Kubernetes Interview Questions PDF By ScholarHat

Kubernetes Interview Questions for Freshers and Advanced
Professionals
Kubernetes Interview Questions
Getting ready for a Kubernetes interview requires focus and a clear understanding of essential concepts. With proper
preparation, you can tackle the process with conﬁdence and excel in both technical and practical discussions. This
guide will walk you through key Kubernetes topics and questions to help you succeed. Let’s begin.
What to Expect in the Kubernetes Interview?
The Kubernetes interview process evaluates your ability to manage and orchestrate containerized applications. Here's
what you can expect:
Questions on core Kubernetes concepts, including Pods, Deployments, Services, and ConﬁgMaps.
Scenario-based tasks to assess skills in scaling, monitoring, and troubleshooting clusters.
Questions about setting up and managing Kubernetes in cloud environments.
Implementing networking solutions and ensuring high availability of clusters.
Understanding the integration of Kubernetes with CI/CD pipelines.
Familiarity with containerization tools like Docker.
In this Interview tutorial, we’ll explore Kubernetes interview questions and answers, the key stages of the interview process,
technical discussions, Kubernetes questions for freshers, advanced topics for experienced candidates, and tips to excel in
your interview.

Read More: Containers in Azure
This is the brain of the Kubernetes cluster. It coordinates all activities, such as:
Scheduling applications
Maintaining the state of applications
Scaling applications as needed
Rolling out updates
A Kubernetes cluster is a distributed system designed to manage containers in a flexible and scalable way. It focuses on
deploying, maintaining, and scaling workloads. The cluster works by resolving the state of the system, ensuring that the
actual state matches the desired state, which is known as self-healing.
The underlying hardware of the nodes is abstracted away, providing a uniform interface for workloads to access shared
resources. This makes deployment easier and more efficient.
Kubernetes is an open-source platform designed to manage containerized applications across clusters. It simplifies the
scheduling, execution, and scaling of these applications. At its core, Kubernetes relies on two main components:
These are the worker machines in the cluster. Each node is an instance of an operating system that runs the necessary
processes to execute containers. Nodes have two key components:
Kubelet: An agent that manages and communicates with the master.
Container Tools (like Docker): These are used for running container operations.
Kubernetes Cluster
What is Kubernetes?
Nodes
Master
Pods: The Smallest Deployable Unit

Even though a pod may contain multiple containers, they are always scheduled to run on the same node to ensure they can
share resources effectively.
In Kubernetes, Pods are the smallest deployable objects. They represent one or more containers that are deployed together
as a single unit.
A Pod always runs on a Node.
All containers inside a pod share:
Resources like storage volumes
A unique IP address within the cluster
Information on how to run each container
Kubernetes Services provides a uniﬁed way to access the workloads running within pods. Services abstract the complexity
of connecting to individual pods and ensure that users or other services can access the applications without worrying about
the underlying pods.
Services: Accessing Workloads
1. What is a Volume in Kubernetes?
Kubernetes Interview Questions and Answers For Freshers

Ans:Here’s how Kubernetes works at a high level:
Application Description: The application is described in a YAML file (also called a configuration or spec file).
Pod Deployment: Using this YAML file, Kubernetes deploys the application in the form of pods on a cluster or node.
Self-healing: Kubernetes ensures that the desired state is always met, making the system resilient and capable of
recovering from failures.
This flow helps streamline the deployment, scaling, and management of applications within Kubernetes clusters.With
Kubernetes, managing containers and orchestrating complex systems becomes much simpler and more efficient!
Ans: A Deployment provides declarative updates to Pods and ReplicaSets. It allows you to define the desired state for your
Pods, and Kubernetes will automatically manage the updates. If a Pod goes down or is deleted, the Deployment ensures that
a new one is created.
Example: If you want to update the version of an app, Kubernetes automatically rolls out the new version to your Pods.
Ans:A volume is a way to store data that can be shared between containers in a pod or persist data beyond its lifecycle.
Kubernetes supports several types of volumes like emptyDir, hostPath, NFS, persistentVolumeClaim, and more.
Ans: A Service is an abstraction that exposes a set of Pods as a network service. It enables communication between Pods,
whether they’re inside or outside the cluster, and allows you to access your application in a reliable manner, even if the
underlying Pods change.
For example, a LoadBalancer Service can be used to expose your application to external traffic.
2. Explain Kubernetes Workflow.
4. What is a Service in Kubernetes?
5. What is a ConfigMap in Kubernetes?
3. What is a Deployment in Kubernetes?

