] path: mailman.log [logging.error] propagate: no [logging.fromusenet] datefmt: %b %d %H:%M:%S %Y [logging.fromusenet] format: %(asctime)s (%(process)d) %(message)s [logging.fromusenet] level: info [logging.fromusenet] path: mailman.log [logging.fromusenet] propagate: no [logging.gunicorn] datefmt: %b %d %H:%M:%S %Y [logging.gunicorn] format: %(t)s "%(r)s" %(s)s %(b)s "%(f)s" "%(a)s" [logging.gunicorn] level: info [logging.gunicorn] path: mailman.log [logging.gunicorn] propagate: no [logging.http] datefmt: %b %d %H:%M:%S %Y [logging.http] format: %(asctime)s (%(process)d) %(message)s [logging.http] level: info [logging.http] path: mailman.log [logging.http] propagate: no [logging.locks] datefmt: %b %d %H:%M:%S %Y [logging.locks] format: %(asctime)s (%(process)d) %(message)s [logging.locks] level: info [logging.locks] path: mailman.log [logging.locks] propagate: no [logging.mischief] datefmt: %b %d %H:%M:%S %Y [logging.mischief] format: %(asctime)s (%(process)d) %(message)s [logging.mischief] level: info [logging.mischief] path: mailman.log [logging.mischief] propagate: no [logging.plugins] datefmt: %b %d %H:%M:%S %Y [logging.plugins] format: %(asctime)s (%(process)d) %(message)s [logging.plugins] level: info [logging.plugins] path: plugins.log [logging.plugins] propagate: no [logging.root] datefmt: %b %d %H:%M:%S %Y [logging.root] format: %(asctime)s (%(process)d) %(message)s [logging.root] level: info [logging.root] path: mailman.log [logging.root] propagate: no [logging.runner] datefmt: %b %d %H:%M:%S %Y [logging.runner] format: %(asctime)s (%(process)d) %(message)s [logging.runner] level: info [logging.runner] path: mailman.log [logging.runner] propagate: no [logging.smtp] datefmt: %b %d %H:%M:%S %Y [logging.smtp] every: $msgid smtp to $listname for $recip recips, completed in $time seconds [logging.smtp] failure: $msgid delivery to $recip failed with code $smtpcode, $smtpmsg [logging.smtp] format: %(asctime)s (%(process)d) %(message)s [logging.smtp] level: info [logging.smtp] path: smtp.log [logging.smtp] propagate: no [logging.smtp] refused: $msgid post to $listname from $sender, $size bytes, $refused failures [logging.smtp] success: $msgid post to $listname from $sender, $size bytes [logging.subscribe] datefmt: %b %d %H:%M:%S %Y [logging.subscribe] format: %(asctime)s (%(process)d) %(message)s [logging.subscribe] level: info [logging.subscribe] path: mailman.log [logging.subscribe] propagate: no [logging.task] datefmt: %b %d %H:%M:%S %Y [logging.task] format: %(asctime)s (%(process)d) %(message)s [logging.task] level: info [logging.task] path: mailman.log [logging.task] propagate: no [logging.vette] datefmt: %b %d %H:%M:%S %Y [logging.vette] format: %(asctime)s (%(process)d) %(message)s [logging.vette] level: info [logging.vette] path: mailman.log [logging.vette] propagate: no Further, I edited the logrotate: /var/log/mailman/mailman-logs/*.log { missingok daily compress delaycompress nomail notifempty rotate 14 dateext su mailman mailman olddir /var/log/mailman/mailman-logs/oldlogs postrotate /bin/kill -HUP `cat /opt/mailman/var/master.pid 2>/dev/null` 2>/dev/null || true # Don't run "mailman3 reopen" with SELinux on here in the logrotate # context, it will be blocked /opt/mailman/mailman-venv/bin/mailman reopen >/dev/null 2>&1 || true endscript } It is now more like the Fedora one and seems to be better. Now in the mailman.log I see the HOLD messages and the approved messages. The smtp.log logs just the incoming Mail, which seems to be fine. So, here a complete Trace: smtp.log: Aug 05 10:18:40 2025 (217984) Available AUTH mechanisms: LOGIN(builtin) PLAIN(builtin) Aug 05 10:18:40 2025 (217984) Peer: ('127.0.0.1', 57074) Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) handling connection Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) >> b'LHLO lists.rwth-aachen.de' Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) >> b'MAIL FROM:<SENDER> SIZE=15187' Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) sender: