# Mail Services¶

We provide each of our members with personal emails, as well as the right to create mailing lists through mailman. Our organizational mailing lists (announce, acm, officers, and admins) are all run through mailman as well.

## Member Email¶

Out of a sense of tradition, our mail host is named centaur.vm.acm.jhu.edu and listens on the address mapped to centaur.acm.jhu.edu externally. See Ingress.

### Postfix¶

We run Postfix as our MTA.

#### Blocking Domains¶

The file /etc/postfix/access contains a list of domains to be rejected. At the time of this writing, the only such domain is mms.att.net, from which we recieved a bunch of spam about six hours before the file’s creation. In postman’s main.cf primary config file, you will find the line:

smtpd_sender_restrictions = hash:/etc/postfix/access


This tells postman that in the above-mentioned file it can find a list of domains from which it should not accept mail. To add to the list of domains, you can just edit the file; add the domain and the word REJECT, as in the att.net line, then run:

postmap hash:/etc/postfix/access
systemctl restart postfix


### Mail Volumes¶

#### Patching for AFS¶

This is exciting:

apt-get source postfix
cd postfix-${...} patch -p1 < /afs/acm.jhu.edu/group/admins.pub/postfix-local-afs.diff dpkg-buildpkg # this will take a while! cd .. dpkg --install postfix-${...}


You may wish to look at file:///afs/acm.jhu.edu/group/admins.pub/postfix-local-afs.diff before executing these instructions to see what’s going on in a bit more detail!

## Mailman and the Lists¶

We’re currently running mailman 2.1.18, which has been out of date for only a bit less than two years as of this writing. Mailman (or at least mailman2) is horrifically insecure and somewhat difficult to use. We should probably move to a superior list server, but we would like to port over our archives and current lists, which could take some doing.