Aspect
Definition
Components
Pod A Pod is the smallest deployable unit in
Kubernetes, and it can contain one or more
containers. It can contain multiple containers,
shared
storage, and network resources.
Container A container is a lightweight, standalone, and
executable
software package that includes everything needed to
run a piece of software. A single executable unit that
runs an application or
service within a virtualized environment.
Ans: A ReplicaSet ensures that a specific number of identical Pods are always running. If a Pod crashes or is deleted, the
ReplicaSet creates a new one to replace it, maintaining the desired number of Pods.
For example, if you want to maintain 3 Pods running at all times, the ReplicaSet will make sure the required number is
always up.
Ans: A ConfigMap is an API object used to store non-sensitive data such as configuration settings, environment variables,
and other config files. You can inject these configurations into Pods, which helps separate configuration from application
code.
Example YAML for using ConfigMap in Pods:
6. What is a ReplicaSet in Kubernetes?
7. What is the difference between a Pod and a Container?
apiVersion: v1
kind: Pod
metadata:
name: my-pod
spec:
containers:
- name: container-name
image: image
volumeMounts:
- name: volume-name
mountPath: /etc/configmap # Path where ConfigMap data will be mounted
volumes:
- name: volume-name
configMap:
name: configmap-name # Referencing the ConfigMap 'configmap-name'

Scope
Scaling
Lifecycle
Use Case
Resource
Sharing
Deployment
Runs one or more containers together on the
same node.
All containers in a Pod share the same
network IP, storage, and namespace.
Runs a single application or process within a virtualized
environment.
Containers run in isolated environments with their own
network and filesystem unless specified to share
resources. Containers are typically run in a Docker
engine or other
container runtimes but not necessarily in a Kubernetes
cluster. Containers are typically started, stopped, and
managed
individually but can be grouped together in Pods in
Kubernetes.
Pods are scheduled and run on nodes in a
Kubernetes cluster.
Pods are created, scheduled, and managed by
Kubernetes. They can be restarted and
managed as a group.
Pods can be scaled by increasing or
decreasing the number of replica pods.
Best for managing multiple containers that
Containers are scaled by creating more instances of the
container or managing them within a Pod.
Best for running a single application or process.
need to be tightly coupled and share
resources.
Ans: Helm is a package manager for Kubernetes. It simplifies the deployment and management of applications by using
charts, which are pre-configured Kubernetes resources.
It helps you define, install, and upgrade even the most complex Kubernetes applications using simple commands.
Ans: A StatefulSet is used to managestateful applications in Kubernetes. It ensures that Pods are deployed with a
consistent identity, including stable network IDs and persistent storage.
Unlike Deployments, Pods in a StatefulSet are assigned unique, persistent identifiers and ordered deployment.
Ans: The API Server is the central management point of the Kubernetes control plane. It exposes the Kubernetes API and is
the gateway for users and components to interact with the cluster.
It processes REST requests, validates them, and updates the cluster's state accordingly.
Ans: Namespaces in Kubernetes allow you to organize cluster resources by grouping them into virtual clusters. It’s useful
for isolating workloads and managing resources within a single cluster, especially in multi-tenant environments.
For example, you could have separate namespaces for development, staging, and production.
9. What is a StatefulSet?
10. What is Helm in Kubernetes?
8. What is Kubernetes Namespaces?
11. What is the role of the Kubernetes API Server?

16. What is a Job in Kubernetes?
Ans: A Job is a controller in Kubernetes that is used to run batch jobs. It ensures that a specified number of Pods are
completed successfully. Jobs are often used for tasks like data processing, backups, or database migrations.
12. What is Kubernetes Scheduler?
Ans: The Kubernetes Scheduler is responsible for assigning Pods to specific Nodes in the cluster. It does this by
considering factors such as available resources and constraints like taints, tolerations, and affinity.
18. What is an Ingress in Kubernetes?
Ans: An Ingress is an API object that manages external access to services in a Kubernetes cluster, typically HTTP. It
provides features like load balancing, SSL termination, and name-based virtual hosting.
17. What is a DaemonSet in Kubernetes?
Ans: A DaemonSet ensures that a specific Pod runs on all (or some) Nodes in a Kubernetes cluster. It's commonly used for
running background tasks like log collection or monitoring on every node.
15. what is the Control Plane in Kubernetes?
Ans:The Control Plane is the core of Kubernetes, and its most important component is the API server. The API server acts
as a gateway to interact with and manipulate the state of Kubernetes objects, such as pods, deployments, and services.
14. What is Horizontal Pod Autoscaling (HPA)?
Ans: HPA automatically scales the number of Pods in a deployment or ReplicaSet based on observed CPU utilization or
other selected metrics. It helps ensure that your application can handle varying levels of load efficiently without human
intervention.
13. What are Taints and Tolerations in Kubernetes?
Ans: Taints and tolerations help control which Pods can run on which Nodes. A taint is applied to a Node, and only Pods that
have matching toleration can be scheduled on that Node.
Without the scheduler, Pods wouldn’t be able to be placed efficiently across the Nodes in the cluster.
For example, if your app is under heavy load, HPA will automatically scale up the number of Pods.
This ensures that workloads are scheduled only on appropriate Nodes, helping with resource management.