SENDER Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) >> b'RCPT TO:<stephansmodliste(a)lists.example.com>' Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) recip: stephansmodliste(a)lists.example.com Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) >> b'DATA' Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) >> b'QUIT' Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) connection lost Aug 05 10:18:40 2025 (217984) ('127.0.0.1', 57074) Connection lost during _handle_client() The mailman.log: Aug 05 10:18:40 2025 (217983) HOLD: stephansmodliste(a)lists.example.com post from SENDER held, message-id=<b93e46d8342f42039c99e1d2d036c711@SENDERDOMAIN>: The message is not from a list member Aug 05 10:21:04 2025 (218015) held message approved, message-id: <b93e46d8342f42039c99e1d2d036c711@SENDERDOMAIN> [05/Aug/2025:10:21:04 +0200] "POST /3.1/lists/stephansmodliste(a)lists.example.com/held/211056 HTTP/1.1" 204 0 "-" "GNU Mailman REST client v3.3.5" [05/Aug/2025:10:21:04 +0200] "GET /3.1/lists/stephansmodliste(a)lists.example.com/held?count=0&page=1 HTTP/1.1" 200 90 "-" "GNU Mailman REST client v3.3.5" [05/Aug/2025:10:21:04 +0200] "GET /3.1/lists/stephansmodliste(a)lists.example.com/held?count=10&page=1 HTTP/1.1" 200 90 "-" "GNU Mailman REST client v3.3.5" [05/Aug/2025:10:21:04 +0200] "GET /3.1/lists/stephansmodliste(a)lists.example.com/requests/count?token_owner=moderator HTTP/1.1" 200 73 "-" "GNU Mailman REST client v3.3.5" [05/Aug/2025:10:21:04 +0200] "GET /3.1/lists/stephansmodliste(a)lists.example.com/held/count HTTP/1.1" 200 73 "-" "GNU Mailman REST client v3.3.5" Aug 05 10:21:05 2025 (217986) Cannot connect to SMTP server localhost on port 25 The last error is a very often in the mailman.log: Aug 05 09:46:12 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 09:46:13 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 09:46:13 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 09:46:14 2025 (217987) Cannot connect to SMTP server localhost on port 25 Aug 05 09:46:24 2025 (217987) Cannot connect to SMTP server localhost on port 25 Aug 05 09:50:22 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 09:50:24 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 09:53:30 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 09:55:01 2025 (217987) Cannot connect to SMTP server localhost on port 25 Aug 05 09:55:01 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 09:55:09 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 09:57:44 2025 (217987) Cannot connect to SMTP server localhost on port 25 Aug 05 09:57:46 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 09:58:50 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 09:58:52 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 09:58:52 2025 (217987) Cannot connect to SMTP server localhost on port 25 Aug 05 09:58:53 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 09:58:53 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 09:58:53 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 10:01:18 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 10:02:02 2025 (217987) Cannot connect to SMTP server localhost on port 25 Aug 05 10:07:11 2025 (217987) Cannot connect to SMTP server localhost on port 25 Aug 05 10:10:36 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 10:11:35 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:16:04 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:16:05 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 10:16:07 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:16:58 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 10:17:42 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 10:18:30 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:20:13 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 10:21:05 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:28:08 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:28:08 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 10:28:31 2025 (217987) Cannot connect to