Kubernetes Pod commands and manifest file

To Create the pod ( with name nginx-pod by using nginx docker image)  with command

    kubectl run nginx-pod --image nginx

To list the pod with its IP address and NodeName

    kubectl get pods -o wide

To interact with pod's terminal(go inside the pod)

    kubectl exec -it nginx-pod-- bash

To Exit from the pod run "exit" command

To access the application running in the pod ( consider 192.168.135.2 is IP of the pod)

     curl 192.168.135.2

To find all the properties of the pod in yaml format

    kubectl get pods nginx-pod -o yaml

To find all the properties of the pod in json format

    kubectl get pods nginx-pod-o json

To Delete the Pod

    kubectl delete pod nginx-pod

Manifest file in Kubernetes 

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Kubernetes Documentation

My First Pod Manifest file (nginx-pod.yaml)

apiVersion: v1 # apiVersion for the resource

kind: Pod  # type of resource (Pod)

metadata:

  name: myapp # Pod name

  labels:  # user defined key value pair

    name: myapp # name is the key and myapp is value

spec:

  containers: # Containers information for the pod

  - name: myapp # name of the container to access via pod

    image: nginx # docker image for myapp container

    # below code is optional

    resources: # resources define the memory or cpu limits for a container

      limits:  # maximum limit for the container

        memory: "128Mi"  # maximum 128 mb of memory used by the container

        cpu: "500m"  # maximum cpu usage 500mz

    ports: # Ports where the container's app is running

      - containerPort: 80 # nginx runs on port 80

To create Pod by using above file you need to run below command

            kubectl create -f nginx-pod.yaml

To Verify Pod is created with its IP address and other properties

             kubectl get pods -o wide

To Verify the events and other run-time properties of the pod.

          kubectl describe pod myapp

If you make any change in the manifest file then use the  apply(change/create) command

          kubectl apply -f nginx-pod.yaml

To find the logs generated by pod

         kubectl logs myapp

To interact with pod

         kubectl exec -it myapp -- bash

To delete the pod using manifest file

          kubectl delete -f nginx-pod.yaml

To verify pod is deleted or not

        kubectl get pods

MultiContainer Pod

Create 2 containers (nginx, tomcat) within a single pod multicont.yaml

apiVersion: v1

kind: Pod

metadata:

  name: myapp

  labels:  

    name: myapp

spec:

  containers:

  - name: nginx-container

    image: nginx

     # below code is optional

    resources:

      limits:  

        memory: "64Mi"  

        cpu: "100m"  

    ports:

      - containerPort: 80 # nginx runs on port 80

  - name: tomcat-container

    image: tomcat  

    # below code is optional

    resources:

      limits:  

        memory: "64Mi"  

        cpu: "200m"  

    ports:

      - containerPort: 8080 # tomcat runs on port 8080

To create Pod by using above file you need to run below command

            kubectl create -f multicont.yaml

To Verify Pod is created with its IP address and other properties

             kubectl get pods -o wide

To Verify the events and other run-time properties of the pod.

          kubectl describe pod myapp

If you make any change in the manifest file then use the  apply(change/create) command

          kubectl apply -f multicont.yaml

To find the logs generated by pod nginx-container

        kubectl logs myapp -c nginx-container

To find the logs generated by pod nginx-container

        kubectl logs myapp -c tomcat-container

To interact with pod for nginx-container

    kubectl exec -it myapp -c nginx-container -- bash

To interact with pod for tomcat-container

    kubectl exec -it myapp -c tomcat-container -- bash

To access nginx app using multicontainer pod (IP 192.168.135.3)

    curl 192.168.135.3:80

To access tomcat app using multicontainer pod (IP 192.168.135.3)

    curl 192.168.135.3:8080

To delete the pod using manifest file

          kubectl delete -f multicont.yaml

To verify pod is deleted or not

        kubectl get pods