docker-mailserver

A fullstack but simple mail server (smtp, imap, antispam, antivirus...).
Only configuration files, no SQL database. Keep it simple and versioned.
Easy to deploy and upgrade.

Includes:

• postfix with smtp auth
• courier-imap with ssl support
• amavis
• spamassasin
• clamav with automatic updates
• opendkim
• opendmarc (basic setup)
• LetsEncrypt and self-signed certificates
• optional pop3 server (add -e ENABLE_POP3=1 to enable pop3 server)

Why I created this image: Simple mail server with Docker

informations:

• only config files, no *sql database required
• mails are stored in /var/mail/${domain}/${username}
• you should use a data volume container for /var/mail for data persistence
• email login are full email address (username1@my-domain.com)
• user accounts are managed in ./postfix/accounts.cf
• aliases and fowards/redirects are managed in ./postfix/virtual
• antispam rules are managed in ./spamassassin/rules.cf
• files must be mounted to /tmp in your container (see docker-compose.yml template)
• ssl is strongly recommended, read SSL.md to use LetsEncrypt or Self-Signed Certificates
• includes integration tests
• builds automated on docker hub
• dkim public key will be echoed to log. If you have your previous configuration, you can mount volume with it -v "$(pwd)/opendkim":/etc/opendkim"

installation

docker pull tvial/docker-mailserver

build

docker build -t tvial/docker-mailserver .

run

docker run --name mail \
-v "$(pwd)/postfix":/tmp/postfix \
-v "$(pwd)/spamassassin":/tmp/spamassassin \
-v "$(pwd)/letsencrypt/etc":/etc/letsencrypt \
-p "25:25" -p "143:143" -p "587:587" -p "993:993" \
-e DMS_SSL=letsencrypt \
-h mail.domain.com \
-t tvial/docker-mailserver

docker-compose template (recommended)

mail:
  image: tvial/docker-mailserver
  hostname: mail
  domainname: domain.com
  ports:
  - "25:25"
  - "143:143"
  - "587:587"
  - "993:993"
  volumes:
  - ./spamassassin:/tmp/spamassassin/
  - ./postfix:/tmp/postfix/
  - ./letsencrypt/etc:/etc/letsencrypt
  environment:
  - DMS_SSL=letsencrypt

Volumes allow to:

• Insert custom antispam rules
• Manage mail users, passwords and aliases
• Manage SSL certificates

usage

docker-compose up -d mail

client configuration

# imap
username:         <username1@my-domain.com>
password:         <username1password>
server:           <your-server-ip-or-hostname>
imap port:        143 or 993 with ssl (recommended)
imap path prefix:   INBOX
auth method:      md5 challenge-response

# smtp
smtp port:        25 or 587 with ssl (recommended)
username:         <username1@my-domain.com>
password:         <username1password>
auth method:      md5 challenge-response

backups

Assuming that you use docker-compose and a data volume container named maildata, you can backup your user mails like this:

docker run --rm \
--volumes-from maildata_1 \
-v "$(pwd)":/backups \
-ti tvial/docker-mailserver \
tar cvzf /backups/docker-mailserver-`date +%y%m%d-%H%M%S`.tgz /var/mail

todo

Things to do or to improve are stored on Github, some open by myself. Feel free to improve this docker image.

wanna help?

Fork, improve, add tests and PR. ;-)