SMTP server localhost on port 25 Aug 05 10:28:37 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:28:44 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 10:28:47 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 10:28:50 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:28:57 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 10:29:22 2025 (217988) Cannot connect to SMTP server localhost on port 25 Aug 05 10:29:40 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 10:29:41 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:30:37 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:30:37 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 10:30:50 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:31:15 2025 (217987) Cannot connect to SMTP server localhost on port 25 Aug 05 10:33:42 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:33:53 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:34:27 2025 (217985) Cannot connect to SMTP server localhost on port 25 Aug 05 10:34:28 2025 (217986) Cannot connect to SMTP server localhost on port 25 Aug 05 10:38:25 2025 (230250) Cannot connect to SMTP server lists.example.com on port 25 Aug 05 10:38:25 2025 (230247) Cannot connect to SMTP server lists.example.com on port 25 Even after changing the smtp_host in mailman.cfg this error appears randomly. Sadly the mail does not get delivered. -- Stephan Krinetzki IT Center Gruppe: Anwendungsbetrieb und Cloud Abteilung: Systeme und Betrieb RWTH Aachen University Seffenter Weg 23 52074 Aachen Tel: +49 241 80-24866 Fax: +49 241 80-22134 krinetzki(a)itc.rwth-aachen.de www.itc.rwth-aachen.de Social Media Kanäle des IT Centers: https://blog.rwth-aachen.de/itc/ https://www.facebook.com/itcenterrwth https://www.linkedin.com/company/itcenterrwth https://twitter.com/ITCenterRWTH https://www.youtube.com/channel/UCKKDJJukeRwO0LP-ac8x8rQ -----Original Message----- From: Mark Sapiro <mark(a)msapiro.net> Sent: Tuesday, August 5, 2025 12:51 AM To: mailman-users(a)mailman3.org Subject: [MM3-users] Re: Held messages not delivered after approval On 8/4/25 00:21, Krinetzki, Stephan wrote: >> >> And for every one of those shunted messages there should be an exception with traceback logged in mailman.log. Those tracebacks should be helpful. > > If there were any. Maybe the "debug" level should be "info". But for which logs? The standard logging levels from lowest to highest are debug info warning error critical Whatever level is set for a log results in all messages of that level or higher being logged. I.e. if the log's level is debug, all messages for that log of any level should be logged. For every shunted message, a message like `SHUNTING: <file name without the .pck extention>` preceded by the exception and traceback is logged to error.log with level error. See https://gitlab.com/mailman/mailman/-/blob/master/src/mailman/core/runner.py… > Maybe the restart at night after the lograte maybe the issue. As I said before, blindly restarting Mailman is a bad idea. On servers that I maintain, I always verify that all queues are empty before stopping or restarting Mailman. If necessary, I'll kill the incoming runner and wait for the out queue to empty and then stop mailman. If you want to do this daily, you could automate that., e.g. ``` if queues empty: restart Mailman else: when in queue is empty, sigterm incoming runner when out queue is empty, stop Mailman when Mailman stopped, start Mailman ``` The stop/start is needed because a simple restart at that point won't start the sigtermed incoming runner. -- Mark Sapiro <mark(a)msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan _______________________________________________ Mailman-users mailing list -- mailman-users(a)mailman3.org To unsubscribe send an email to mailman-users-leave(a)mailman3.org https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/ Archived at: https://lists.mailman3.org/archives/list/mailman-users@mailman3.org/message… This message sent to krinetzki(a)itc.rwth-aachen.de

