Kubernetes in 5 mins

[Music] hi my name is Pete Aguilar I'm a director of technical product management here at VMware in our cloud native apps business unit and this lightboard session is all about giving kubernetes to you in five minutes and it's going to be a little bit of a challenge so I'm going to have to brush over a lot of detailed concepts in kubernetes but I want to give you a rough idea of what is it and what does it actually do and what is it responsible for so there's a few different architectural components two of which I'm going to talk about the first of which is the kubernetes cluster services and you know the fundamental premise behind kubernetes is that we can enforce what's called desired state management and really what that means is that I'm going to feed the cluster services a specific configuration and it will be up to the cluster services to go out and run that configuration in my infrastructure okay one of the main components that I do want to call out is this API that sits in front of all this in the API services so that is one building block of the system the second building block of the system is this thing called a worker and what is a worker well a worker is really just a container host the one thing unique about a worker or the container host in a kubernetes environment is that it does have this cubelet process that runs which is responsible for communicating with yes you guessed it the kubernetes cluster services and so this whole thing the cluster services the workers themselves that's what makes up this quote/unquote kubernetes cluster so let's talk about the use case here so in this case what we want to do is we want to feed this the configuration so the desired state so to speak exist here in a deployment yeah file so here I'm just going to call it application one dot yeah Mille and inside this there can be a whole bunch of configuration information I am going to bypass quite a bit of it but I am going to talk about two fundamental pieces the first of which in this deployment file is a pod configuration in a pod is like the smallest unit of deployment in kubernetes in terms of the kubernetes object model and what it means is that in a pod I can have running containers and you can have one or more so in order to run that pod I need to specify some sort of container image maybe I want to have two container images and further down the line there's other things like what TCP port and where services running or whatnot but the other additional thing is that I'm going to specify how many of these pods need to be running here so maybe there's three for pod number one I can also list additional pod so here's pod leaves different color so pod number two and I basically have container image number three and then replicas off my configuration file equal to two so what happens I will take this deployment file I will feed it to the API and it will bit up it will be up to the cluster services to figure out how to schedule these pods in the environment and make sure that I have the right number of pods running so I feed this file over here let's work on pod one so I'm going to have pod one replica one pod one replica two pod one replicas three in addition I've also got my pod two so here we are pod two replica one and in this case we only have two replicas here so let's just do pod one replica two here and so you can see at any point in time the cluster services are responsible to make sure that configuration is running across all of my container or my workers so what is what's a unique scenario that happens here what happens if I lose a worker now my running configuration because that pot is now dead my running configuration does not match this and it's up to the kubernetes cluster services through the cubelet process that's running to notify me of that and to understand what's actually running so what I've done is I actually drop this pod one replica to so therefore the scheduler has to make a scheduling decision on where I need to instantiate that so it will just pick one of the workers whoops that will be pod one and in this case this is replica two so this is kind of the basics of kubernetes in five minutes hope you enjoyed it stay tuned for more light board sessions on the subject of kubernetes with photon platform thanks [Music] you [Music]

Channel: VMware Cloud Native Apps

Views: 1,788,706

Rating: 4.7193446 out of 5

Keywords: Cloud Native, Container Networking, Software Defined Networking, SDN, Cloud Computing, Virtual Infrastructure, Kubernetes, K8s, VMware, Cloud Architecture, Application Development, Tech, Tech 101, Cloud Technology

Id: PH-2FfFD2PU

Length: 5min 37sec (337 seconds)

Published: Mon May 15 2017

Reddit Comments

[u/vensoh]

That should be P2R2 right?

[u/JBlitzen]

Watched the whole thing, have absolutely no idea why I would use kubernetes, what it helps me do that other solutions don't, how to utilize it for that kind of purpose, or pretty much anything else about it. I'm okay with skipping some of that, but he skips all of it.

This is not an introduction to kubernetes, it's an introduction to kubernetes TERMINOLOGY.

THIS is a good intro to kubernetes: https://www.youtube.com/watch?v=1lgsQ3PKz9M

[u/RecycledGeek]

Am I the only one watching this thinking, "Wow, he writes backwards REALLY well!"?

[u/Gnapstar]

Would the Kubernetes Cluster Service tell you if the workers are overloaded and that you'd need more workers, or would you need additional tools for that? Never used/tried Kubernetes before, it seems pretty cool

[u/digitalpacman]

Did enjoy. The writing backwards thing freaks me out. But I like the format.

[u/pedro_cucaracha]

„Desired State Managemt“

[u/ClutchDude]

Good overview and quick primer for those who have passing familiarity with container orchestration.

As usual, the devil is in the details: Take for instance kubernetes networking - I don't think many folks could easily describe a holistic view of how the various networking components and plugins work together without it coming off as a confusing mess.

[u/TheZanke]

5 minutes? More like 3m20s AMIRITE?

[u/The_Speaker]

This could also apply to many cloud services. Concept would hold true. Bosh for example.