mailcow: dockerized - 🐮 + 🐋 = 💕

• About mailcow: dockerized
  • Container and volume overview
  • Network
  • FAQ
• Installation
• First steps
  • Rspamd UI access
  • SSL (and: How to use Let's Encrypt)
  • Adjust service configurations
• Useful commands and examples

About mailcow: dockerized

mailcow dockerized comes with 11 containers linked in a mailcow network:

• Dovecot
• Memcached
• Redis
• MySQL
• PowerDNS Recursor
• PHP-FPM
• Postfix
• Nginx
• Rmilter
• Rspamd
• SOGo

4 volumes to keep dynamic data - take care of them!

• vmail-vol-1
• dkim-vol-1
• redis-vol-1
• mysql-vol-1

All configurations were written with security in mind.

Looking for a farm to host your cow?

Container and volume overview

Type	Object name	Network names	External binding	Internal binding	Volumes
Container	postfix-mailcow	${MAILCOW_HOSTNAME}, postfix	25/tcp, 465/tcp, 587/tcp	588/tcp	./data/conf/postfix => /opt/postfix/conf, ./data/assets/ssl => /etc/ssl/mail/:ro
Container	dovecot-mailcow	${MAILCOW_HOSTNAME}, dovecot	110/tcp, 143/tcp, 993/tcp, 995/tcp, 4190/tcp	24/tcp, 10001/tcp	vmail-vol-1 => /var/vmail, ./data/conf/dovecot => /etc/dovecot, ./data/assets/ssl => /etc/ssl/mail/:ro
Container	nginx-mailcow	nginx	443/tcp	80/tcp, 8081/tcp	Mounts from sogo-mailcow, ./data/web => /web:ro, ./data/conf/rspamd/dynmaps => /dynmaps:ro, ./data/assets/ssl/ => /etc/ssl/mail/:ro, ./data/conf/nginx/ => /etc/nginx/conf.d/:ro
Container	pdns-mailcow	pdns	-	53/udp	./data/conf/pdns/ => /etc/powerdns/
Container	rspamd-mailcow	rspamd	-	11333/tcp, 11334/tcp	dkim-vol-1 => /data/dkim, ./data/conf/rspamd/override.d/ => /etc/rspamd/override.d:ro, ./data/conf/rspamd/local.d/ => /etc/rspamd/local.d:ro, ./data/conf/rspamd/lua/ => /etc/rspamd/lua/:ro
Container	mysql-mailcow	mysql	-	3306/tcp	mysql-vol-1 => /var/lib/mysql/, ./data/conf/mysql/ => /etc/mysql/conf.d/:ro
Container	rmilter-mailcow	rmilter	-	9000/tcp	./data/conf/rmilter/ => /etc/rmilter.conf.d/:ro
Container	phpfpm-mailcow	phpfpm	-	9000/tcp	dkim-vol-1 => /data/dkim, ./data/web => /web:ro, ./data/conf/rspamd/dynmaps => /dynmaps:ro
Container	sogo-mailcow	sogo	-	20000/tcp	./data/conf/sogo/ => /etc/sogo/, /usr/lib/GNUstep/SOGo/WebServerResources/
Container	redis-mailcow	redis	-	6379/tcp	redis-vol-1 => /data/
Container	memcached-mailcow	memcached	-	11211/tcp	-
Volume	vmail-vol-1	-	-	-	Mounts to dovecot
Volume	dkim-vol-1	-	-	-	Mounts to rspamd + phpfpm
Volume	redis-vol-1	-	-	-	Mounts to redis
Volume	mysql-vol-1	-	-	-	Mounts to mysql

Network

All containers share a network "mailcow-network" with the subnet 172.22.1.0/24 - if you want to change it, set it in the composer file. IPs are dynamic except for PowerDNS resolver which has a static ip address 172.22.1.254.

FAQ

• rspamd learns mail as spam or ham when you move a message in or out of the junk folder to any mailbox besides trash.
• rspamd auto-learns mail when a high or low score is detected (see https://rspamd.com/doc/configuration/statistic.html#autolearning)
• You can upgrade containers by running docker-compose pull && docker-compose up -d.

Installation

1. You need Docker and Docker Compose. Most systems can install Docker by running wget -qO- https://get.docker.com/ | sh - see this link for installing Docker Compose.

2. Clone this repository and configure mailcow.conf, do not use special chars in passwords in this file (will be fixed soon).

3. docker-compose up -d - leave the -d out for a wall of logs in case of debugging.

Done.

You can now access https://${MAILCOW_HOSTNAME} with the default credentials admin + password moohoo. The database will be initialized when you first visit the UI.

First steps

Rspamd UI access

At first you may want to setup Rspamds web interface which provides some useful features and information.

1. Set a Rspamd controller password:

# Generate hash
docker-compose exec rspamd-mailcow rspamadm pw

2. Replace the default hash in data/conf/rspamd/override.d/worker-controller.inc by your newly generated:

enable_password = "myhash";

3. Restart rspamd:

docker-compose restart rspamd-mailcow

Open https://${MAILCOW_HOSTNAME}/rspamd in a browser and login!

SSL (and: How to use Let's Encrypt)

mailcow dockerized comes with a snakeoil CA "mailcow" and a server certificate in data/assets/ssl. Please use your own trusted certificates.

mailcow uses 3 domain names that should be covered by your new certificate:

• ${MAILCOW_HOSTNAME}
• autodiscover.example.org (used for ActiveSync)
• autoconfig.example.org (used by Thunderbird and derivates)

Obtain multi-SAN certificate by Let's Encrypt This is just an example of how to obtain certificates with certbot. There are several methods!

