Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Why is Kubernetes getting so popular?

stackoverflow.blog

Post reply on HN
Print view View original

71–80 of 681 posts

Re: Why is Kubernetes getting so popular?

#71

Post by UweSchmidt »

silviogutierrez wrote: post #4

For me, and many others: infrastructure as code. Kubernetes is very complex and took a long time to learn properly. And there have been fires among the way. I plan to write extensively on my blog about it. But at the end of the day: having my entire application stack as YAML files, fully reproducible [1] is invaluable. Even cron jobs. Note: I don't use micro services, service meshes, or any fancy stuff. Just a plain…

With "Swarm", do you mean Docker Swarm? Why has it "fizzled"?

The way I learned it in Bret Fisher's Udemy course, Swarm is very much relevant, and will be supported indefinitely. It seems to be a much simpler version of Kubernetes. It has both composition in YAML files (i.e. all your containers together) and the distribution over nodes. What else do you need before you hit corporation-scale requirements?

Re: Why is Kubernetes getting so popular?

#72

Post by fastball »

james-mcelwain wrote: post #60
bcrosby95 wrote: post #44

Earlier quoted context omitted.

I've only ever used cfengine and Ansible, but they are both declarative. Hell, Ansible uses yaml files too. I would be somewhat surprised to find out Puppet and Chef weren't declarative either. Because setting up a system in an imperative fashion is ripe for trouble. You may as well use bash scripts at that point. I've used Ansible for close to 10 years for hobby projects. And setting up my development environment. G…

Even though Ansible is declarative in spirit, in practice I feel like a lot of playbooks just read like imperative code.

I use Ansible for managing my infra, and the only time my playbooks look imperative is when I execute a shell script or similar, which is about 5% of total commands in my playbooks.

Re: Why is Kubernetes getting so popular?

#74

Post by fastball »

geofft wrote: post #65
bcrosby95 wrote: post #44

Earlier quoted context omitted.

I've only ever used cfengine and Ansible, but they are both declarative. Hell, Ansible uses yaml files too. I would be somewhat surprised to find out Puppet and Chef weren't declarative either. Because setting up a system in an imperative fashion is ripe for trouble. You may as well use bash scripts at that point. I've used Ansible for close to 10 years for hobby projects. And setting up my development environment. G…

Ansible is YAML, but it's definitely imperative YAML - each YAML file is a list of steps to execute. It uses YAML kind of like how Lisp uses S-expressions, as a nice data structure for people to write code in, but it's still code. Sure, the steps are things like "if X hasn't been done yet, do it." That means it's idempotent imperative code. It doesn't mean it's declarative. CFEngine is slightly less imperative, but w…

How does K8s know what order to do things in if there aren't steps? Because on a system, certain things obviously need to happen before other things.

Re: Why is Kubernetes getting so popular?

#75

Post by McAtNite »

silviogutierrez wrote: post #4

For me, and many others: infrastructure as code. Kubernetes is very complex and took a long time to learn properly. And there have been fires among the way. I plan to write extensively on my blog about it. But at the end of the day: having my entire application stack as YAML files, fully reproducible [1] is invaluable. Even cron jobs. Note: I don't use micro services, service meshes, or any fancy stuff. Just a plain…

Out of curiosity why do you feel swarm fizzled out?

I’ve deployed swarm in a home lab and found it really simple to work with, and enjoyable to use. I haven’t tried k8, but I often see view points like yours stating that k8 is vastly superior.

Re: Why is Kubernetes getting so popular?

#76

Post by heipei »

verdverm wrote: post #54
heipei wrote: post #50

My question is: Why is only k8s so popular when there are better alternatives for a large swath of users? I believe the answer is "Manufactured Hype". k8s is from a purely architectural standpoint the way to go, even for smaller setups, but the concrete project is still complex enough that it requires dozens of different setup tools and will keep hordes of consultants as well as many hosted solutions from Google/AWS/…

What are these alternatives with more users? Where is the momentum? Hosted GKE costs the same per month as an hour of DevOps time, what's wrong with paid management for k8s?

