Kubernetes Interview Q&As

The Only 20 Kubernetes Interview Q&As You Need To Bag Your Dream job in 2021

Of late, Kubernetes has become a term that has become a buzzword in the industry. And if you are a cloud professional, then the term would be part of your daily work glossary.

But why is it a topic of interest?

Ever since its inception in 2015, Kubernetes has become the most sought after computer application. Along with its meteoric rise, it also has become a skill that is highly valuable in today’s corporate world. 

If you’re an aspiring Kubernetes professional looking to hone your interview skills and prepare for them, here are the questions and answers you should study. 

Without taking much of your time, let’s begin! 

Here are 20 questions that are worth your time. 

  1. What is Kubernetes?

    Kubernetes is an open-source container orchestration platform that automates many of the processes involved in deploying, managing, and scaling containerized applications. 

    It helps manage several containers with ease. It can handle the grouping of containers which provides for logical units that can be managed. 

    Kubernetes is written in the Go programming language. 

    Kubernetes is also called K8 or Kube. 

  2. What is ‘Orchestration’ in IT and DevOps?

    Orchestration is the automated configuration, management, and coordination of computer systems, applications, and services. It helps in managing complex tasks and workflows with ease when it comes to IT. 

    It also helps you to streamline and optimize repeatedly occurring processes and workflows. This can support a DevOps approach and help your team deploy applications faster. 

    Orchestration is also helpful in automating IT processes namely server provisioning, incident management, cloud orchestration, database management, application orchestration, and other tasks and workflows. 

  3. Mention a few features of Kubernetes

    The features of Kubernetes are mentioned below- 

    • Automated Scheduling –  Advanced scheduler to launch containers on cluster nodes 
    • Self- Healing – Can reschedule, replace, and restart containers that have died 
    • Automated rollouts and rollbacks – Assists rollouts and rollbacks 
    • Horizontal Scaling – Capabilities of scaling applications up or down as per requirements 

    Here’s an easy way to kickstart your career in Kubernetes

  4. Differentiate between Kubernetes and Docker

    Kubernetes  Docker 
    • A series of manual steps to setup Kubernetes Master and nodes components in a cluster of nodes
    • Kubernetes is compatible with various platforms. From your laptop to VMs on the cloud provider to a rack of bare metal servers. To set up a single node K8s cluster, you can use a MiniKube
    • When it comes to data volume, docker shares storage volumes between multiple containers in the same pod
    • Offers an inbuilt tool for logging and monitoring
    • You can manually configure your load balancing settings
    • Optimized for multiple smaller clusters of software development life cycle
    • Has low fault tolerance
    • Supports up to 5000 nodes
    • Kubernetes has a high container limit which is 3,00,000
    • Talking about compatibility, Kubernetes is more comprehensive and highly customizable
    • Installing Docker is a matter of one-liner command on Linux Platform like Debian, Ubuntu, and CentOS
    • To install a single-node Docker swarm or Kubernetes cluster, you can use Docker for Mac and Docker for Windows 
    • When it comes to data volume, Kubernetes shares storage volume with any container 
    • Permits use of a third-party tool
    • Docker does auto load balancing   
    • Optimized for a single large cluster 
    • Has high fault tolerance 
    • Can support up to only 2000 nodes 
    • The container limit for Docker is comparatively less. It is just 95,000
    • Docker compatibility is less extensive and customizable 
  5. What is a node in Kubernetes?

    A node is the smallest unit of hardware. It is a logical collection of IT resources that assist one or more containers. Nodes have the essential services to run Pods. Pods are Kubernetes units of containers. 

    These nodes help in communicating with master components, configure networking and run designated workloads. A node can host one or multiple Pods. 

    Each of the Kubernetes has services to create the runtime environment and assist pods. The components include Docker, Kube-proxy, and kubelet. 

  6. What are Daemon sets?

    A Daemon set is a group of pods that run on the host only once. They are utilized for host layer attributes like a network or tracking a network where you don’t need to run a node more than once. 

  7. Define Heapster in Kubernetes

    A Heapster is a metrics collection and performance monitoring system for data that are collected by the Kublet. 

  8. What is Kubelet?

    A Kubelet is a service agent which controls and manages a group of pods by checking pod specifications using Kubernetes. 

    The kubelet runs on each node and allows communication between a master node and a slave node. 

  9. What is Kubectl?

    Kubectl is a command-line tool used to run commands against Kubernetes clusters. The ‘ctl’ in Kubectl stands for control. 

    The format of kubectl command is given below- 

    kubectl[command][type][name][flags]  

  10. What is Google Container Engine?

    Google Container Engine (GKE) is a cluster management and container orchestration system built to run and manage Docker containers. 