For example, you can conﬁgure an Ingress to route traﬃc based on the URL path or hostname to different services inside
your cluster.
Ans: Container orchestration automates the deployment, scaling, and management of containers across multiple hosts. It
ensures load balancing, self-healing, and seamless communication between containers. Popular tools include Kubernetes,
Docker Swarm, and Apache Mesos.
19. Explain the concept of Container Orchestration.

20. What is a ReplicaSet in Kubernetes?
Ans: A ReplicaSet is a controller that ensures a speciﬁed number of replicas of a Pod are running at any given time. It helps
maintain the desired state of your application by replacing Pods that are deleted or failed.
Example YAML for ReplicaSet:
Kubernetes Interview Questions and Answers For Intermediates
apiVersion: apps/v1
kind: ReplicaSet
metadata:
name: my-replicaset
spec:
replicas: 3
selector:
matchLabels:
app: myapp
template:
metadata:
labels:
app: myapp
spec:
containers:
- name: my-container
image: my-image

21. What is a StatefulSet in Kubernetes?
Ans: A StatefulSet is a Kubernetes controller used to manage stateful applications. Unlike Deployments, StatefulSets
ensure that each Pod has a stable, unique network identity and storage. It is ideal for applications that require
persistent data, like databases.
22. How do you update a Deployment in Kubernetes?
Ans: To update a Deployment in Kubernetes, modify the desired specification in the Deployment YAML file and apply it
using kubectl apply. Kubernetes manages the rollout process, ensuring minimal downtime.
23. What is the purpose of a DaemonSet in Kubernetes?
Ans: A DaemonSet ensures that a copy of a Pod runs on every node in the cluster or specific nodes. It is commonly used for
cluster-wide services like log collection, monitoring, and networking tools.
To check the rollout status, use:
You can also use the kubectl set image command to update the container image:
Key features of StatefulSet include:
Ordered deployment and scaling of Pods.
Persistent storage using PersistentVolumeClaims (PVCs).
Consistent network identity for each Pod.
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: my-daemonset
spec:
selector:
matchLabels:
app: my-app
template:
metadata:
labels:
app: my-app
spec:
containers:
kubectl rollout status deployment/my-deployment
kubectl set image deployment/my-deployment my-container=my-image:v2
Example

24. What is a Kubernetes Secret?
Ans: A Secret in Kubernetes is an object used to store sensitive information such as passwords, OAuth tokens, and SSH
keys. Secrets help avoid exposing sensitive data directly in your application code or Pod specifications.
25. What is a ConfigMap in Kubernetes?
Ans: A ConfigMap is a Kubernetes object used to store non-confidential configuration data. It helps in decoupling
configuration settings from application code, making it easier to manage and update.
To use a Secret in a Pod, reference it in the Pod specification:
To create a Secret:
Example
- name: my-container
image: my-image
apiVersion: v1
kind: Pod
metadata:
name: secret-example
spec:
containers:
- name: my-app
image: my-image
env:
- name: SECRET_USERNAME
valueFrom:
secretKeyRef:
name: my-secret
key: username
apiVersion: v1
kind: Pod
metadata:
name: my-pod
spec:
containers:
- name: container-name
image: image
volumeMounts:
- name: volume-name
mountPath: /etc/configmap
kubectl create secret generic my-secret --from-literal=username=admin --from-literal=password=pass123

