Kubernetes - basic hands-on

First, let’s get some basic understanding:

Kubernetes is an open-source container-orchestration system for automating computer application deployment, scaling, and management. It was originally designed by Google and is now maintained by the Cloud Native Computing Foundation.

Here the simple idea of words we are going to use,

containers : lightweight docker images running in(docker images are lightweight because it has no kernel)

lets say the container is down, that means there is no management for the service(if that docker container has a service), then that is why Kubernetes comes to the picture

Pod : we can have one or multiple containers in a pod. If the pod is running on a network and it is called pod network

Master : Who is managing the cluster

Worker nodes : where the actual containers are running

you will see the nodes in the Kubernetes cluster using following command:

kubectl get nodes

Let’s create a pod using a test.yml file, here a nginx docker image is going to be used

vi test.yaml

apiVersion: v1

kind: Pod

metadata:

name: nginx-pod

spec:

containers:

- name: c1

  image: nginx

after, execute the command to create the pod using kubectl command

kubectl create -f pod.yaml

To list the pods created, 

kubectl get pods

 if you need more detailed list , use following command

kubectl get pods -o wide

Then you will see the ip address and etc.

To see detailed information about a specific pod, use following command. Every pod can have a one container or multiple containers;

kubectl describe pod nginx-pod

Then you will get the details of the nginx pod you created in the terminal.

Let’s see how we can access this application

Accessing any pod which is in pod network using service is the best way.

To be continued....