20 Google Kubernetes Engine Interview Questions and Answers

Google Kubernetes Engine (GKE) is a popular container orchestration tool used by developers to manage and deploy containerized applications. If you’re applying for a position that involves GKE, it’s important to be prepared to answer questions about it during your interview. In this article, we’ll review some of the most common GKE interview questions and provide tips on how to answer them.

Google Kubernetes Engine Interview Questions and Answers

Here are 20 commonly asked Google Kubernetes Engine interview questions and answers to prepare you for your interview:

1. What is Google Kubernetes Engine?

Google Kubernetes Engine is a powerful cluster manager and orchestration system for running Docker containers. It is designed to make it easy to deploy and manage containerized applications at scale.

2. How does the scheduling of workloads happen in GKE?

Workloads in GKE are scheduled using the Kubernetes scheduler. The scheduler looks at the resources that are required by each workload and then tries to find the best place to run it based on available resources.

3. Can you explain what a pod is in the context of GKE?

A pod is a group of one or more containers that are deployed together on a single node in a Google Kubernetes Engine cluster. Pods are the smallest deployable units in GKE and are used to encapsulate and isolate application containers.

4. What are some key features of pods in GKE?

Pods in GKE are self-contained units that can contain one or more containers. Pods allow you to tightly couple containers that need to share resources, such as storage or networking. Pods also enable you to replicate your application across multiple nodes in a cluster.

5. What is a deployment controller?

A deployment controller is a type of controller that is responsible for creating and managing deployments in a Google Kubernetes Engine cluster. A deployment controller can be used to create and manage both new deployments and existing deployments.

6. What is an ingress and how can it be used with GKE?

An ingress is a network gateway that provides access to services running inside a cluster. It can be used to load balance traffic and provide a single point of entry to a cluster. Ingress can be used with GKE to provide a way to access services running inside the cluster from outside the cluster.

7. How do you configure load balancing for your application running on GKE?

You can configure load balancing for your application running on GKE by creating a LoadBalancer Service object. This will create a Google Cloud Load Balancer that will distribute traffic evenly across the pods in your deployment.

8. When should you use persistent volumes in GKE?

You should use persistent volumes in GKE when you need to store data that needs to be persisted even if the pod is deleted. For example, if you are running a database in a pod, you will want to use a persistent volume so that the data is not lost if the pod is deleted.

9. Is it possible to create custom network policies in GKE? If yes, then how?

Yes, it is possible to create custom network policies in GKE. You can do this by creating a Kubernetes Network Policy object, which will then specify the desired policy.

10. What’s the difference between ephemeral storage and persistent disk storage in GKE?

Ephemeral storage is a type of storage that only lasts for the duration of a single pod’s lifetime. This means that any data stored in ephemeral storage will be lost when the pod is deleted. Persistent disk storage, on the other hand, is designed to be long-term storage that can outlast the lifetime of a single pod. This makes persistent disk storage a better option for storing data that needs to be preserved even if the pod is deleted.

11. What are some important configurable parameters that can affect the performance of your containerized applications running on GKE?

There are a few important configurable parameters that can affect the performance of your containerized applications running on GKE:

– The number of replicas: This parameter determines how many copies of your application will be running. More replicas will generally mean better performance, but it also depends on your application and how it scales.

– The CPU and memory limits: These parameters determine the maximum amount of resources that your application can use. If your application exceeds these limits, it may be throttled or even killed.

– The image: The base image that your application is built on can also affect performance. For example, using a lightweight image like Alpine Linux can help improve performance.

12. Can you give me some examples of real-world applications that use Google Kubernetes Engine?

Yes, some real-world applications that use Google Kubernetes Engine include:

– Netflix
– Etsy
– The New York Times
– Spotify
– Ubisoft

13. How would you troubleshoot issues when deploying microservices using GKE?

There are a few different ways that you can troubleshoot issues when deploying microservices using GKE. First, you can check the container logs to see if there are any errors being reported. You can also use the kubectl command-line tool to get more information about the status of your deployment. Finally, if you are still having trouble, you can reach out to the Google Kubernetes Engine support team for help.

14. What are nodes in GKE?

Nodes in GKE are individual virtual machines that are used to run your applications. You can choose to have a single node or multiple nodes in your cluster, and each node will have a unique IP address.

15. What is a cluster and how does it relate to GKE?

A cluster in GKE is a group of Compute Engine instances that you can manage as a single unit. Clusters can range in size from a single instance to thousands of instances. You can use clusters to improve the availability and performance of your applications.

16. Where does GKE store node configuration data?

GKE stores node configuration data in JSON files called “config maps.” These config maps are stored in a GKE-specific location in Google Cloud Storage (GCS).

17. What is a master node and how does it differ from other types of nodes in GKE?

A master node is the heart of a Google Kubernetes Engine cluster. It is responsible for managing the cluster and all of the workloads running on it. Other types of nodes in GKE include worker nodes, which are used to run applications and services, and infra nodes, which are used to manage and monitor the cluster.

18. What is the default resource quota for CPU and memory resources available to each user in GKE?

The default resource quota for CPU resources is 0.6 cores, and the default resource quota for memory resources is 1.5GB.

19. What happens if a node goes down while running containers on GKE? Is there any way to prevent this from happening?

If a node goes down while running containers on GKE, the containers will be automatically restarted on another node in the cluster. There is no way to prevent this from happening, but it is not typically a cause for concern as the containers will be quickly restarted on another node.

20. What are the different types of security measures supported by GKE?

GKE supports a number of security measures to help protect your containerized applications. These include role-based access control, network security policies, and encrypted communications.