I didn't say more users, I said appropriate for more users. The alternative I mentioned is Nomad and I wish more people would give it a try and decide for themselves. The momentum behind it is Hashicorp, makers of Vault, Consul, Terraform, Vagrant, all battle-proven tools. The fact that there's one big player behind it really shows in how polished the tool, UI and documentation is.

The issue that I have with managed k8s is that these products will decrease the pressure to improve k8s documentation, tooling and setup itself. And then there's folks (like me) who want or need to run something like k8s on bare metal hardware outside of a cloud where the cloud-managed solution isn't available.

Re: Why is Kubernetes getting so popular?

#77

Post by cure »

pvorb wrote: post #56
silviogutierrez wrote: post #20

Earlier quoted context omitted.

So terraform is a higher-order, meta-Kubernetes. It's very rarely used, but who provisions the cluster itself? That's terraform. So terraform creates the cluster, DNS and VPC. Then k8s runs pretty much everything.

Why would you want to provision your own k8s cluster, if you can use EKS, AKS or similar?

EKS, GKE and the like have a number of limitations. For example: they can be pretty far behind in the version of K8S they support (GKE is at 1.15 currently, EKS at 1.16; K8S 1.18 was released in at the end of March this year.

Re: Why is Kubernetes getting so popular?

#78

Post by geofft »

silviogutierrez wrote: post #37
bosswipe wrote: post #31

Earlier quoted context omitted.

According to the article you are wrong about "infrastructure as code". Kubernetes is infrastructure as data, specifically YAML files. Puppet and Chef are infrastructure as code. Edit: not sure why the down votes, I was just trying to point out what seems like a big distinction that the article is trying to make.

Maybe? I'm too lazy to formally verify if the YAML files k8s accepts are Turing complete. With kustomize they might very well be. How about "infrastructure-as-some-sort-of-text-file-versioned-in-my-repository". It's a mouthful, but maybe it'll catch on.

They don't do loops or recursion. They don't even do iterative steps in the way that Ansible YAML has plays/tasks.

Yes, higher-level tools like Kustomize or Jsonnet or whatever else you use for templating the files are Turing-complete - but that's at the level of you on your machine generating input to Kubernetes, not at the level of Kubernetes itself. That's a valuable distinction - it means you can't have a Kubernetes manifest get halfway through and fail the way that you can have an Ansible playbook get halfway through and fail; there's no "halfway." If something fails halfway through your Jsonnet, it fails in template expansion without actually doing anything to your infrastructure.

(You can, of course, have it run out of resources or hit quota issues partway through deploying some manifest, but there's no ordering constraint - it won't refuse to run the "rest" of the "steps" because an "earlier step" failed, there's no such thing. You can address the issue, and Kubernetes will resume trying to shape reality to match your manifest just as if some hardware failed at runtime and you were recovering, or whatever.)

Re: Why is Kubernetes getting so popular?

#79

Post by mancini0 »

Lets use Bazel, and Bazel's rules_k8s to build\containerize\test\deploy only the microservices of my monorepo that changed.

Lets use Istio's "istioctl manifest apply" to deploy a service mesh to my cluster that allows me to pull auth logic / service discovery / load balancing / tracing out of my code and let Istio handle this.

Lets configure my app's infrastructure (Kafka (Strimzi), Yugabyte/Cockroach, etc) as yaml files. Being able to describe my kafka config (foo topic has 3 partitions, etc) in yaml is priceless.

Lets move my entire application and its infrastructure to another cloud provider by running a single bazel command.

k8s is the common denominator that makes all this possible.

Re: Why is Kubernetes getting so popular?

#80

Post by twblalock »

gatvol wrote: post #39

K8s is great - if you are solving infrastructure at a certain scale. That scale being a Bank, Insurance Company or mature digital company. If you're not in that class then it's largely overkill/overcomplex IMO when you can simply use Terraform plus managed Docker host like ECS and attach cloud-native managed services. Again the cross cloud portability is a non starter, unless you're really at scale.

> you can simply use Terraform plus managed Docker host like ECS and attach cloud-native managed services

That's not actually simple at all, and you would need to build a lot of the other stuff that Kubernetes gives you for free.

Kubernetes gives you an industry standard platform with first-class cloud vendor support. If you roll your own solution with ECS, what you are really doing is making a crappy in-house Kubernetes.

Post reply on HN