I have wanted to get away from Google for quite some time now. The first step, obviously, is switching to DuckDuckGo, but after that things get significantly harder. I needed something to replace Gmail (for obvious reasons) and Google Contacts (as it is quite handy to have the same contact book in your email and your phone). It just so happens my needs were pretty clear this time around:
- email server with my own domain name;
- webmail client with PGP encryption support;
- CardDAV integration, to sync the contacts with my phone (using davx5).
And, while we're at it, some place to host this very website. All of this open source (of course), and with as much control as I can have over it.
You can probably guess how it ended. I just did it myself.
As it turns out, there are FOSS solutions to all of the above, and almost all of them have ready-to-go Docker containers. With the help of nginx, docker-mailserver, Roundcube and Radicale my server was brought to life in a span of a few weeks, totaling maybe two days of total work.
It was overall much easier than I thought it would be, which is always a pleasant surprise. The only part I had some trouble with was obtaining SSL certificates with Certbot, which does have a standalone Docker container, but requires access to host's port 80 to perform the challenges. And, as you can probably guess, port 80 is already occupied by nginx, serving this very website. I was trying to introduce some sort of complex dance, in which nginx would shut itself down while Certbot did it's thing, but ultimately packaging the two in a single container proved to be the easiest and cleanest solution.
After that hiccup it was all smooth sailing, even containerizing Radicale (for which a first party Docker container does not exist) proved to be extremely easy.
Containers and portability
There is a problem with doing all of this yourself - it needs to be reliable. Email is a pretty important thing, and you don't want it to not work. If it fails, you better have a plan to bring it back up to speed as fast as possible.
The thing about containers is that they are portable (it's the reason they exist). Data files are contained in a single directory, which can be automatically tarballed and SCP'd to a backup location, creating a backup every hour (or however often you please). Then, in the event of some failure, I can simply:
- nuke the server (if necessary);
- pull the setup repository from remote (GitHub or Sourcehut);
- untar the backup into the data directory;
docker-compose up -d --build…
…and things are back up and running in ~5 minutes. The same is true for the migration case - changing the VPS provider is as simple as executing steps 2-4, with the addition of changing the IP addresses in DNS records to the new virtual machine.
I want the things I maintain to be reliable and reproducible - in the event I screw things up or my house burns down I want to be able to get my setups up and running as quickly and painlessly as possible, exactly the same as they were before the disaster struck. Containers are awesome for that.
Update - December 2022
The Docker setup worked pretty great, but I have dreamt of something fully declarative, with (ideally) almost no on-server state.
I have thus migrated it to NixOS, which I was toying with for some time on virtual machines and Raspberry Pi. The dream would be to have the server on-premise, perhaps on the aforementioned Raspberry Pi, but this is no easy task - see my rant about Stay-at-Home servers.