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I have a setup of mailman with postfix on an ubuntu server 12.04. My problem is that mailing list emails are not forwarded to email addresses external to my institution. However

  • the initial welcome email is received by everyone, internally and externally.
  • in fact, a simple email from command line with mail is successfully sent to anyone
  • after that, mailing list emails are only forwarded to internal addresses.
  • the domain name I'm using for the server is not that of my institution who is hosting the server.

Here is my

#myorigin  = sub.myinstitution.tld
mynetworks = # this is my institution ip range
relayhost = smtp.myinstitution.tld
#inet_interfaces = loopback-only
#local_transport = error:local delivery is disabled
virtual_alias_maps = hash:/etc/postfix/virtual
myhostname = mywebsite.tld
mydestination = $myhostname, localhost.$mydomain, localhost
#relay_domains = $mydestination,

I also found these two links on serverfault and ubuntu forums, but neither of these solutions seem to do the trick for me.

Any help would be much appreciated.

Output of postconf -n:

$ postconf -n
config_directory = /etc/postfix
mydestination = $myhostname, localhost.$mydomain, localhost
myhostname = mywebsite.tld
mynetworks =
myorigin = mywebsite.tld
relayhost = smtp.myinstitution.tld
virtual_alias_maps = hash:/etc/postfix/virtual

I'm not sure what to post for the log. I can't see anything wrong there. This is what happens in /var/log/mail.log when I send a message:

Sep 29 10:23:19 mywebsite postfix/pickup[30113]: 3CD85E4382: uid=10785 from=<myuser>
Sep 29 10:23:19 mywebsite postfix/cleanup[30172]: 3CD85E4382: message-id=<20120929092319.3CD85E4382@mywebsite.tld>
Sep 29 10:23:19 mywebsite postfix/qmgr[30114]: 3CD85E4382: from=<myuser@mywebsite.tld>, size=338, nrcpt=1 (queue active)
Sep 29 10:23:19 mywebsite postfix/smtp[30174]: 3CD85E4382: to=<myuser@myinstitution.tld>, orig_to=<list>, relay=smtp.myinstitution.tld[]:25, delay=0.07, delays=0.04/0/0.01/0.01, dsn=2.0.0, status=sent (250 2.0.0 q8T9Nap1028342 Message accepted for delivery)
Sep 29 10:23:19 mywebsite postfix/qmgr[30114]: 3CD85E4382: removed
share|improve this question
You have to post any log entry containing the string "3CD85E4382". Otherwise it is like "My PC doesn't work. What to do?" – mailq Sep 30 '12 at 21:59
Done, I added everything that contains that string. – gozzilli Oct 1 '12 at 8:47
Your log shows the mail was succesfully sent to smtp.myinstitution.tld . Two op[tions : 1) this mail has been delivered sucessfully to myuser@myinstitution.tld then you have to post logs about an email that has a problem 2) myuser@myinstitution.tld did not receive the mail, then you have to keep on investigating on what happened on smtp.myinstitution.tld, or ask this server administrator. – user130370 Oct 1 '12 at 9:17
It's true that myuser@myinstitution received the email. However, more email addresses are listed on that mailing list and they haven't received the mail (say, nor this shows on the mail log. Does that suggest that it's a mailman configuration problem rather than a postfix one? – gozzilli Oct 1 '12 at 9:59

How does mailman send email ? Does it always use the local sendmail(1) command, or does it also require SMTP to function ?

You have explicitly made SMTP impossible with inet_interfaces = loopback_only.

Please add the output from postconf -n and a log segment showing what goes wrong.

share|improve this answer
I tried commenting out that line, but it still doesn't work. I added more info to the question as you said. Not sure what to put for the log as I can't see anything going wrong. Can you see any other problem? Thanks for your help! – gozzilli Sep 29 '12 at 9:38

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