26. What are Taints and Tolerations in Kubernetes?
Ans: Taints and Tolerations control which Pods can be scheduled on specific nodes. Taints are applied to nodes to repel
Pods, while Tolerations are applied to Pods to allow them to be scheduled on tainted nodes.
27. What is a PersistentVolume (PV) in Kubernetes?
Ans: A PersistentVolume (PV) is a piece of storage in a Kubernetes cluster that has been provisioned for use by Pods. PVs
provide storage resources that persist beyond the lifecycle of individual Pods.
28. What is the purpose of a PersistentVolumeClaim (PVC)?
Ans: A PersistentVolumeClaim (PVC) is a request for storage by a Pod. It allows Pods to use PersistentVolumes by
claiming storage resources based on specific requirements like size and access modes.
They can be dynamically provisioned or statically defined:
Example
Example of a Taint:
Example of a Toleration:
tolerations:
- key: "key"
operator: "Equal"
value: "value"
effect: "NoSchedule"
apiVersion: v1
kind: PersistentVolume
metadata:
name: my-pv
spec:
capacity:
storage: 10Gi
accessModes:
- ReadWriteOnce
hostPath:
path: "/data/pv"
volumes:
- name: volume-name
configMap:
name: configmap-name
kubectl taint nodes node1 key=value:NoSchedule

29. How do you perform a rolling update in Kubernetes?
Ans: A rolling update in Kubernetes allows you to update a Deployment without downtime. It gradually replaces old Pods
with new ones while keeping the application available.
30. What is Kubernetes Horizontal Pod Autoscaler (HPA)?
Ans: The Horizontal Pod Autoscaler (HPA) in Kubernetes automatically adjusts the number of Pods in a Deployment,
ReplicaSet, or StatefulSet based on CPU or memory usage or custom metrics.
Update the Deployment YAML ﬁle or use
Monitor the update with
Steps:
Example conﬁguration:
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: my-pvc
spec:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 5Gi
apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
name: my-hpa
spec:
scaleTargetRef:
apiVersion: apps/v1
kind: Deployment
name: my-deployment
minReplicas: 2
maxReplicas: 10
metrics:
- type: Resource
resource:
name: cpu
target:
type: Utilization
averageUtilization: 50
kubectl set image.
kubectl rollout status.

31. What is Kubernetes Ingress?
Ans: Ingress in Kubernetes manages external access to services within a cluster, typically HTTP or HTTPS traffic. It
provides routing rules to expose multiple services under a single IP address or domain name.
32. What is Kubernetes Pod Affinity?
Ans: Pod Affinity specifies rules for placing Pods close to or far from other Pods. It helps optimize resource usage and
network latency.
33. What are Kubernetes Init Containers?
Ans: Init Containers run before the main application container in a Pod. They prepare the environment, such as pulling
configuration files or waiting for a dependency to become available.
Example
Example
Example
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: example-ingress
spec:
rules:
- host: example.com
http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: my-service
port:
number: 80
affinity:
podAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchLabels:
app: frontend
topologyKey: "kubernetes.io/hostname"

34. What is a Network Policy in Kubernetes?
Ans: A Network Policy in Kubernetes controls traﬃc between Pods. It ensures secure communication by deﬁning ingress
and egress rules based on Labels or namespaces.
35. Explain how to set up and use Role-Based Access Control (RBAC) in Kubernetes.
Ans: RBAC in Kubernetes controls user and service access to resources using roles and bindings. Create a Role, assign
permissions, and bind it to users or service accounts with RoleBinding.
Example
Example Role
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: allow-specific
spec:
podSelector:
matchLabels:
app: frontend
policyTypes:
- Ingress
ingress:
- from:
- podSelector:
matchLabels:
app: backend
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
namespace: default
name: pod-reader
rules:
- apiGroups: [""]
initContainers:
- name: init-container
image: busybox
command: ['sh', '-c', 'echo Preparing environment']

Bind the Role:
Kubernetes Interview Questions and Answers For Experienced
36. How does Kubernetes handle secrets at runtime securely?
Ans: Kubernetes uses Secrets to manage sensitive data like passwords and API keys. At runtime, secrets are mounted into
Pods as files or exposed as environment variables. To secure them:
37. What is the difference between ReplicaSet and ReplicationController?
Ans: Both ReplicaSet and ReplicationController ensure a specified number of Pod replicas are running. Key differences are:
Feature
Introduction
Selector
ReplicaSet
Introduced in Kubernetes 1.2
Supports both '=', 'in', and 'notin' for label
selectors
Supports rolling updates for deployments
Used with Deployments to manage replicas
ReplicationController
Available in earlier versions of Kubernetes
Only supports '=' selector for labels
Rolling Updates
Usage
Does not support rolling updates
Mainly used for managing replica sets
(deprecated)
Deprecated and not recommended for new
clusters
Support
Features
Deployment Integration
for New Actively maintained and supported new
features
Works seamlessly with Deployments forIt cannot be directly used with Deployments
updates
Encrypt secrets at rest using EncryptionConfiguration.
Use role-based access control (RBAC) to restrict access.
Limit secret exposure by binding only to necessary Pods.
resources: ["pods"]
verbs: ["get", "list", "watch"]
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: read-pods
namespace: default
subjects:
- kind: User
name: john
roleRef:
kind: Role
name: pod-reader
apiGroup: rbac.authorization.k8s.io

