mailu/INSTALL.md

Installing Freeposte.io

Things to consider

Freeposte.io is working, it has been powering hundreds of e-mail accounts since around January 2016. It is still not massively tested however and you should not run any critical mail server until you have properly tested every feature.

Also, the idea behind Freeposte.io is based on the work by folks from Poste.io. If free software is not the reason you chose Freeposte.io or if you are seeking long-term professional support, you should probably turn to them instead.

Picking a distribution

The mail server runs as a set of Docker containers. It is thus almost agnostic of the underlying operating system as long as a fairly recent Linux kernel is running and the Docker API (>= 1.11) is available.

Because most of our tests run on Debian Jessie and Debian Stretch, we recommend one of these for the base system. Freeposte.io should however be able to run on any of the officially supported distributions.

For the purpose of this guide, all examples are based on Debian Stretch. The differences with other system will hardly be noticeable however.

Setting up the distribution

First, install Debian Stretch from the netinstall CD image. When installing, make sure that you either:

• setup a root ext4 partition,
• or setup a root btrfs partition,
• or leave enough unpartitionned space for a dedicated ext4 or btrfs partition.

If you chose to create a dedicated partition, simply mount it to /var/lib/docker. You could also create a separate partition (ext4 is a sane default) ans mount it to /freeposte for storing e-mail data.

Docker supports AUFS over ext4 and btrfs as stable storage drivers. Other filesystems are supported such as OverlayFS. If you know what you are doing, you should go for it.

Freeposte.io uses Docker port forwarding from the host to make services available to external users. First, your host should have a public IP address configured (see /etc/network/interfaces) or your router should forward connections to its internal IP address. Due to spam problems and reputation services, it is highly recommended that you use a dedicated IP address for your mail server and that you have a dedicated hostname with forward and reverse DNS entries for this IP address.

Also, your host must not listen on ports 25, 80, 110, 143, 443, 465, 587, 993 or 995 as these are used by Freeposte services. Therefore, you should disable or uninstall any program that is listening on these ports (or have them listen on a different port). For instance, on a default Debian install:

apt-get autoremove --purge exim4 exim4-base

Finally, Docker relies heavily on iptables for port forwardings. You should use iptables-persistent (or any equivalent tool on other systems) for managing persistent rules. If you were brave enough to switch to nftables, you will have to rollback until official support is released by Docker or setup your own rulesets.

Setting up Docker

Freeposte.io relies on some of the latest Docker features. Therefore, you should install Docker from the official repositories instead of your distribution ones.

The Docker website is full of detailed instructions about setting up a proper Docker install. Default configuration should be suited for Freeposte.io.

Additionally, you must install docker-compose by following the instructions from the Docker website. Compose is a management tool for Docker, especially suited for multiple containers systems like Freeposte.io.

Once everything is setup, you should be able to run the following commands (exact version numbers do not matter):

$ docker version
Client:
 Version:      1.11.2
 API version:  1.23
 Go version:   go1.6.2
 Git commit:   b9f10c9
 Built:        Sun Jun  5 23:17:55 2016
 OS/Arch:      linux/amd64

Server:
 Version:      1.11.1
 API version:  1.23
 Go version:   go1.6.2
 Git commit:   5604cbe
 Built:        Mon May  2 00:06:51 2016
 OS/Arch:      linux/amd64

$ docker-compose version
docker-compose version 1.7.1, build 6c29830
docker-py version: 1.8.1
CPython version: 3.5.1
OpenSSL version: OpenSSL 1.0.2h  3 May 2016

Preparing the mail server environment

Freeposte.io will store all of its persistent data in /freeposte by default, simply create the directory and move there:

mkdir /freeposte
cd /freeposte

Docker Compose configuration is stored in a file named docker-compose.yml. Additionally, Freeposte.io relies on an environment file for various settings.

Download the templates files from the git repository:

wget https://raw.githubusercontent.com/kaiyou/freeposte.io/master/docker-compose.yml
wget https://raw.githubusercontent.com/kaiyou/freeposte.io/master/freeposte.env

These templates are used for development environment. So, if you do not plan on building Freeposte.io from source, simply remove the build: references:

sed -i '/build:/d' docker-compose.yml

The default configuration will pull the latest image built from the Docker Hub, which is based on the latest commit on GitHub. This behaviour is ok for evaluating Freeposte.io, but you should at least specify a branch. You will still get bugfixes and security updates, but breaking changed will not be pulled unless you explicitely change the branch number. To specify you want to pull the 1.0 branch, simply add the version number to the image field:

VERSION=1.0
sed -i "/image:/s/\(:[0-9.]*\)\?$/:$VERSION/" docker-compose.yml

You should always have all containers using the same branch.

Finally, edit the freeposte.env file and update the following settings:

• set DEBUG to False unless your are debugging,
• set SECRET_KEY to a random 16 bytes string,
• set DOMAIN to your main mail domain,
• set ADMIN to the local part of the admin address on the main domain,
• set HOSTNAME to your mailserver hostname.

Setting up certificates

Freeposte.io relies heavily on TLS and must have a key pair and a certificate available, at least for the hostname configured in freeposte.env.

Create the certificate directory:

mkdir /freeposte/certs

Then create two files in this directory:

• cert.pem contains the certificate,
• key.pem contains the key pair.

Bootstrapping the database

Freeposte.io does not yet have a database initialization or migration system. This will be added in version 1.1. For now, you will have to manually bootstrap the database. First, start the mail server stack:

docker-compose up -d

Then bootstrap the database:

docker exec -i -t freeposte_admin_1 python initdb.py
docker-compose restart

Be very careful and run this command only once, as it will remove any existing data before creating a fresh database.

The default user is admin@example.com with password admin. Connect to the Web admin interface and setup a proper domain with your own admin user before removing the default one:

https://your-host-name.tld/admin/

Testing before going live

You should test all the critical features before using the mail server for actual messages. Try to send and receive e-mails, monitor the logs for some unexpected errors, etc.

Your server should now be running!