I need to run my own email server for some of my domains, because the providers that I usually use don’t support them (they use Unicode characters, and not everyone supports that yet). I have a small VPS that I run a few Docker containers on, and I’m wanting to try and run an email server on it as well. What containers are good for a low-hassle email setup? I don’t need a mailbox webui (ex: round cube), but it would be nice to have a UI for management. I do need multi-domain support, however.
Mailcow-dockerized. I’ve used it for nearly a decade, it’s been flawless. Very easy to set up with the admin webpage and has a webmail client, or use Roundcube with it.
Make sure you have your DKIM, SPF and Dmarc records in order and tested against MXtoolbox before you start.
What happens if your server is offline and an email comes in? I’m genuinely curious what it would do. Or must you VPS host your mail server for maximum uptime?
The other server sends again until it times out? Never been an issue, that’s just how email works. Most SMTP servers will attempt for a few days if they know the MX is valid. Besides, I’ve never been out for longer than an hour or two.
All MTAs have retries baked in, so running a self-hosted email server that receives mail is actually one of the most forgiving services in this respect. If your server is offline, the sending server will retry several times over 24-48 hours before it gives up. Even the big cloud email providers will do this.
That said, there are other aspects of running an email server that require some extra rigour, but they’re more on the sending side (making sure emails you send to other people actually land in their inbox). Doable, but one of the more challenging things to self-host.
What’s the resource usage like? I’ve looked into mailcow before but the recommended system specs are too expensive to make it worth it on a VPS.
Seems really low. I run it on a docker LXC with Nextcloud and bunch of other stuff, on 8 cores of an ancient dual Xeon Dell. I never seem to have to deal with latency on it.
mox. just one go binay. pure bliss: https://www.xmox.nl/
Oh this is one to watch! Thanks for posting. I’m currently running docker-mailserver (which is quite mature and stable) but xmox looks very interesting.
This is so cool… Didn’t know about it… And also european… Will try it for sure
Stalwart
Written in rust, contains SMTP, IMAP, JMAP, Sieve, CalDAV, CardDAV, WebDAV. Has an admin web ui. Sane defaults, minimal foot guns. No zoo of containers needed.
I’ve been trying out Stalwart, and it seems to be working good, but it is having problems with IDN that seem to require some weird ways of fixing.
(more specifically, Stalwart recognizes the punycode and UTF8 versions of domains as separate, which is difficult for some clients like Gmail web to deal with)
Beware it’s very heavyweight. My dedicated oldish server with 8gb ram and spinning hdes couldn’t even handle one single domani and a few users…
Was 6 months ago, tough.
Wow, what a waste!
I had to play with database types, because apparently out of the box setup works only on SSDs (??) And do a bunch of other stuff to improve performance.
End result was way worse than installing postfix+dovecot+dkim/dmark/etc stuff directly.
Quite unusable, but the hardware was limited
True. The default rocksdb is completely unusable on HDDs. For me it runs pretty good with PostgreSQL. Dovecot was certainly easier to handle with its file based storage and was super fast. But Postfix was a pain and I can’t count how often it bit me over the years (and since it’s SMTP, that means something broke in receiving, delivery or was suddenly a spam vector, which all sucks quite hard).
Rocksdb has tuning options for hard drives, but not sure Stalwart exposed them
I’ve had a good experience with mailcow. It’s not the most lightweight tho, and spins up quite a few containers.
+1 for mailcow, i’ve been running my mailserver for over 2 years now, very efficient, no hassle setup.
This is what I use as well and it’s pretty painless after setup.
You’re gonna have a bad time if you have to email MSFT/GOOG. MSFT was worse in my experience. their DumbScreen tech was horrible. Even the tech couldn’t get my emails to not go to spam. Gave up in the end. The likes of MSFT and Google make it nigh on impossible for people to self host their own email.
So I’ve been setting up Stalwart (but I probably won’t be using it), and I only had to unflag my emails as spam on Gmail and Outlook once; it even was able to send straight to the inbox of another Gmail account! I did have one email get quarantined by Outlook, but it was probably because the email and sender name didn’t match enough.
Been running my own mailserve for last 20 years and never had big issues.
Do dkim dmark stuff and DNS records properly and you will be fine. Also don’t spam and beware of spam-related subnets, and you should not have issues.
Have you considered that the reason why your mail server is trusted is because it’s been around for 20 years?
Have you tried to set up mail from scratch on a new domain/ip recently?
To be honest it’s mostly FUD. Self host email is perfectly doable provided that:
- you don’t use your home IP
- you do DNS records correctly
- you do DKIM & DMARC correctly
- you don’t send spam
What happened to me over the years was having the subnet my ip was is being associated to spammers, and that was a problem. It took several iterations with blacklists and my provider to get it sorted. That’s why I recommend using a reputable service provider that take care of spammers in a timely manner.
I’ve been running my own email server for 15+ years. One year ago I needed to change VPS providers and thus get a totally different IP. I worried about this a bit, but actually had no issues whatsoever. Of course, I wasn’t starting completely from scratch as I had the same domain, all my personal experience, and a battle-tested configuration for docker-mailserver. But yeah, the lack of IP reputation itself didn’t seem to be an issue at all. Maybe I got lucky. Or maybe it’s because I chose a relatively small Canadian VPS provider rather than one of the global cloud giants (I assume their IP address space gets pretty trashed with scammers).
What about domain reputation?
Yes, I migrated IP (from one provided to another) last year, and I recently added a new domain as well.
The new domain on the new ip just works, and the old domain on the same new ip just keep working.
Both the old and new ip are not residential IPs, I rent a small dedicated server for this purpose on the major hoster of my country. I pay about 15€/month for that, but it’s not only used for email, for all my services.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I’ve seen in this thread:
Fewer Letters More Letters DNS Domain Name Service/System IMAP Internet Message Access Protocol for email IP Internet Protocol LXC Linux Containers SMTP Simple Mail Transfer Protocol SSD Solid State Drive mass storage VPS Virtual Private Server (opposed to shared hosting)
7 acronyms in this thread; the most compressed thread commented on today has 15 acronyms.
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Have a look at https://mailu.io/ and https://docs.mailcow.email/
I’m still looking for a good solution that includes support for notes. I’m migrating off Exchange Online and using mailcow temporarily but the built in notes feature is sorely missed.
I use mailu, find it quite lightweight as well.
