A fullstack but simple mail server (SMTP, IMAP, LDAP, Antispam, Antivirus, etc.) using Docker.
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
Brennan Kinney cb6fbf3c58
ci: Allow other workflows to trigger linting (#2220)
6 hours ago
.github ci: Allow other workflows to trigger linting (#2220) 6 hours ago
config example added (#1922) 5 months ago
docs document pre-docker build command (#2164) 22 hours ago
target function _defunc removed (#2199) 4 days ago
test make setup.sh completely non-interactive (#2201) 7 days ago
.all-contributorsrc Update contributors (#2143) 1 month ago
.dockerignore Update check (#1951) 4 months ago
.editorconfig cleaned up >/dev/nulls in Dockerfile and replaced em dashes with normal dashes (#2024) 4 months ago
.gitignore MacOS linting & testing support + docs (#2001) 4 months ago
.gitmodules update bats to latest version 2 years ago
CHANGELOG.md v10.1.2 release (#2156) 1 month ago
CODE_OF_CONDUCT.md docs(fix): Update wiki references to the new docs url 6 months ago
CONTRIBUTORS.md docs(CONTRIBUTORS): update contributors (#2213) 2 days ago
Dockerfile fix: Don't needlessly invalidate cache layers (#2197) 1 week ago
LICENSE Final Migration Step (#6) 8 months ago
Makefile Lock file create and remove improvements (#2183) 2 weeks ago
README.md docs(chore): Normalize for consistency (#2206) 5 days ago
VERSION v10.1.2 release (#2156) 1 month ago
docker-compose.yml docs(chore): Normalize for consistency (#2206) 5 days ago
mailserver.env Change default value of ONE_DIR (#2148) 4 weeks ago
setup.sh Small setup.sh improvements (#2215) 2 days ago

README.md

Docker Mailserver

ci::status docker::pulls documentation::badge

A fullstack but simple mail-server (SMTP, IMAP, LDAP, Antispam, Antivirus, etc.). Only configuration files, no SQL database. Keep it simple and versioned. Easy to deploy and upgrade. Documentation via MkDocs. Why this image was created.

If you have issues, read the full README and the documentation for your version (default is edge) first before opening an issue. The issue tracker is for issues, not for personal support.

  1. Included Services
  2. Issues and Contributing
  3. Requirements
  4. Usage
  5. Examples
  6. Environment Variables
  7. Documentation
  8. Release Notes

Included Services

Requirements

Recommended:

  • 1 Core
  • 2GB RAM
  • Swap enabled for the container

Minimum:

  • 1 vCore
  • 512MB RAM

Note: You'll need to deactivate some services like ClamAV to be able to run on a host with 512MB of RAM. Even with 1G RAM you may run into problems without swap, see FAQ.

Usage

Available Images / Tags - Tagging Convention

CI/CD will automatically build, test and push new images to container registries. Currently, the following registries are supported:

All workflows are using the tagging convention listed below. It is subsequently applied to all images.

Event Ref Image Tags
push refs/heads/master edge
push tag refs/tags/[v]1.2.3 1.2.3, 1.2, 1, latest

Get the tools

Since Docker Mailserver v10.2.0, setup.sh functionality is included within the Docker image. The external convenience script is no longer required if you prefer using docker exec <CONTAINER NAME> setup <COMMAND> instead.

Note: If you're using Docker or Docker Compose and are new to docker-mailserver, it is recommended to use the script setup.sh for convenience.

DMS_GITHUB_URL='https://raw.githubusercontent.com/docker-mailserver/docker-mailserver/master'
wget "${DMS_GITHUB_URL}/docker-compose.yml"
wget "${DMS_GITHUB_URL}/mailserver.env"
wget "${DMS_GITHUB_URL}/setup.sh"

chmod a+x ./setup.sh
./setup.sh help

If no docker-mailserver container is running, any ./setup.sh command will check online for the :latest image tag (the current stable release), performing a pull if necessary followed by running the command in a temporary container.

setup.sh for docker-mailserver version v10.1.x and below

If you're using docker-mailserver version v10.1.x or below, you will need to get setup.sh with a specific version. Substitute <VERSION> with the docker-mailserver release version you're using: wget https://raw.githubusercontent.com/docker-mailserver/docker-mailserver/<VERSION>/setup.sh.

