I’m a retired Unix admin. It was my job from the early '90s until the mid '10s. I’ve kept somewhat current ever since by running various machines at home. So far I’ve managed to avoid using Docker at home even though I have a decent understanding of how it works - I stopped being a sysadmin in the mid '10s, I still worked for a technology company and did plenty of “interesting” reading and training.
It seems that more and more stuff that I want to run at home is being delivered as Docker-first and I have to really go out of my way to find a non-Docker install.
I’m thinking it’s no longer a fad and I should invest some time getting comfortable with it?
Docker is nice for things that have complex installations and I want a very specific implementation that I don’t plan to tweak very much. Otherwise, it’s more hassle than it’s worth. There are lots of networking issues like limited/experimental support for IPv6, and too much is hidden and preconfigured, making it difficult to make adjustments that would otherwise just be a config file change.
So it is good for products like a mail server where you want to use the exact software they use like let’s say postfix + dovecot + roundcube + nginix + acme + MySQL + spam assassin + amavisd, etc. But you want to use an existing reverse proxy and cert it setup, or want to use a different spam filter or database and it becomes a huge hassle.
Can you recommend a mail server docker image like that? I have a hand cranked iredmail server that I’ve been babying for 5 years but I want to move it to either docker or an LXC.
I use Mailcow and like it a lot.
I use a mail service (MXRoute) as an outbound SMTP relay though, since I don’t want to have to deal with deliverability, especially to picky services like Microsoft Hotmail/Outlook. It’s a trade off. Other relays like SMTP2Go and Amazon SES work well too.
So I’m self-hosting the mailboxes, but when I send mail through my server, it sends them via MXRoute.
https://github.com/docker-mailserver/docker-mailserver
Mailcow or Mailu have pretty good setups if you don’t want to do anything too different and don’t need to keep resource usage to a minimum.
I haven’t had any issues with IPv6. If you want to, you can just use a macvlan network and rely on SLAAC. I manually assigned ULA addresses to some containers and it’s working well.
Also as a side note, it’s not common for mail servers to use SpamAssassin any more. Most have moved to rspamd which is more powerful and much more efficient.