1. Get the certbot client:

wget https://dl.eff.org/certbot-auto -O /usr/local/sbin/certbot && chmod +x /usr/local/sbin/certbot

2. Disable applications blocking port 80 and run certbot:

cd /path/to/git/clone/mailcow-dockerized
source mailcow.conf
certbot certonly \
	--standalone \
	--standalone-supported-challenges http-01 \
	-d ${MAILCOW_HOSTNAME} \
	-d autodiscover.example.org \
	-d autoconfig.example.org \
	--email you@example.org \
	--agree-tos

3. Create hard links to the full path of the new certificates. Assuming you are still in the mailcow root folder:

mv data/assets/ssl/cert.{pem,pem.backup}
mv data/assets/ssl/key.{pem,pem.backup}
ln $(readlink -f /etc/letsencrypt/live/${MAILCOW_HOSTNAME}/fullchain.pem) data/assets/ssl/cert.pem
ln $(readlink -f /etc/letsencrypt/live/${MAILCOW_HOSTNAME}/privkey.pem) data/assets/ssl/key.pem

4. Restart containers which use the certificate:

docker-compose restart postfix-mailcow
docker-compose restart dovecot-mailcow
docker-compose restart nginx-mailcow

When renewing certificates, run the last two steps (link + restart) as post-hook in a script.

Adjust service configurations

The most important configuration files are mounted from the host into the related containers:

data/conf/
├── dovecot
│   ├── dovecot.conf
│   ├── sieve_after
│   └── sql
│       ├── dovecot-dict-sql.conf
│       └── dovecot-mysql.conf
├── mysql
│   └── my.cnf
├── nginx
│   ├── dynmaps.conf
│   └── site.conf
├── pdns
│   ├── pdns_custom.lua
│   └── recursor.conf
├── postfix
│   ├── main.cf
│   ├── master.cf
│   ├── postscreen_access.cidr
│   ├── smtp_dsn_filter
│   └── sql
|		...
├── rmilter
│   └── rmilter.conf
├── rspamd
│   ├── dynmaps
│   │   ├── settings.php
│   │   └── vars.inc.php -> ../../../web/inc/vars.inc.php
│   ├── local.d
│   │   ├── dkim.conf
│   │   ├── metrics.conf
│   │   ├── options.inc
│   │   ├── redis.conf
│   │   ├── rspamd.conf.local
│   │   └── statistic.conf
│   ├── lua
│   │   └── rspamd.local.lua
│   └── override.d
│       ├── logging.inc
│       ├── worker-controller.inc
│       └── worker-normal.inc
└── sogo
    └── sogo.conf

Just change the according configuration file on the host and restart the related service with docker-compose: docker-compose restart service-mailcow

Useful commands and examples

All commands need to be run from within /path/to/git/clone/mailcow-dockerized.

Update images and restart containers

As easy as:

docker-compose pull
docker-compose up -d

Override used images with custom Dockerfiles

Make your changes in data/Dockerfiles/service and build the image locally:

docker build data/Dockerfiles/service -t andryyy/mailcow-dockerized:service

Now auto-recreate modified containers:

docker-compose up -d

Get bash-completion for docker-compose

For the tab-tab... :-)

curl -L https://raw.githubusercontent.com/docker/compose/$(docker-compose version --short)/contrib/completion/bash/docker-compose -o /etc/bash_completion.d/docker-compose

Logs

You can use docker-compose logs $service-name for almost all containers. Only rmilter does not log to stdout. You can check rspamd logs for rmilter responses.

Run docker-compose logs for all logs at once.

MySQL

Connect to the MySQL database:

source mailcow.conf
docker-compose exec mysql-mailcow mysql -u${DBUSER} -p${DBPASS} ${DBNAME}

Reset mailcow admin to admin:moohoo:

# 1. Drop admin table
source mailcow.conf
docker-compose exec mysql-mailcow mysql -u${DBUSER} -p${DBPASS} ${DBNAME} -e "DROP TABLE admin;"
# 2. Open mailcow UI to auto-init the db

Backup the database:

source mailcow.conf
DATE=$(date +"%Y%m%d_%H%M%S")
docker-compose exec mysql-mailcow mysqldump --default-character-set=utf8mb4 -u${DBUSER} -p${DBPASS} ${DBNAME} > backup_${DBNAME}_${DATE}.sql

Redis

Connect to redis key store:

docker-compose exec redis-mailcow redis-cli

Rspamd:

Rspamd CLI tools:

docker-compose exec rspamd-mailcow rspamc --help
docker-compose exec rspamd-mailcow rspamadm --help

Dovecot:

Run doveadm:

docker-compose exec dovecot-mailcow doveadm

Backup maildir (simple tar file):

docker run --rm -it -v $(docker inspect --format '{{ range .Mounts }}{{ if eq .Destination "/var/vmail" }}{{ .Name }}{{ end }}{{ end }}' $(docker-compose ps -q dovecot-mailcow)):/vmail -v ${PWD}:/backup debian:jessie tar cvfz /backup/backup_vmail.tar.gz /vmail

Remove persistent data

Remove volume mysql-vol-1 to remove all MySQL data. Remove volume redis-vol-1 to remove all Redis data. Remove volume vmail-vol-1 to remove all contents of /var/vmail mounted to dovecot-mailcow. Remove volume dkim-vol-1 to remove all DKIM keys.

Scale it

You can scale some services for mailcow, which is much more useful on a multi-host system. Please do not scale MySQL or Redis containers. This is insufficiently tested!

docker-compose scale rspamd-mailcow=2
docker-compose scale rmilter-mailcow=3
# ...