Kubernetes Terminology every admins need to know | Learn Kubernetes – Part 4

There are many terminology you need to know if you are new to Kubernetes and going to setup a Kubernetes environment. To make it more simpler, I have listed down most of them here in this article.

Nodes:

  • Nodes are the hosts that run Kubernetes applications.

container-applications-pods-kubernetes1

  • A Node is a worker machine in Kubernetes and may be either a virtual or a physical machine, depending on the cluster.
  • Each node is manage by the Master.
  • A node can have multiple pods.
  • Kubernetes master automatically handles scheduling the pods across the nodes.

Containers:

  • Containers are the units of packaging for development, shipment and deployment.Tintri-containers-support-blog
  • Containers are a solution to the problem of how to get software to run reliably when moved from one computing environment to another.
  • Docker is a popular, open-source container format that is supported on Google Cloud Platform and by Google Kubernetes Engine.

Pods:

  • Pods are unit of deployment.

Kuberenetes Pods

  • It is basic building blocks in Kubernetes.
  • It is a group of containers that are deployed together on the same host.
  • It represents a single instance of a running process in your cluster.

Replication Controller:

  • It ensures availability and scalability.

Replication Controller

  • It ensures a given number of pods are running in the cluster at a given time.
  • You use it on regular basis to launch one or more instances of your applications.
  • Each replication controller has a desired state that is managed by the application deployer.
  • It is a structure that enables you to easily create multiple pods, then make sure that that number of pods always exists. If a pod does crash, the Replication Controller replaces it.
  • It is also known as ReplicaSet

Labels:

  • Labels are the Key-Value pairs for identification.

kubernetes label

  • When creating Kubernetes objects, one can give any number of labels to each object which are discoverable across the system.
  • It is kind of tagging the instances.
  • It use to organize Kubernetes objects.
  • It certain restrictions concerning length and allowed values

Services:

  • Services are collection of pods exposed as an endpoint.
  • It is a grouping of pods that are running on the cluster.

Kubernetes Services

  • It enables communication between various component of within and outside of applications.
  • It help us to connect applications with other applications.
  • You can have many services within the cluster.
  • It provides features such as load-balancing, service discovery between applications, and features to support zero-downtime application deployments.
  • Each service has a pod label query which defines the pods which will process data for the service.
  • Kubernetes services are an abstraction for pods, providing a stable, virtual IP (VIP) address.

Namespace:

  • Namespace is use for managing Kubernetes cluster.
  • It is helpful when multiple teams are using the same cluster and there is potential of name collision.
  • It helps communication between pods.
  • Namespace are the virtual cluster which is on top of physical cluster.
  • If you are a windows guy, it is similar to the concept of DFS namespace in Windows environment.

These all are the most comonly used terminology which you need to know before proceeding for the setup. If you have more concepts to add in this topic, please do share in comment box.

In next article, we are going to explore how to setup the Kubernetes environment.

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Related Articles: –

What is Kubernetes? | Learn Kubernetes – Part 1

Components and Architecture of Kubernetes | Learn Kubernetes – Part 2

Versions of Kubernetes | Learn Kubernetes – Part 3

Kubernetes Terminology every admins need to know | Learn Kubernetes – Part 4

Getting Start to Setup and Configure Kubernetes | Learn Kubernetes – Part 5

How to Install Kubernetes on Windows 10 with Hyper-v using Minikube| Learn Kubernetes – Part 6