Kubernetes – Pod
It’s possible to create pods with multiple containers inside them. For example, keeping a database container and a data container together in a pod.
Types of Pod
Pods come in two types:
- Single container pod
- Multi container pod
Single Container Pod
Kubectl run can be used to create pods, where we specify an image on the Docker registry which we will pull when creating the pod.
$ kubectl run <name of pod> --image=<name of the image from registry>Example − Let’s create a pod with a Tomcat image from Docker Hub.
$ kubectl run tomcat --image = tomcat:8.0Alternatively, you can create the yaml file and then run kubectl create.
apiVersion: v1 kind: Pod metadata: name: Tomcat spec: containers: - name: Tomcat image: tomcat: 8.0 ports: containerPort: 7500 imagePullPolicy: Always
As soon as the above yaml file is created, we’ll save it as tomcat.yml and run the create command.
$ kubectl create –f tomcat.ymlTo describe the pod, use the describe command along with kubectl.
Multi Container Pod
A multi-container pod is created using yaml mail with the container definitions.
apiVersion: v1 kind: Pod metadata: name: Tomcat spec: containers: - name: Tomcat image: tomcat: 8.0 ports: containerPort: 7500 imagePullPolicy: Always -name: Database Image: mongoDB Ports: containerPort: 7501 imagePullPolicy: Always
We’ve created one pod with two containers, one for Tomcat and one for MongoDB, in the above code.