1 year, 3 months

"Cannot connect to SMTP server localhost on port 25"

by Manos Pitsidianakis

Hello, I've been getting "Cannot connect to SMTP server localhost on port 25" from runner "out" in mailman.log over some mails stuck in shunt queue, postfix logs show nothing when this happens, tcpdump on lo interface port 25 shows nothing. The log shows up when I start mailman, and then it seems not to show up again. This is my mailman.cfg's relevant parts: [mta] verp_confirmations: yes verp_personalized_deliveries: yes verp_delivery_interval: 1 incoming: mailman.mta.postfix.LMTP outgoing: mailman.mta.deliver.deliver lmtp_host: localhost lmtp_port: 8024 smtp_host: localhost smtp_port: 25 configuration: python:mailman.config.postfix I can do 'telnet localhost 25' just fine, including as mailman user. I can send and receive mail on my mail server. I tried making a test list and sent/received messages fine. smtp debug logs show "Using agent: <mailman.mta.deliver.Deliver object at 0x7fdd9793c940>" and "IndividualDelivery to: <email(a)address.tld>" on repeat, where the email address is one of the addresses of the shunted mails. version 3.2.2

7 years, 1 month

Incorrect error log message in OutgoingRunner._dispose()

by mailman26＠xse.com

I'm trying to bring up mailman 3 in a spare vm prior to upgrading a production system from mailman 2. One feature the existing mailman 2 lists uses that I can't get working with mailman 3 are templates. After using "mailman import21" I found files with names such as list:member:regular:footer.txt in the list tree. However they were ignored so I removed them I tried tried creating a template using the web postorius gui. When a message is injected, I see an error log from the out runner: Apr 25 12:32:22 2026 (82977) Cannot connect to SMTP server 127.0.0.1 on port 25 Following the error message, the out runner goes cpu bound, creating and deleting queue files in queue/out with .pck and .bak extensions, very quickly. I updated the code to print the exception and it tells a completely different story: Apr 25 12:38:15 2026 (83339) Cannot connect to SMTP server 127.0.0.1 on port 25 (HTTPConnectionPool(host='localhost', port=8000): Max retries exceeded with url: /api/templates/list/test.example.com/list:member:regular:footer (Caused by NewConnectionError("HTTPConnection(host='localhost', port=8000): Failed to establish a new connection: [Errno 61] Connection refused"))) I'm using the default webservice port (8001) so I would not expect anything to ever be listening on 8000. When I stop the runners, the problematic queue file is moved to the shunt queue. Here's what I changed to get the exception detail: mm 287 # pwd /usr/local/lib/python3.11/site-packages/mailman/runners mm 288 # diff -c /var/tmp/outgoing.py outgoing.py *** /var/tmp/outgoing.py Thu Apr 23 14:26:22 2026 --- outgoing.py Sat Apr 25 12:34:33 2026 *************** *** 110,116 **** self._func, msg.get('message-id', 'n/a'))) self._func(mlist, msg, msgdata) self._logged = False ! except socket.error: # There was a problem connecting to the SMTP server. Log this # once, but crank up our sleep time so we don't fill the error # log. --- 110,116 ---- self._func, msg.get('message-id', 'n/a'))) self._func(mlist, msg, msgdata) self._logged = False ! except socket.error as e: # There was a problem connecting to the SMTP server. Log this # once, but crank up our sleep time so we don't fill the error # log. *************** *** 118,125 **** if port == 0: port = 'smtp' # Log this just once. if not self._logged: ! log.error('Cannot connect to SMTP server %s on port %s', ! config.mta.smtp_host, port) self._logged = True return True except SomeRecipientsFailed as error: --- 118,125 ---- if port == 0: port = 'smtp' # Log this just once. if not self._logged: ! log.error('Cannot connect to SMTP server %s on port %s (%s)', ! config.mta.smtp_host, port, e) self._logged = True return True except SomeRecipientsFailed as error:

