Kubernetes Interview Questions For Experienced

34. Explain the concept of a Custom Operator in Kubernetes.

Utilizing the Kubernetes API, operators automate procedures like application deployment, scaling, and governance, offering a smooth and integrated approach to resource management. Operators usually set up as custom controllers and extend the Kubernetes API with new resources and specialized logic for their management.

35. Describe the internals of the Kubernetes control plane.

Worker nodes, pods, and other cluster resources are administered by the Kubernetes control plane. It receives data regarding cluster activity, requests from both internal and external sources, and various other things. Then, it applies this information to move the cluster resources from their current state to the desired state.

36. What is the purpose of the Kubernetes API server?

As the front end to the cluster’s shared state, the API server manages REST operations and serves as the hub through which all other components communicate. Its main responsibility is to receive and handle HTTP requests in the form of API calls, which come from consumers or other Kubernetes system components. The Kubernetes API server is crucial to the validation as well as the configuration of data for different API objects, including pods, services, replication controllers, and more.

37. How does Kubernetes handle rolling back deployments?

In Kubernetes, you can roll back a deployment using the `kubectl rollout} command. This command provides an array of options to control rollbacks, like `kubectl rollout undo`, which flips back the current deployment to the previous revision. You can also use the `–to-revision} flag to specify a specific revision.

kubectl rollout undo deployment <deployment-name>

kubectl rollout undo deployment <deployment-name> –to-revision=<revision-number>

38. Explain the concept of Pod Disruption Budgets.

It is intended for application owners who want to build highly available applications and also serves as a guide for cluster administrators who are building automated cluster actions such as autoscaling and upgrades. Pod disruption budgets, or PDBs for short, are policies that specify the desired state of the cluster and the orchestrators’ attempt to maintain it. For PDBs, this consists of defining a maximum quantity of failed pods or the lowest number of pod replicas that must stay in the cluster at any given time.

39. What is the role of the kube-controller-manager?

As a daemon, the Kubernetes controller manager incorporates all of the basic control loops that make up Kubernetes. A control loop in robotics and automation is an ongoing mechanism that manages the state of the system. In Kubernetes, a controller is a control loop that keeps an eye on the cluster’s shared state through the api server and makes modifications to bring the current state into line with the desired state. Some of the controllers that come packaged with Kubernetes are the replication controller, endpoints controller, namespace controller, and service accounts controller.

40. Describe the role of kube-apiserver in the Kubernetes architecture.

The frontend to the cluster’s shared state which all other components interact with is the Kubernetes API server. It handles REST operations, validation of data and configuration of various API objects like pods, services, and replication controllers, and provides an encompassing interface for managing the cluster’s overall state and allowing communication with all components.

41. How does Kubernetes handle node failures and resiliency?

Whenever a node fails or a container becomes hazardous, Kubernetes makes sure that a sufficient amount of replicas is maintained by launching new replicas on numerous servers, which maintains continuous availability.

Here are some key mechanisms and strategies that Kubernetes employs:

• Node Health Monitoring
• Pod Restart Policies
• Replication and Desired State
• Pod Disruption Budgets
• Node Pools and Multi-Cloud Deployments

42. Explain how to set up and use Role-Based Access Control (RBAC) in Kubernetes.

Initially choose a few broad user categories and the degree of access that each one needs. These choices will be based on the method of authentication you decide as well as the demands of your organization. After you have made the decisions, you can set up role bindings for every group of user.

43. What is the role of the Cloud Controller Manager in a cloud-based Kubernetes cluster?

The cloud-controller-manager, a crucial Kubernetes control plane component, encapsulates cloud-specific control logic. This manager facilitates the integration of your cluster with the API of your cloud provider, effectively segregating components that interact with the cloud platform from those that solely interact with the Kubernetes cluster. As part of its capabilities, the cloud controller manager regulates the Node controller, which is in charge of tasks like removing deleted Kubernetes nodes from the cloud environment and setting up cloud infrastructure technologies.

44. Describe a few important Kubectl commands.

The following are important Kubectl commands:

• kubectl api-resources
• kubectl autoscale
• kubectl annotate
• kubectl cluster-info
• kubectl attach
• kubectl apply
• kubectl update
• kubectl edit
• kubectl config set
• kubectl config
• kubectl config current-context.

45. What is Helm of Kubernetes?

Helm is a package manager for Kubernetes that makes application deployment and management more simple. By providing a templating system, parameterization, and versioning for Kubernetes manifests, Helm increases deployment process and makes it possible to define, install, and upgrade even the most complex Kubernetes applications using the pre-configured packages called “charts.”

Helm’s main features are as follows:

• Charts
• Templating
• Repositories
• Reusability
• Parameterization
• Dependency Management
• Release Management

Kubernetes is a powerful open-source platform for automating deployment, scaling, and operations of application containers across clusters of hosts. It provides a container-centric infrastructure that is efficient, making it a leading choice for managing complex applications. Derived from the Greek word meaning “captain,” “helmsman,” or “governor,” Kubernetes has become indispensable in the world of cloud-native applications. With its automation, scalability, and ease of deployment, Kubernetes offers unparalleled efficiency for developers and operations teams alike. Kubernetes is extensively used by top companies like Google, Red Hat, VMware, IBM, and many others due to its robust features and exceptional performance.

In this article, we will provide the Top 40 Kubernetes Interview Questions and Answers tailored for both freshers and experienced professionals. Here, we cover everything, including fundamental Kubernetes concepts, Kubernetes architecture, pods, StatefulSets, Monitoring and Logging, deployment strategies, and more, that will surely help you crack DevOps interviews.