Docker Online Training | Kubernetes Online Training

1. Docker vs. Kubernetes What is Docker? There are two ways to see Docker. The first approach is to view Docker containers as really light virtual machines, while the second approach is to view Docker as a platform for packaging and delivering software. The latter approach has proven much more useful for human developers and has resulted in widespread adoption of the technology. Let's take a closer look at the two different views. An overview of Docker containers Traditionally, cloud service providers have used virtual machines to isolate running applications from each other. A hypervisor, or host operating system, provides a virtual processor, memory, and other resources to many guest operating systems. Each guest operating system operates as if it were running on actual physical hardware, and ideally is unaware that other guests are running on the same physical server.

2. On the other hand, when we run containerized applications, we virtualize the operating system (your standard libraries, packages, etc.) itself, not the hardware. Now, instead of providing virtual hardware to a virtual machine, you are providing a virtual operating system to your application. You can run multiple applications and impose limitations on their resource usage if you wish, and each application will run regardless of the hundreds of other containers it runs. What is Kubernetes? Kubernetes uses containerization technology, as described above. It allows us to run containers on multiple compute nodes (these can be virtual machines or bare- metal servers). Once Kubernetes takes control of a cluster of nodes, the containers can then be expanded or destroyed as needed at any time. The official website clearly states Kubernetes' objective: "an open source system to automate the deployment, scaling and management of containerized applications." So far, we've only represented a naïve glimpse of Kubernetes as the automation of a bunch of container creation. An application must have storage and there are DNS records to manage. You need to make sure that the participating compute nodes are properly connected to each other, etc. Having a set of different nodes instead of a single host leads to a completely different set of problems. Kubernetes architecture: a brief overview There are two basic concepts to know about a Kubernetes cluster. The first is the knot. This is a common term for virtual machines and / or bare-metal servers managed by Kubernetes. The second term is the pod, which is a basic unit of deployment in Kubernetes. A pod is a collection of associated Docker containers that must coexist. For example, your web server may need to be deployed with a redis caching server so that you can encapsulate them in a single module. Kubernetes deploys them side by side. If that makes your job easier, you can totally imagine a pod made up of a single container and that would be nice.

3. Going back to nodes, there are two types of nodes. One is the main node, where the heart of Kubernetes is installed. It controls the scheduling of pods on different work nodes (just alias nodes), where your application actually runs. The job of the master node is to ensure that the desired state of the cluster is maintained. Differences between Kubernetes and Docker In principle, Kubernetes can work with any containerization technology. Rkt and Docker are two of the most popular options that Kubernetes can integrate with. However, Docker has the most spirit sharing, which has resulted in much more effort to perfect the integration between it and Kubernetes than any other containerization technology. Likewise, Docker Inc., the company behind Docker, offers its own container orchestration engine, Docker Swarm. If someone were nervous about adopting

4. Kubernetes for their Docker product, that last point should dispel any doubt. The two projects embraced wholeheartedly and benefited enormously from this symbiosis. Similarities between Kubernetes and Docker These projects are more than technologies; it's a community of people who, despite their differences, are among the brightest minds in the industry. When like-minded individuals collaborate, they exchange brilliant ideas and learn from each other's best practices. Here are some of the ideas that Kubernetes and Docker share: Their love for architecture based on microservices (more on that later). Their love for the open source community. Both are large open source projects. They are largely written in the Go programming language, which allows them to be shipped as small, lightweight binaries. They use human-readable YAML files to specify application stacks and their deployments. For More Information about Docker & Kubernetes Online Training ClickHere Ph No: +91-9989971070, E-Mail ID: online@visualpath.in