Hey! I have been using Ansible to deploy Dockers for a few services on my Raspberry Pi for a while now and it’s working great, but I want to learn MOAR and I need help…

Recently, I’ve been considering migrating to bare metal K3S for a few reasons:

  • To learn and actually practice K8S.
  • To have redundancy and to try HA.
  • My RPi are all already running on MicroOS, so it kind of make sense to me to try other SUSE stuff (?)
  • Maybe eventually being able to manage my two separated servers locations with a neat k3s + Tailscale setup!

Here is my problem: I don’t understand how things are supposed to be done. All the examples I find feel wrong. More specifically:

  • Am I really supposed to have a collection of small yaml files for everything, that I use with kubectl apply -f ?? It feels wrong and way too “by hand”! Is there a more scripted way to do it? Should I stay with everything in Ansible ??
  • I see little to no example on how to deploy the service containers I want (pihole, navidrome, etc.) to a cluster, unlike docker-compose examples that can be found everywhere. Am I looking for the wrong thing?
  • Even official doc seems broken. Am I really supposed to run many helm commands (some of them how just fails) and try and get ssl certs just to have Rancher and its dashboard ?!

I feel that having a K3S + Traefik + Longhorn + Rancher on MicroOS should be straightforward, but it’s really not.

It’s very much a noob question, but I really want to understand what I am doing wrong. I’m really looking for advice and especially configuration examples that I could try to copy, use and modify!

Thanks in advance,

Cheers!

  • testgoofy@infosec.pubEnglish
    3·
    1 day ago

    Hey there,

    I made a similar journey a few years ago. But I only have one home server and do not run my services in high availability (HA). As @non_burglar@lemmy.world mentioned, to run a service in HA, you need more than “just scaling up”. You need to exactly know what talks when to whom. For example, database entries or file writes will be difficult when scaling up a service not ready for HA.

    Here are my solutions for your challenges:

    • No, you are not supposed to run kubectl apply -f for each file. I would strongly recommend helm. Then you just have to run helm install per service. If you want to write each service by yourself, you will end up with multiple .yaml files. I do it this way. Normally, you create one repository per service, which holds all YAML files. Alternatively, you could use a predefined Helm Chart and just customize the settings. This is comparable to DockerHub.
    • If you want to deploy to a cluster, you just have to deploy to one server. If in your .yaml configuration multiple replicas are defined, k8s will automatically balance these replicas on multiple servers and split the entire load on all servers in the same cluster. If you just look for configuration examples, look into Helm Charts. Often service provide examples only for Docker (and Docker Compose) and not for K8s.
    • As I see it, you only have to run a single line of install script on your first server and afterward join the cluster with the second server. Then you have k3s deployed. Traefik will be installed alongside k3s. If you want to access the dashboard of Traefik and install rancher and longhorn, yes, you will have to run multiple installations. Since you already have experience with Ansible, I suggest putting everything for the “base installation” into one playbook and then executing this playbook one.

    Changelog:

    • Removeing k3s install command. If you want to use it, look it up on the official website. Do not copy paste the command from a random user on lemmy ;) Thanks to @atzanteol@sh.itjust.works for bringing up this topic.
    • atzanteol@sh.itjust.worksEnglish
      4·
      1 day ago

      curl -sfL https://get.k3s.io/ | sh -

      Never, ever install anything this way. The trend of “just run this shell script off the internet” is a menace. You don’t know what that script does, what repositories it may add, what it may install, whether somebody is typo-squatting the URL and you’re running something else, etc.

      It’s just a bad idea. If you disagree then I have one question - how would you uninstall k3s after you ran that blackbox?

      • testgoofy@infosec.pubEnglish
        2·
        1 day ago

        Yes, just running a random script from the internet is a very bad idea. You should also not copy and paste the command from above, since I’m only a random lemmy user. Nevertheless, if you trust k3s, and they promote this command on the official website (make sure it’s the official one) you can use it. As you want to install k3s, I’m going to assume you trust k3s.

        If you want to review the script, go for it. And you should, I agree. I for myself reviewed (or at least looked over it) when I used the script for myself.

        For the uninstallment: just follow the instructions on the official website and run /usr/local/bin/k3s-uninstall.sh source

        • atzanteol@sh.itjust.worksEnglish
          3·
          1 day ago

          I really want to push back on the entire idea that it’s okay to distribute software via a curl | sh command. It’s a bad practice. I shouldn’t be reading 100’s of lines of shell script to see what sort of malarkey your installer is going to do to my system. This application creates an uninstall script. Neat. Many don’t.

          Of the myriad ways to distribute Linux software (deb, rpm, snap, flatpak, AppImage) an unstructured shell script is by far the worst.

          • moonpiedumplings@programming.devEnglish
            1·
            1 day ago

            I think that distributing general software via curl | sh is pretty bad for all the reasons that curl sh is bad and frustrating.

            But I do make an exception for “platforms” and package managers. The question I ask myself is: “Does this software enable me to install more software from a variety of programming languages?”

            If the answer to that question is yes, which is is for k3s, then I think it’s an acceptable exception. curl | sh is okay for bootstrapping things like Nix on non Nix systems, because then you get a package manager to install various versions of tools that would normally try to get you to install themselves with curl | bash but then you can use Nix instead.

            K3s is pretty similar, because Kubernetes is a whole platform, with it’s own package manager (helm), and applications you can install. It’s especially difficult to get the latest versions of Kubernetes on stable release distros, as they don’t package it at all, so getting it from the developers is kinda the only way to get it installed.

            Relevant discussion on another thread: https://programming.dev/post/33626778/18025432

            One of my frustrations that I express in the linked discussion is that it’s “developers” who are making bash scripts to install. But k3s is not just developers, it’s made by Suse who has their own distro, OpenSuse, using OpenSuse tooling. It’s “packagers” making k3s and it’s install script, and that’s another reason why I find it more acceptable.

            • atzanteol@sh.itjust.worksEnglish
              1·
              18 hours ago

              Microk8s manages to install with a snap. I know that snap is “of the devil” around these parts but it’s still better than a custom bash script.

              Custom bash scripts will always be worse than any alternative.

              • moonpiedumplings@programming.devEnglish
                1·
                18 hours ago

                I’ve tried snap, juju, and Canonical’s suite. They were uniquely frustrating and I’m not interested in interacting with them again.

                The future of installing system components like k3s on generic distros is probably systemd sysexts, which are extension images that can be overlayed onto a base system. It’s designed for immutable distros, but it can be used on any standard enough distro.

                There is a k3s sysext, but it’s still in the “bakery”. Plus sysext isn’t in stable release distros anyways.

                Until it’s out and stable, I’ll stick to the one time bash script to install Suse k3s.

                • atzanteol@sh.itjust.worksEnglish
                  1·
                  17 hours ago

                  You’re welcome to make whatever bad decisions you like. I can manage snaps with standard tooling. I can install, update, remove them with simple ansible scripts in a standard way.

                  Bash installers are bad. End of.

                  • moonpiedumplings@programming.devEnglish
                    1·
                    17 hours ago

                    Canonical’s snap use a proprietary backend, and comes at a risk of vendor lock in to their ecosystem.

                    The bash installer is fully open source.

                    You can make the bad decision of locking yourself into a closed ecosystem, but many sensible people recognize that snap is “of the devil” for a good reason.