Kubernetes Interview Questions

Q1: Docker Vs Kubernetes

Ans: Docker is a container platform whereas kubernetes is a container orchestration platform that offers features such as auto healing , scaling and enterprice level support like load balancing.

Q2: What are the main components of k8s architecture ?

Ans:

1. Control Plane : Api server , Scheduler , Etcd , Controller manager, Cloud controller manager

2. Dataplane: Kube proxy , Container runtime , Kubelet.

Q3: Docker container vs pod

Ans: Containers are like a box which has application , dependencies running inside it whereas pod is also the same thing but in pod we write specification in yaml file and we can run more than one conatiner inside one pod.

Q4: What is k8s namespace

Ans: Its is a logical isolation of resources so we can run multiple projects inside same cluster and one project will not interfere work of another.

Q5: What is the role of kube proxy

Ans: It is the essential component of kuberenets cluster , present in dataplane, and ensures that services can communicate with each other. For ex: When client sends request to the service it is intercepted by the kube-proxy on the node where it is received. kube-proxy then looks up for the destination endpoint for the service and routes accordingly.

Q6: What are the different type of services within kubernetes

Ans:

1. Cluster IP

   Only for the those having access to the cluster.

2. Node port

   Only for those having access to the worker nodes

3. Loadbalancing

   Helps to access cluster to the external world , it uses cloud controller manager which helps to connect the k8s cluster with cloud provider and provides the public IP like ELB in AWS which helps user to connect with the cluster and access it.

Q7: What is the role of kubelet ?

Ans: It helps in creation of the pod and make sure that pod is in running state. If pod goes down it informs to API server then API server informs to replicaset controller to spin up the new pod.