    It is powered by the open-source Kubernetes system created by Google. It can efficiently manage containers and can be utilized for on-premises, hybrid cloud, or public cloud infrastructure. 

  11. What is a namespace in Kubernetes?

    Namespaces are the organizational mechanism that Kubernetes provides to categorize, filter by, and manage random groups of objects within a cluster. 

    Namespaces allow you to group objects in conjunction so it becomes easy to filter and control them as one unit. 

  12. Define ClusterIP

    Cluster IP is a virtual IP that is assigned by the K8s to a service. It is K8s internal IP. A cluster IP makes it attainable from any of the Kubernetes cluster’s nodes. 

    The use of virtual IP addresses for this motive makes it possible to have numerous pods expose the same port on the same node.  All the pods will be reachable via a unique IP address. 

    The cluster IP is stable and never changes in the service lifecycle.  Two different pods can communicate using this IP. However, we recommend using a cluster DNS service. 

  13. Specify the advantages of Kubernetes

    The advantages of Kubernetes is as follows- 

    • Airtight Application security 
    • Save time and money supporting giant projects 
    • Prevent errors from causing downtime 
    • Reduce the risk of errors and accelerate time to market 
    • Lower deployment costs 
    • Manage microservices architecture at a higher scale 
    • It is open source 
  14. Explain Ingress Network

    Ingress Network is a set of rules which permit permission for connections into the Kubernetes cluster. 

  15. What is the use of a Load Balancer?

    A load balancer is a piece of hardware that acts as a reverse proxy to distribute network or application traffic across different servers. 

    It is used to improve the concurrent user capacity and overall dependability of applications. A load balancer helps to improve them by distributing the workload across multiple servers, decreasing the overall burden placed on each server. 

  16. What is MiniKube?

    Minikube is a utility that can be used to run Kubernetes on your local device. It creates a single node cluster contained in a virtual machine (VM). 

    This cluster lets you display the Kubernetes operations without needing the time and resource-consuming installation of full-blown Kubernetes. 

  17. What is ETCD?

    ETCD is an open-source, distributed, consistent key-value store for shared configuration, service discovery, and scheduler coordination of distributed systems or clusters of machines.

    It helps to facilitate safer automatic updates, coordinates work being scheduled to hosts, and assists in the setup of overlay networking of containers. 

    It is written in the Go programming language. 

  18. What is a Kube proxy?

    Kube proxy is the application of a load balancer and network proxy used to support service abstraction with other networking operations. It is responsible for directing traffic to the right container based on the IP and port number of incoming requests. 

  19. How does DNS work in Kubernetes?

    DNS is in-built in Kubernetes. It is launched automatically when Kubernetes is set up for the first time. 

    Kubernetes DNS arranges a DNA pod and service on the cluster. It setups kubelets to convey individual containers to use the DNS Service’s IP to settle DNS names. 

    Every service defined in the Kubernetes cluster(including the DNS server) is allocated a DNS name. 

    By default, a client pod’s DNS search list will include the pod’s namespace and the cluster’s default domain. 

  20. Mention the disadvantages of Kubernetes

    The disadvantages of Kubernetes is mentioned below- 

    • Switching to stateless requires tough efforts 
    • Limited functionality according to the availability in the Docker API 
    • Highly complicated installation and configuration process 
    • Not compatible with existing Docker CLI and compose tools 
    • Complex manual cluster deployment and automatic horizontal scaling set up 

    Of late, Kubernetes has become a term that has become a buzzword in the industry. And if you are a cloud professional, then the term would be part of your daily work glossary. 

    But why is it a topic of interest? 

    Ever since its inception in 2015, Kubernetes has become the most sought after computer application. Along with its meteoric rise, it also has become a skill that is highly valuable in today’s corporate world. 

    If you’re an aspiring Kubernetes professional looking to hone your interview skills and prepare for them, here are the questions and answers you should study. 

    Without taking much of your time, let’s begin! 

    Here are 20 questions that are worth your time.

Closure

Kubernetes is a flourishing domain and if you want to make a career in it, the opportunities are a dime a dozen. The above mentioned 20 questions will help you prepare for the interview well. If you are an experienced Kubernetes professional, it will help brush up on your basics. 

Do let us know what we have missed. Your feedback is appreciated. 

It ‘s au revoir for now!

Kubernetes is a flourishing domain and if you want to make a career in it, the opportunities are a dime a dozen. The above mentioned 20 questions will help you prepare for the interview well. If you are an experienced Kubernetes professional, it will help brush up on your basics. 

Do let us know what we have missed. Your feedback is appreciated. 

It ‘s au revoir for now!

Author's Bio
Agilitics

We strive to provide business professionals with the skills and knowledge necessary to increase work performance and drive greater return on investment for the global customers we support. Agilitics delivers customized technology and management training solutions to large corporations and government agencies around the world.