On Thu, Jan 17, 2019 at 11:50:44AM -0200, Silas wrote: > On Wed, Jan 16, 2019 at 07:09:56AM +0530, Mayuresh wrote: > > Since your friend runs multiple lists, may be he has been able to put such > > restriction. Please do share if you can. > > I talked to him. He let it be clear that it is a [ugly?] workaround. > Actually, he wanted to use a mailing list manager, although he agreed that > it might not free the server from the load that happens when someone (like > the university administration) sends an email to 10000+ students.
Thanks, and please convey my thanks to your friend for sharing this! I was tinkering with this idea and came up with my version of ugliness. While I have used postfix to set up simple mail server, I do not have much experience of setting up the kind of things I illustrate below. The documentation is really intimidating and semantics not easy to grasp. This is adopted from /usr/share/examples/postfix/RESTRICTION_CLASS_README main.cf: # `permit' is really my trial and error outcome, most examples show # "reject" there, but that leads to rejection of mails sent to non-list # ids smtpd_recipient_restrictions = ... other things... check_recipient_access hash:/etc/postfix/protected_destinations permit insiders_only = check_sender_access hash:/etc/postfix/insiders smtpd_restriction_classes = insiders_only protected_destinations: <list email id> insiders_only insiders (generatable from the alias list): <member addr 1> OK <member addr 2> OK ... This is kind of working for me, except that when a non-member's email gets rejected, e.g. from gmail, gmail shows "the remote server is misconfigured". The status code is 554 5.7.1, which as per [1] looks ok for the scenario. Firstly why should gmail call it misconfigured, but the bigger worry is it might blacklist the server if this happens too many times! Looking for help on this. Mayuresh [1] https://tools.ietf.org/html/rfc3463