Introduction to Kubernetes (k8) – a quick lookback | Hacker News Reader

Introduction to Kubernetes (k8) – a quick lookback

devopsprojectshq.com

33 pointsthomster23 comments

Would you trust a post that can't even get the abbreviation correct?

k8s has a meaning: in k-ubernete-s there are 8 letters between the k and the s.

For some reason many people don’t get such abbreviations: I’ve created an internal library ‘i8r = imagesaver’, explained this abbreviation everywhere, and some 5 years later, as we are transitioning off of it, about 10% of users don’t call it i-eight-r.

i8r doesn't work because it isn't pronounceable like k8s is

Do people actually use k8s as k-eight-s / "kates"?

I always use that pronunciation mentally myself but never heard anyone else use it.

I personally just always use kubernetes, or just my clusters...

oops, I literally forgot to add it, thanks for the heads up, I'll change it!

The linked presentation also consistently uses "k8"

Am I missing something? There seems to be very little substance here: No link to the presentation itself, only slides that lay a very ordinary introduction. Mentioning GitHub stars may have been the first red flag

Hi mate, the link is there in the blog text, just before the summary part.

There is a link to the presentation but yeah, there's not much substance in it either, a lot of nuance is skipped over, to the point where I'd consider it just wrong in places.

Some examples:

"Service object - Grouping object that gives you a stable IP (virtual IP) for the pods that have a certain LABEL": yes, you can use a Service to give your service a "stable IP", but that's just one type of Service; and yes, you can use a Service to target pods with a certain label, but selectors can do more than just that. (Also, what is a "virtual IP"?)

"Containers (Docker)" containers != docker

"Containers in a pod share the same IP address (localhost) and port space" this bit has been cribbed from "Kubernetes in action" (chapter 3 "Understanding how containers share the same IP and port space ": "they share the same IP address and port space") but for some reason they've inserted the "(localhost)" bit which is incorrect.

You can probably find better introductions on YouTube. The k8s docs are also quite understandable in themselves.

fair enough, but nothing actually clicked for me personally until I got my hands dirty, and actually used it....then all the components made sense......I tried to give a sense of it in the presentation....

Kubernetes is weird and unique software. I feel for it to be more like underlying layer, rather than end solution yet I end up using it as a solution, because all layers just add complexity.

At the same time its popularity makes it obvious that competition basically will not exist in the foreseeable future.

I'm not sure that I qualified to judge it, but I feel that Kubernetes has great architecture.

I was astounded when I realized that Kubernetes is super flexible when it comes to its underlying data model and API. At some time I wanted to reimplement it as a data store and I still think that it might make sense. Think about PostgREST but much more mature and flexible. Like you submit CRD which is JSON schema and then you can insert your entities, query them, listen for changes and so on. And organize your application as a set of "controllers" reconciling those entities into some final form. I just didn't see that kind of universal and flexible and successful architectures before. I assume that it exists in some internal projects.

Kubernetes has strictly defined scope and even reduces that over time. It does not do anything with containers or images, it delegates it to CRI plugin with several popular implementations (containerd and crio). It does not do anything with networking, it delegates it to CNI plugin with multiple popular implementations (flannel, calico, cilium just to name a few). It does not do anything to interact with cloud platforms like AWS, etc. It has some conventions about cloud controllers and cloud vendors implement those controllers, providing integration, scaling and other cloud-specific features.

At the same time I'm using Kubernetes "directly". I don't write stuff which generates yamls. I write yamls directly. Sometimes I use templating engines, mostly kustomize, but those do not reduce much work. And deploying simple application requires quite a lot of YAML lines, most of those being boilerplate. For example docker-compose provides super-concise language. I don't need to write any boilerplate, I just write stuff that makes sense. With Kubernetes, I sometimes have a feeling like I'm writing an assembly code instead of compact high-level code.

I feel like Kubernetes was supposed to be used with some great templating, but all we got was helm and kustomize...

It's not a huge issue, but that's probably a main issue for me.

Other than that, I pretty much like Kubernetes and would use it everywhere for production. Even for single server. It has some learning curve, but once I learned it, I like it and wouldn't use, say, docker instead. And I used a lot of docker.

> At the same time its popularity makes it obvious that competition basically will not exist in the foreseeable future.

That'd be a bummer.

To me, Docker Swarm feels like the logical next step after single node Docker Compose deployments - supports networking and multiple nodes, while still using the simple Compose syntax. Sure, it's not as all encompassing as Kubernetes, but it feels like sometimes the latter isn't worth its complexity (if you want to self-host everything), outside of options like K3s.

I'd even say that something like Hashicorp Nomad is pretty nice if you don't have a problem with HCL. Plus, it supports not just containers, which is probably a boon to many: https://developer.hashicorp.com/nomad/docs/drivers

Whatever happened to swarm? I tried it maybe once, and that's that. Can't remember the last time I've seen docker swarm in a job ad also? Pretty much everything revolves with kubernetes or some combination with nomad.

It is supported and probably works, but everyone just uses Kubernetes. If you're big, you want to use managed proven solution. If you're small, you expect to get big one day, and you want to use future-proof technologies to avoid unnecessary migrations. I think that's the way it works.

Hashicorp was bought by IBM, so I don't have high hopes for Nomad, either... IBM is a graveyard of good technologies.

oh man, just read it, too bad.....

I still use Docker Swarm and have seen it a few times, but yes, it’s definitely not common, which is a shame, because it also works pretty well with Portainer. Literally one of the most painless solutions run self-host and administer in my experience, at least for smaller scales.

I know that Docker like the company recently made a comeback (they had some financial issues), but never used Portainer, but they look cool...they remind me of Rancher....do they have a free version?

Yes, I’m using the Portainer community version myself, it also works with K8s so can serve as a lightweight alternative to Rancher as well, except last I checked there was a little bit of weirdness around non standard ingress controllers like Traefik instead of Nginx.

me too, that's kind of my point, once you get a feel for it, and understand it, you're set.

anyone else waiting for the popularity of k8s to shift to something else?

Why? K8s so far had been very well designed piece of mature and battle tested infra software and documentation is awesome. It also removed a lot of headaches over other proprietary junk I had to deal with. While many hopes and dreams are that docker compose or docker swarm would be enough, once your application group ranges above 100 and want less pampering, k8s is unbeatable.

so it's been like 10 years now, and I don't see it going anywhere....just look at rails, 20 years going and it's still widely used.....

Reply on news.ycombinator.com