zlacker

>>jakels+(OP)
> I also enabled UFW (which I should have done ages ago)

I disrecommend UFW.

firewalld is a much better pick in current year and will not grow unmaintainable the way UFW rules can.

    firewall-cmd --persistent --set-default-zone=block
    firewall-cmd --persistent --zone=block --add-service=ssh
    firewall-cmd --persistent --zone=block --add-service=https
    firewall-cmd --persistent --zone=block --add-port=80/tcp
    firewall-cmd --reload

Configuration is backed by xml files in /etc/firewalld and /usr/lib/firewalld instead of the brittle pile of sticks that is the ufw rules files. Use the nftables backend unless you have your own reasons for needing legacy iptables.

Specifically for docker it is a very common gotcha that the container runtime can and will bypass firewall rules and open ports anyway. Depending on your configuration, those firewall rules in OP may not actually do anything to prevent docker from opening incoming ports.

Newer versions of firewalld gives an easy way to configure this via StrictForwardPorts=yes in /etc/firewalld/firewalld.conf.

>>3np+pm

  > Specifically for docker it is a very common gotcha that the container runtime can and will bypass firewall rules and open ports anyway. 

Like I said in another comment, drop Docker, install podman.

>>except+3q
I keep reading comments by podman fans asking to drop Docker and yet every time I have tried to use podman it failed on me miserably. IMHO it would be better if podman was not designed and sold as a docker drop in replacement but its own thing.

>>kh_hk+cm1
That sucks, I never had any problem running a Dockerfile in podman. I don't know what I do differently, but I would as a principle filter out any container that messes with stuff like docker in docker. Podman doesn't need these kind of shenegians.

Also the Docker Compose tool is a well-know exception to the compatibility story. (There is some unofficial podman compose tool, but that is not feature complete and quadlets are better anyway.)

I agree with approaching podman as its own thing though. Yes, you can build a Dockerfile, but buildah lets you build an efficient OCI image from scratch without needing root. For those interested, this document¹ explains how buildah compares to podman and docker.

1. https://github.com/containers/buildah/tree/main/docs/contain...

>>except+UA1
A side-effect of running rootless and daemonless is that containers stop on user log out, and I can't believe how all this is to be expected for a newcomer to parse. Because I thought the whole point of containers in production was for them to keep running when you log out.

Of course, when you think about it, nobody expects a command to just survive logging out, but coming from docker, you still have that expectation. And I wonder, am I supposed to be running this on a tmux like the old days? No, you need to do a bunch of systemd/linger/stuff. So being that we are already in systemd land, you keep searching and end up in quadlets, which are a new-ish thing with (last I checked) bad docs, replacing whatever was used before (which has good docs). Docs, being said, that give k8s ptsd. Quadlet, podlet and pods.

It seems that when podman deviates from docker, it does in the least ergonomic way possible. Or maybe I have been lobotomized by years and years of using docker, or maybe my patience threshold is very low nowadays. But this has been my experience. I felt very stupid when I deployed something and it stopped after 5 minutes. I was ready to use podman, because it worked locally. And then it failed in production. Thanks no.

>>kh_hk+kj3

  loginctl enable-linger

>>except+Ls3
Yes, but I want it to only apply to podman, not any running task.

    systemctl --user enable podman.socket loginctl enable-linger <USER>

?

>>kh_hk+dz3
You should compare it imho to ssh. If you break your connection, your session is gone. So if you only want certain parts of your session survive, which ones should? Because maybe your container depends on avahi on the host, or cups, or...?

Just a random thought, but if you can create a user on the host that just has the most minimal set of systemd services enabled your container needs, you could apply it to that user.

But still, on a server that wouldn't make much sense imho, as the default user is usually the service user having a minimal set of services enabled. On a desktop, your default user is logged in anyways. So I think this isn't a real problem tbh.