41. What is Kubernetes Admission Controller?
39. What is Kubernetes CustomResourceDefinition (CRD)?
Ans: A CustomResourceDefinition (CRD) is used to create custom resources in Kubernetes, enabling you to extend
Kubernetes functionalities. CRDs are managed like native Kubernetes resources through the Kubernetes API.
40. How do you implement canary deployments in Kubernetes?
Ans: Canary deployments in Kubernetes can be implemented using:
38. What are the challenges of running a multi-cluster Kubernetes environment?
Ans: Running multi-cluster Kubernetes environments involves challenges like:
Ensuring consistent configurations and policies across clusters.
Managing inter-cluster communication and networking.
Balancing workloads and scaling effectively.
Monitoring and troubleshooting across multiple clusters.
Updating the Deployment with a small number of replicas for the new version.
Using Ingress or Service routing to split traffic between the old and new versions.
Example
Example with Deployment:
spec:
replicas: 2
template:
spec:
containers:
- name: app
image: app:v2
apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
name: myresources.example.com
spec:
group: example.com
names:
kind: MyResource
plural: myresources
scope: Namespaced
versions:
- name: v1
served: true
storage: true

Ans: etcd stores the cluster’s state and must be secured:
Enable TLS for communication.
Restrict access to etcd using firewalls or network policies.
Encrypt etcd data at rest with Kubernetes encryption providers.
Ans: Kubernetes ensures self-healing by:
Restarting failed containers using Liveness Probes.
Rescheduling Pods on healthy nodes if a node fails.
Maintaining desired Pod states through controllers like ReplicaSet.
Ans: kube-proxy manages network rules on nodes to enable communication between services and Pods. It handles:
IP-based traffic routing using iptables or IPVS.
Load balancing for service traffic.
Ans: RuntimeClasses allow you to define different container runtimes for Pods. This enables the use of specialized
runtimes like gVisor or Kata Containers for enhanced security or performance.
Ans: Admission Controllers are plugins that intercept API server requests to enforce policies or add default configurations.
Examples include:
ValidatingAdmissionWebhook: Validates custom rules.
ResourceQuota: Enforces resource limits.
Ans: Kubernetes Federation enables the management of multiple clusters as a single entity. It provides centralized control
for tasks like:
Deploying applications across clusters.
Disaster recovery by replicating workloads.
Global load balancing.
43. What is the Kubernetes Federation?
45. What are Kubernetes RuntimeClasses?
46. What is the role of kube-proxy in Kubernetes?
42. How does Kubernetes implement self-healing?
44. How do you secure etcd in a Kubernetes cluster?
Example
apiVersion: node.k8s.io/v1
kind: RuntimeClass
metadata:
name: gvisor
handler: runsc

47. How can you debug a Kubernetes Pod?
Ans: To debug a Pod:
49. How do you monitor a Kubernetes cluster?
Ans: To monitor a Kubernetes cluster:
50. How do you handle node scaling in Kubernetes?
Ans: Node scaling can be managed using:
48. What are Kubernetes node affinity and anti-affinity?
Ans: Node Affinity schedules Pods on specific nodes based on labels. Anti-affinity avoids placing Pods on specific nodes.
Check Pod logs:
Inspect Pod events:
Access the container:
Use tools like Prometheus and Grafana for metrics.
Leverage Kubernetes Dashboard for real-time monitoring.
Enable logging using Fluentd, ELK, or Loki stacks.
Cluster Autoscaler: Automatically adds or removes nodes based on Pod demands.
Manual scaling: Adjust the number of nodes using the cloud provider’s CLI or console.
This article explored key Kubernetes interview questions that are commonly asked during interviews. From container
orchestration and pod management to cluster scaling and networking, these questions test your understanding of
Kubernetes fundamentals. Whether you're a fresher or an experienced professional, preparing for these questions will
help you excel in your Kubernetes interview.
Ready to master Kubernetes? Enroll in the Scholarhat Docker and Kubernetes Coursetoday and unlock your full potential in
Kubernetes!
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: disktype
operator: In
values:
- ssd
kubectl logs pod-name.
kubectl describe pod pod-name.
kubectl exec -it pod-name -- /bin/sh.
Example
Summary

Kubernetes Interview Questions PDF By ScholarHat

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