6 months, 2 weeks

Re: including a template failed

by Wolfgang Bock

Dear Mark, Q: Can you get https://webmail.domain-02.de/mailman3/postorius/api/templates/list/mylist.li sts.domain-03.de/list:member:regular:footer on the Mailman machine? A: No Q: What is your setting for POSTORIUS_TEMPLATE_BASE_URL? A: was: POSTORIUS_TEMPLATE_BASE_URL = 'http://localhost/mailman3/' Changed it to: POSTORIUS_TEMPLATE_BASE_URL = 'https://localhost/mailman3/' Now another problem occurs: Sep 23 22:51:34 2020 (13492) Cannot connect to SMTP server localhost on port 25 HTTPSConnectionPool ... 'localhost' doesn't match either of 'blog.domain-04.de', 'lists.domain-04.de', 'mail.domain-04.de', 'domain-04.de', 'www.domain-04.de'"))) Port 25 entry results from the manual regarding the postfix configuration: https://docs.mailman3.org/projects/mailman/en/latest/src/mailman/docs/mta.ht ml e.g.: [mta] incoming: mailman.mta.postfix.LMTP outgoing: mailman.mta.deliver.deliver lmtp_host: mail.example.com lmtp_port: 8024 smtp_host: mail.example.com smtp_port: 25 Regards Wolfgang -----Ursprüngliche Nachricht----- Von: Mark Sapiro <mark(a)msapiro.net> Gesendet: Sonntag, 20. September 2020 01:05 An: mailman-users(a)mailman3.org Betreff: [MM3-users] Re: including a template failed On 9/19/20 2:47 PM, Wolfgang Bock via Mailman-users wrote: > Hi, > > I created a new mailinglist and got during the test-process the > following errormessage in my mailman.log after: > ... > Sep 19 22:55:08 2020 (1433) ACCEPT: > <000001d68ec7$2553e6e0$6ffbb4a0$(a)domain-01.de> > > Errors: > > Sep 19 22:55:09 2020 (1436) Cannot connect to SMTP server localhost on > port > 25 > HTTPSConnectionPool(host='webmail.domain-02.de', port=443): Max > retries exceeded with url: > /mailman3/postorius/api/templates/list/mylist.lists.domain-03.de/list: > member :regular:footer (Caused by NewConnectionError('<urllib3.connec > tion.VerifiedHTTPSConnection object at 0x7fc8380f1748>: Failed to > establish a new connection: [Errno -2] Name or service not known')) > ... This is wierd. It looks like we are trying to establish a connection to host='webmail.domain-02.de', port=443 in order to GET /mailman3/postorius/api/templates/list/mylist.lists.domain-03.de/list:member :regular:footer, but the error says "Cannot connect to SMTP server localhost on port 25". I have no idea how port 25 is coming into it. Can you get https://webmail.domain-02.de/mailman3/postorius/api/templates/list/mylist.li sts.domain-03.de/list:member:regular:footer on the Mailman machine? What is your setting for POSTORIUS_TEMPLATE_BASE_URL? -- Mark Sapiro <mark(a)msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan _______________________________________________ Mailman-users mailing list -- mailman-users(a)mailman3.org To unsubscribe send an email to mailman-users-leave(a)mailman3.org https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/

6 years, 1 month

Re: Uncaught runner exception

by Stephen J. Turnbull

Wolfgang Bock via Mailman-users writes: > I tested port 25 with swaks ->mail to user on server: localhost > port 25 -> everything fine What is "swaks"? > Apr 07 12:09:21 2020 (28206) Cannot connect to SMTP server > localhost on port 25 Is it possible that Postfix is configured for TLS connections only? If so, it is probably listening on port 465 (the "submissions" port, AKA ssmtp and smtps) or (less likely) 587 (the "submission" port -- no trailing "s"). Mailman needs to be configured correctly for this. See https://mailman.readthedocs.io/en/latest/src/mailman/mta/docs/connection.ht… It's barely possible that Postfix is listening on port 25 but insists on TLS. But that's very unusual, and I think that would produce a SMTP error such as "Need STARTTLS" or "Need SASL" (which happen *after* the TCP connection is established) instead of "Cannot connect" (which suggests a TCP error before a connection is completed). > I have no idea what to do for solving my problems. That's when we're most of service. At least, I hope so! :-) Steve

6 years, 7 months

Re: Incorrect error log message in OutgoingRunner._dispose()

