In this article, we will be covering all the details about containers i.e. how they actually work behind the scene and all the parts it consists of. We will also learn why Docker is so blazingly fast.
By the end of this article you will be able to create your own custom container. Excited already? Well you should definitely be.
We will see why K8S depreciated Docker and adopted CRI-O & we will also see how to set up a multi-node Kubernetes cluster using CRI-O
What are containers?
Containers are a solution to the problem of how to get the software to run reliably when moved from one computing environment to another. Container technology is almost as old as VMs, although the IT industry wasn’t employing containers until 2013–14 when Docker and Kubernetes, and other tech made waves were born that caused craziness in the industry. Containers have become a major trend in software development as an alternative or companion to Virtual Machine. Containerization helps developers to create and deploy applications faster and more securely.
Why do you need them?
Containers are a solution to the problem of how to get the software to run reliably when moved from one computing environment to another. This could be from a developer’s laptop to a test environment, from a staging environment into production, and perhaps from a physical machine in a data center to a virtual machine in a private or public cloud.
Problems arise when the supporting software environment is not identical, says Docker creator Solomon Hykes. “You’re going to test using Python 2.7, and then it’s going to run on Python 3 in production and something weird will happen. Or you’ll rely on the behavior of a certain version of an SSL library and another one will be installed. You’ll run your tests on Debian and production is on Red Hat and all sorts of weird things happen.”
And it’s not just different software that can cause problems, he added. “The network topology might be different, or the security policies and storage might be different but the software has to run on it.”
#kubernetes #docker #podman #containers #devops
