ruurtjan / mailserver

config files for a debian mailserver (+ guide)

debian mailserver

notes on setting up a mailserver on debian using postfix, dovecot and rspamd (+ ufw, unbound)

you should (have)

• a clean, updated debian install
• a non-root user
• dns records setup as described in dns-setup.md
• replace example.com in the config files with your domain.tld
• read write-up.md so you actually kind of know what you're doing.

further reading

• https://doc.dovecot.org/
• http://www.postfix.org/documentation.html
• https://rspamd.com/doc/configuration/
• https://wiki.archlinux.org/index.php/Mail_server
• https://wiki.archlinux.org/index.php/Postfix
• https://poolp.org/posts/2019-09-14/setting-up-a-mail-server-with-opensmtpd-dovecot-and-rspamd/
• https://mecsa.jrc.ec.europa.eu/en/postfix

useful tools

• https://www.dmarcanalyzer.com/dkim/dkim-check/
• https://mxtoolbox.com/
• https://ssl-tools.net/mailservers
• https://ssl-tools.net/mails
• https://www.checktls.com/index.html
• https://www.whatsmydns.net/
• https://mecsa.jrc.ec.europa.eu/
• https://www.emailsecuritygrader.com/
• https://en.internet.nl/mail/
• https://tls.imirhil.fr/tls/

other

no guarantees that any of this will work

• i mainly wrote this for myself
• no explanation for why an option is configured that way is provided, ever

todo

• MTA-STS
• DNSSEC
• DANE

backing up your Maildir

the folder needs to be accessible to $SSH_USER for this to work. since mail users are just regular users on the system (and authenticated with pam), you may need to rsync each user's ~/Maildir to a directory which is accessible by $SSH_USER.

rsync -e 'ssh -p $PORT' -avzud --delete $SSH_USER@$IP:/path/to/accessible/Maildir/ ~/Documents/backups/mailbackup/