by Mark Sapiro

On April 25, 2026 10:27:06 PM GMT+02:00, Craig Leres via Mailman-users <mailman-users(a)mailman3.org> wrote: > >One feature the existing mailman 2 lists uses that I can't get working with mailman 3 are templates. After using "mailman import21" I found files with names such as list:member:regular:footer.txt in the list tree. However they were ignored so I removed them I tried tried creating a template using the web postorius gui. When a message is injected, I see an error log from the out runner: Did you by chance run import21 as root or another non-mailman user resulting in template files unreadable by Mailman? > Apr 25 12:32:22 2026 (82977) Cannot connect to SMTP server 127.0.0.1 on port 25 This is a well known issue. See <https://gitlab.com/mailman/mailman/-/work_items/582> and related issues referenced therein. >Following the error message, the out runner goes cpu bound, creating and deleting queue files in queue/out with .pck and .bak extensions, very quickly. > >I updated the code to print the exception and it tells a completely different story: > > Apr 25 12:38:15 2026 (83339) Cannot connect to SMTP server 127.0.0.1 on port 25 (HTTPConnectionPool(host='localhost', port=8000): Max retries exceeded with url: /api/templates/list/test.example.com/list:member:regular:footer (Caused by NewConnectionError("HTTPConnection(host='localhost', port=8000): Failed to establish a new connection: [Errno 61] Connection refused"))) > >I'm using the default webservice port (8001) so I would not expect anything to ever be listening on 8000. The default web service port (Postorius and HyperKitty) is 8000. Port 8001 is Mailman core's rest api. -- Mark Sapiro <mark(a)msapiro.net> Sent from my Not_an_iThing with standards compliant, open source software.

6 months, 2 weeks

Re: "Cannot connect to SMTP server localhost on port 25"

by Mark Sapiro

On 9/18/19 11:29 AM, Manos Pitsidianakis wrote: > Hello, > > I've been getting "Cannot connect to SMTP server localhost on port 25" > from runner "out" in mailman.log over some mails stuck in shunt queue, > postfix logs show nothing when this happens, tcpdump on lo interface > port 25 shows nothing. The log shows up when I start mailman, and then > it seems not to show up again. That log message is only written once. It won't be written again unless the out runner is restarted or there is a successful delivery followed by another socket.error. > I can do 'telnet localhost 25' just fine, including as mailman user. I > can send and receive mail on my mail server. I tried making a test list > and sent/received messages fine. Is only one list affected, and is it all messages from this list or only some? > smtp debug logs show "Using agent: <mailman.mta.deliver.Deliver object > at 0x7fdd9793c940>" and "IndividualDelivery to: <email(a)address.tld>" on > repeat, where the email address is one of the addresses of the shunted > mails. Do some deliveries of the problem message succeed? I.e., in the normal case without failure, there will be one "IndividualDelivery to: <email(a)address.tld>" message for each recipient in the recipients list. In the shunted message case, the msgdata object in the shunted pickle contains the recipients. Are there "IndividualDelivery to: <email(a)address.tld>" entries for some but not all recipients. Is the last of these an invalid local address? (Postfix can return a 421 status and drop the connection if there are too many invalid local recipients, although I don't know if this would apply in the VERP case. -- Mark Sapiro <mark(a)msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan

7 years, 1 month

Re: including a template failed

by Mark Sapiro

On 9/19/20 2:47 PM, Wolfgang Bock via Mailman-users wrote: > Hi, > > I created a new mailinglist and got during the test-process the following > errormessage in my mailman.log after: > ... > Sep 19 22:55:08 2020 (1433) ACCEPT: > <000001d68ec7$2553e6e0$6ffbb4a0$(a)domain-01.de> > > Errors: > > Sep 19 22:55:09 2020 (1436) Cannot connect to SMTP server localhost on port > 25 > HTTPSConnectionPool(host='webmail.domain-02.de', port=443): Max retries > exceeded with url: > /mailman3/postorius/api/templates/list/mylist.lists.domain-03.de/list:member > :regular:footer (Caused by NewConnectionError('<urllib3.connec > tion.VerifiedHTTPSConnection object at 0x7fc8380f1748>: Failed to establish > a new connection: [Errno -2] Name or service not known')) > ... This is wierd. It looks like we are trying to establish a connection to host='webmail.domain-02.de', port=443 in order to GET /mailman3/postorius/api/templates/list/mylist.lists.domain-03.de/list:member:regular:footer, but the error says "Cannot connect to SMTP server localhost on port 25". I have no idea how port 25 is coming into it. Can you get https://webmail.domain-02.de/mailman3/postorius/api/templates/list/mylist.l… on the Mailman machine? What is your setting for POSTORIUS_TEMPLATE_BASE_URL? -- Mark Sapiro <mark(a)msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan

