Q1) What are the features of Kubernetes?

Ans: The features of Kubernetes, are as follows:

Q2) How is Kubernetes different from Docker Swarm?

Ans: Docker Swarm is Docker’s native, open-source container orchestration platform that is used to cluster and schedule Docker containers. Swarm differs from Kubernetes in the following ways:

• Docker Swarm is more convenient to set up but doesn’t have a robust cluster, while Kubernetes is more complicated to set up but the benefit of having the assurance of a robust cluster.
• Docker Swarm can’t do auto-scaling (as can Kubernetes); however, Docker scaling is five times faster than Kubernetes.
• Docker Swarm doesn’t have a GUI; Kubernetes has a GUI in the form of a dashboard.
• Docker Swarm does automatic load balancing of traffic between containers in a cluster, while Kubernetes requires manual intervention for load balancing such traffic.
• Docker requires third-party tools like ELK stack for logging and monitoring, while Kubernetes has integrated tools for the same.
• Docker Swarm can share storage volumes with any container easily, while Kubernetes can only share storage volumes with containers in the same pod.
• Docker can deploy rolling updates but can’t deploy automatic rollbacks; Kubernetes can deploy rolling updates as well as automatic rollbacks.

Q3) What is the difference between deploying applications on hosts & containers?

Ans: Volume Name: pv-analytics, Storage: 100Mi, Access modes: ReadWriteMany, Host Path: /pv/data-analytics

Refer to the above diagram. The left side architecture represents deploying applications on hosts. So, this kind of architecture will have an operating system and then the operating system will have a kernel which will have various libraries installed on the operating system needed for the application. So, in this kind of framework you can have n number of applications and all the applications will share the libraries present in that operating system whereas while deploying applications in containers the architecture is a little different.

This kind of architecture will have a kernel and that is the only thing that’s going to be the only thing common between all the applications. So, if there’s a particular application which needs Java then that particular application we’ll get access to Java and if there’s another application which needs Python then only that particular application will have access to
Python.

The individual blocks that you can see on the right side of the diagram are basically containerized and these are isolated from other applications. So, the applications have the necessary libraries and binaries isolated from the rest of the system, and cannot be encroached by any other application.

Q4) What is Container Orchestration?

Ans: Consider a scenario where you have 5-6 microservices for an application. Now, these microservices are put in individual containers, but won’t be able to communicate without container orchestration. So, as orchestration means the amalgamation of all instruments playing together in harmony in music, similarly container orchestration means all the services in individual containers working together to fulfill the needs of a single server.

Q5) What do you know about clusters in Kubernetes?

Ans: The fundamental behind Kubernetes is that we can enforce the desired state management, by which I mean that we can feed the cluster services of a specific configuration, and it will be up to the cluster services to go out and run that configuration in the infrastructure.

So, as you can see in the above diagram, the deployment file will have all the configurations required to be fed into the cluster services. Now, the deployment file will be fed to the API and then it will be up to the cluster services to figure out how to schedule these pods in the environment and make sure that the right number of pods are running.

So, the API which sits in front of services, the worker nodes & the Kubelet process that the nodes run, all together make up the Kubernetes Cluster.