it's not always sunny with podman

I am moving from docker to podman and selinux because I thought that podman is more secure and hence, the future. I thought the transition will be somewhat seamless. I even prepaired containers but once I migrated I still ran into issues.

minor issue: it’s podman-compose instead of podman compose. The hyphen feels like a step back because we moved from docker-compose to docker compose. But thT’s not a real issue.

podman does not autostart containers after boot. You have to manually start them, or write a start script. Or create a systemd unit for each of them.

Spinning up fresh services works most of the time but using old services that worked great with docker are a pain. I am wasting minutes after minutes because I struggle with permissions and other weird issues.

podman can’t use lower number ports such that you have to map the ports outside of the machine and forward them properly.

Documentation and tutorials are “all” for docker. Github issues are “all” for docker. There isn’t a lot of information floating around.

I’m still not done and I really wonder why I should move forward and not go back to docker. Painful experience so far. linuxhandbook.com/docker-vs-podman/ and following pages helped me a lot to get rid of my frustration with podman.

starryoccultist,
@starryoccultist@lemmy.sdf.org avatar

minor issue: it’s podman-compose instead of podman compose. The hyphen feels like a step back because we moved from docker-compose to docker compose. But thT’s not a real issue.

podman does not autostart containers after boot. You have to manually start them, or write a start script. Or create a systemd unit for each of them.

I’m also currently migrating all of my self-hosted services from docker to podman. Look into using Quadlet and systemd rather than podman-compose: www.redhat.com/sysadmin/quadlet-podman

Your Quadlet .container files will end up looking very similar to your docker compose files. Podman will automatically generate a systemd service unit for you if you drop the .container file in your user systemd unit directory ($HOME/.config/containers/systemd/) and run systemctl --user daemon-reload. Then starting the container on boot is as simple as systemctl --user enable --now containername.service.

This will not solve your rootful vs. rootless issues, as others have pointed out, but Quadlet/systemd is nice replacement for the service/container management layer instead of docker-compose/podman-compose

tau,

+1 for quadlet. It’s another file format to learn, but it’s worth it, particularly if you want your containers to auto-update. Also check out podlet to help mitigate some of the compose to .container issues.

llii,

podman does not autostart containers after boot.

Does docker do this? I wrote a systemd unit for my docker container because I thought that there is no way for docker to autostart containers?

Molecular0079,

It does. You probably did not enable docker.service to start on boot.

llii,

Ok, i need to check this later. Thanks!

ikidd,
@ikidd@lemmy.world avatar

Not sure about straight docker run commands, but if you’re using docker compose you can add restart: unless-stopped or always to your docker-compose.yml to have it come up on boot.

mvirts,

You must have been expecting philadelphia

GunnarGrop,

Writing systemd services for your containers is something yoully have to get used to with podman, pretty much. It’s actually very easy with the built in command “podman generate systemd”, so you can just do something like " podman generate systemd --name my-container > /etc/systemd/system". I much prefer managing my containers with systemd over the docker daemon. It’s nice!

Also, podman can use privileged ports as root, right?

rsolva,
@rsolva@lemmy.world avatar

Podman is great, but a lot of confusion arise from the rapid development the last ~year and the fact that different distros have relatively old versions in their repos.

I recommend using the latest Fedora Server and defining your containers as quadlets. Also, on Fedora, yoi can install Cockpit (and cockpit-podman) and get a decent webgui to manage your host and container.

I should just write a blog post about this instead of typing this up on my phone in bed 😆

sunbeam60,

Yes please!!!

lemmyingly,

Why do you believe podman is more secure than root-less Docker? Please educate me.

I run root-ful and root-less Docker daemons at the same time on the same machine because there are limitations to what you can do without as root privileges. So where possible, containers run in root-less Docker and the lucky few that require root privileges run in root-ful Docker.

GravitySpoiled,

I can’t

nickwitha_k,

For the low-port issue, maybe try something like how K8S tends to handle it:

  • One container that is either rootful or allowed to use low ports. Run a reverse proxy like HAProxy or Envoy in this.
  • All other containers for services, run on high ports, pointing to them in the reverse proxy container’s config.
  • Don’t use bare http, unless required. Getting valid TLS certs is dead easy and free with LetsEncrypt.
  • All
  • Subscribed
  • Moderated
  • Favorites
  • •
  • linux@lemmy.ml
  • fightinggames
  • All magazines
    •