6 years, 1 month

Re: Uncaught runner exception

by Wolfgang Bock

Hello Mark, thanks for your hint. Postfix is runnig as mta on my machine. I tested port 25 with swaks ->mail to user on server: localhost port 25 -> everything fine Mailman is configured with localhost for incoming and outgoing mails. After stopping mailman3, deleting all files in the queue directories, restart mailman3 I sent a test-mail /var/log/mailman3/mailman.log Apr 07 12:08:23 2020 (28198) Master started Apr 07 12:08:24 2020 (28206) out runner started. Apr 07 12:08:24 2020 (28202) command runner started. Apr 07 12:08:24 2020 (28203) in runner started. Apr 07 12:08:24 2020 (28200) archive runner started. Apr 07 12:08:24 2020 (28201) bounces runner started. Apr 07 12:08:24 2020 (28210) retry runner started. Apr 07 12:08:25 2020 (28208) rest runner started. Apr 07 12:08:25 2020 (28212) digest runner started. Apr 07 12:08:25 2020 (28205) nntp runner started. Apr 07 12:08:26 2020 (28211) virgin runner started. Apr 07 12:08:26 2020 (28207) pipeline runner started. Apr 07 12:08:26 2020 (28204) lmtp runner started. Apr 07 12:09:19 2020 (28203) ACCEPT: <000f01d60cc4$96c9a8d0$c45cfa70$@[domain]> Apr 07 12:09:21 2020 (28206) Cannot connect to SMTP server localhost on port 25 I have no idea what to do for solving my problems. Regards from Hamburg Wolfgang -----Ursprüngliche Nachricht----- Von: Mark Sapiro <mark(a)msapiro.net> Gesendet: Montag, 6. April 2020 23:50 An: Wolfgang Bock <mailinglisten(a)wbock.de> Betreff: Re: [MM3-users] Re: Uncaught runner exception On 4/6/20 2:44 PM, Wolfgang Bock via Mailman-users wrote: > Thank you Steven for your reply! > > I Set smtp_server to port 25 and got a "Cannot connect ro SMTP Server > on port 25", the former error message didn't show again. > > As I see port 25 is reseved for postfix. So I have to fiddle out how > mailman3 could also use this port for sending mails out. .... You need an MTA for Mailman to deliver its mail to. Normally this will be Postfix, sendmail, Exim, etc running on localhost and listening on port 25. Do you have such an MTA running on localhost? Note, Mailman does not directly send mail to end recipients. It only delivers mail to an outgoing MTA. -- Mark Sapiro <mark(a)msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan

6 years, 7 months

Mailman3 not able to deliver emails sent through list, but moderation notifications

by Daniel Böhmer

Hello Mailman users, I've been using Mailman2 for 10+ years and have recently upgraded to Debian Buster with Mailman3. I've tried to setup Mailman3 similarly but it fails to deliver emails sent through a list. I do receive all moderation notifications at the same time. During startup /var/log/mailman3/mailman.log receives: > Cannot connect to SMTP server localhost on port 25 but I've made sure postfix is listening on *:25 for both IPv4 and IPv6. When sending a message to a list the same file receives: > Nov 25 11:38:14 2022 (70371) ACCEPT: <MESSAGEID@HOST> (message ID and host redacted) and nothing else happens: no more log messages, Postfix logs the email sent TO Mailman but doesn't log anything about emails sent BY Mailman. If Mailman fails to send emails via Postfix I'd expect it to log error messages but it doesn't seem to do so. I found this article stating the the SMTP error message might be misleading: https://blog.tfiu.de/mailman3-cannot-connect-to-smtp-server-localhost-on-po… How to further debug this? What could be wrong with my Mailman3 instance and how to fix it? Kind regards Daniel Böhmer

3 years, 11 months

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