Create a docker-compose environment

  1. Install the latest docker-compose
  2. Edit docker-compose.yml to your liking
    • substitute mail (hostname) and example.com (domainname) according to your FQDN
    • if you want to use SELinux for the ./docker-data/dms/config/:/tmp/docker-mailserver/ mount, append -z or -Z
  3. Configure the mailserver container to your liking by editing mailserver.env (Documentation), but keep in mind this .env file:
    • only basic VAR=VAL is supported (do not quote your values!)
    • variable substitution is not supported (e.g. 🚫 OVERRIDE_HOSTNAME=$HOSTNAME.$DOMAINNAME 🚫)

Get up and running

docker-compose up -d mailserver

# for SELinux, use -Z 
./setup.sh [-Z] email add <user@domain> [<password>]
./setup.sh [-Z] alias add postmaster@<domain> <user@domain>
./setup.sh [-Z] config dkim

If you're seeing error messages about unchecked errors, please verify that you're using the right version of setup.sh. Refer to the Get the tools section and / or execute ./setup.sh help and read the VERSION section.

In case you're using LDAP, the setup looks a bit different as you do not add user accounts directly. Postfix doesn't know your domain(s) and you need to provide it when configuring DKIM:

./setup.sh config dkim domain '<domain.tld>[,<domain2.tld>]'

If you want to see detailed usage information, run ./setup.sh config dkim help.

Miscellaneous

DNS - DKIM

When keys are generated, you can configure your DNS server by just pasting the content of config/opendkim/keys/domain.tld/mail.txt to set up DKIM. See the documentation for more details.

Custom User Changes & Patches

If you'd like to change, patch or alter files or behavior of docker-mailserver, you can use a script. See the documentation for a detailed explanation.

Updating docker-mailserver

Make sure to read the CHANGELOG before updating to new versions, to be prepared for possible breaking changes.

docker-compose pull
docker-compose down
docker-compose up -d mailserver

You should see the new version number on startup, for example: [ TASKLOG ] Welcome to docker-mailserver 10.1.2.

You're done! And don't forget to have a look at the remaining functions of the setup.sh script with ./setup.sh help.

Supported Operating Systems

We are currently providing support for Linux. Windows is not supported and is known to cause problems. Similarly, macOS is not officially supported - but you may get it to work there. In the end, Linux should be your preferred operating system for this image, especially when using this mail-server in production.

Bare Domains

If you want to use a bare domain (hostname == domainname), see FAQ.

Support for Multiple Domains

docker-mailserver supports multiple domains out of the box, so you can do this:

./setup.sh email add user1@docker.example.com
./setup.sh email add user1@mail.example.de
./setup.sh email add user1@server.example.org

SPF/Forwarding Problems

If you got any problems with SPF and/or forwarding mails, give SRS a try. You enable SRS by setting ENABLE_SRS=1. See the variable description for further information.

Ports

See the documentation for further details and best practice advice, especially regarding security concerns.

Mailboxes (aka IMAP Folders)

INBOX is setup by default with the special IMAP folders Drafts, Sent, Junk and Trash. You can learn how to modify or add your own folders (including additional special folders like Archive) by visiting our docs page Customizing IMAP Folders for more information.

