I am a self-host of almost everything. I have half a dozen Raspberry Pis, two PCs, and an old thin client that runs most of my digital life. Services range from a Pi-hole with Unbound, fully redundant VPNs, a file server, a Google Photo replacement, Joplin, and a dozen AI services.
I love self-hosting, in all that it entails. However, a recent quick attempt at self-hosting email quickly reminded me why it is a In fact A terrible thing to self-host.
Why self-host an email in the first place?
The temptation to self-host everything is unavoidable
Email, like a phone number, is your gateway to the digital world. You use it to log in to websites, receive important notifications, and communicate personally and professionally.
Every time I think about it, a series of things come to mind that make me want to do it.
- no one reads my email — No vendor scanning messages, no ad profiles created from my inbox, and without AI training.
- No arbitrary limits My storage and domains would be mine.
- No monthly fee — No additional costs besides the server and the domain name.
Despite its appeal, self-hosting email is also a monumental task, probably the hardest thing you can ever self-host. That in itself makes it attractive in a way, a bit like climbing Everest.
Self-hosted email is a pain
Several things must work together perfectly
Most self-hosted services are relatively easy to get up and running. They are usually one, maybe two, services, and often there are all-in-one installation scripts that guide you through every major decision related to the behavior of the service. Email is a very different story.
When I started going through the email self-hosting process again, I quickly remembered that a big part of the difficulty was how many components needed to work together to create a working email. There is:
- The MTA — Handles sending and receiving mail via SMTP.
- The IMAP server — Store your email and let your phone and PC read it.
- Spam filtering (as SpamAssassin) — Try to keep spam and nonsense out of your inbox.
- The authenticator — Secures it together so only you can send and send emails like you.
And then there are some other considerations. You need Sender Policy Framework (SPF) to prevent spoofing, DKIM to cryptographically sign your outgoing mail, and DMARC to handle exceptions.
If you make a mistake, you could completely damage your email or partially breaks your email and it may take you a while to notice.
There are packages like Mailcow, Mail-in-a-box, and Mailu that aim to streamline the process by packaging everything together, but you still face the same fundamental problem: a reliable email requires a bunch of parts that work together seamlessly. Individual parts could fail while others function as they should, which can cause errors that may not be detected at first.
And then on top of that, you need physical hardware that is reliable with extremely Strong backup measures, so you don’t lose any of your emails.
- Storage capacity
-
2 – 26TB
- Workload
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550 TB/year
- Suitable for
-
NAS
Western Digital’s Red Pro NAS hard drives come in sizes ranging from 2TB to 26TB.
Email is very easy to break
You may not even be to blame
Unfortunately, even if you do everything correctly, you are still vulnerable to external forces over which you have no control.
Google, Microsoft and Yahoo cover most of the world’s emails and are famously untrustworthy. other email providers, especially if they originate from an unexpected IP address, and for good reason. Email is a popular vector for all types of cyber attacks.
That could mean they’ll block you from the start. Even if you manage to successfully deliver emails, an episode of “unusual” behavior could result in Google or Microsoft blocking your IP. At that point, you’re stuck, unable to send emails, which almost completely defeats the purpose of self-hosting an email server.
If Navidrome fails, I miss the music; If the email fails, I lose everything
Not only is email difficult to self-host, but the stakes are high. If I lost access to my email, I would lose the ability to log in to dozens of services, recover passwords, and receive 2FA codes. It would be incredibly annoying to fix.
Beyond simple inconveniences, there is also the problem of information loss. If your email server fails and you receive a message, SMTP will try to make sure it is received. eventually. However, that doesn’t solve your immediate problem during an outage: you don’t have access to your email. And a power outage may not even be your fault. Freezing rain could knock out your home email server for hours or even days.
Email is just not worth it
Self-hosting is a great hobby and I’m constantly tempted to try self-hosting an email server just for the experience, if nothing else. However, the difficulty combined with the risk ultimately makes it not worth it.
Managing a reliable email server is a full-time job and I’ll leave it to the professionals.