Examples

With Relevant Environmental Variables

This example provides you only with a basic example of what a minimal setup could look like. We strongly recommend that you go through the configuration file yourself and adjust everything to your needs. The default docker-compose.yml can be used for the purpose out-of-the-box, see the usage section.

version: '3.8'

services:
  mailserver:
    image: docker.io/mailserver/docker-mailserver:latest
    container_name: mailserver
    hostname: mail
    domainname: example.com
    ports:
      - "25:25"
      - "143:143"
      - "587:587"
      - "993:993"
    volumes:
      - ./docker-data/dms/mail-data/:/var/mail/
      - ./docker-data/dms/mail-state/:/var/mail-state/
      - ./docker-data/dms/mail-logs/:/var/log/mail/
      - ./docker-data/dms/config/:/tmp/docker-mailserver/
      - /etc/localtime:/etc/localtime:ro
    environment:
      - ENABLE_SPAMASSASSIN=1
      - SPAMASSASSIN_SPAM_TO_INBOX=1
      - ENABLE_CLAMAV=1
      - ENABLE_FAIL2BAN=1
      - ENABLE_POSTGREY=1
      - ENABLE_SASLAUTHD=0
      - ONE_DIR=1
      - DMS_DEBUG=0
    cap_add:
      - NET_ADMIN
      - SYS_PTRACE
    restart: always

LDAP setup

version: '3.8'

services:
  mailserver:
    image: docker.io/mailserver/docker-mailserver:latest
    container_name: mailserver
    hostname: mail
    domainname: example.com
    ports:
      - "25:25"
      - "143:143"
      - "587:587"
      - "993:993"
    volumes:
      - ./docker-data/dms/mail-data/:/var/mail/
      - ./docker-data/dms/mail-state/:/var/mail-state/
      - ./docker-data/dms/mail-logs/:/var/log/mail/
      - ./docker-data/dms/config/:/tmp/docker-mailserver/
      - /etc/localtime:/etc/localtime:ro
    environment:
      - ENABLE_SPAMASSASSIN=1
      - SPAMASSASSIN_SPAM_TO_INBOX=1
      - ENABLE_CLAMAV=1
      - ENABLE_FAIL2BAN=1
      - ENABLE_POSTGREY=1
      - ONE_DIR=1
      - DMS_DEBUG=0
      - ENABLE_LDAP=1
      - LDAP_SERVER_HOST=ldap # your ldap container/IP/ServerName
      - LDAP_SEARCH_BASE=ou=people,dc=localhost,dc=localdomain
      - LDAP_BIND_DN=cn=admin,dc=localhost,dc=localdomain
      - LDAP_BIND_PW=admin
      - LDAP_QUERY_FILTER_USER=(&(mail=%s)(mailEnabled=TRUE))
      - LDAP_QUERY_FILTER_GROUP=(&(mailGroupMember=%s)(mailEnabled=TRUE))
      - LDAP_QUERY_FILTER_ALIAS=(|(&(mailAlias=%s)(objectClass=PostfixBookMailForward))(&(mailAlias=%s)(objectClass=PostfixBookMailAccount)(mailEnabled=TRUE)))
      - LDAP_QUERY_FILTER_DOMAIN=(|(&(mail=*@%s)(objectClass=PostfixBookMailAccount)(mailEnabled=TRUE))(&(mailGroupMember=*@%s)(objectClass=PostfixBookMailAccount)(mailEnabled=TRUE))(&(mailalias=*@%s)(objectClass=PostfixBookMailForward)))
      - DOVECOT_PASS_FILTER=(&(objectClass=PostfixBookMailAccount)(uniqueIdentifier=%n))
      - DOVECOT_USER_FILTER=(&(objectClass=PostfixBookMailAccount)(uniqueIdentifier=%n))
      - ENABLE_SASLAUTHD=1
      - SASLAUTHD_MECHANISMS=ldap
      - SASLAUTHD_LDAP_SERVER=ldap
      - SASLAUTHD_LDAP_BIND_DN=cn=admin,dc=localhost,dc=localdomain
      - SASLAUTHD_LDAP_PASSWORD=admin
      - SASLAUTHD_LDAP_SEARCH_BASE=ou=people,dc=localhost,dc=localdomain
      - SASLAUTHD_LDAP_FILTER=(&(objectClass=PostfixBookMailAccount)(uniqueIdentifier=%U))
      - POSTMASTER_ADDRESS=postmaster@localhost.localdomain
      - POSTFIX_MESSAGE_SIZE_LIMIT=100000000
    cap_add:
      - NET_ADMIN
      - SYS_PTRACE
    restart: always