In this article, we will be sharing some brief information on Docker Kubernetes Service. This information can help you grasp the essentials of Docker Kubernetes Service; which might come in handy when working on real projects.
Containers have long been available but they went mainstream only after Docker Inc popularized them. The firm marketed them in the right manner which paved the way for their widespread adoption. Container orchestration engines prevalent nowadays owe a lot to Docker Inc for making the use of Linux containers acceptable.
But what’s Kubernetes have to do with all of this? Well, it does! And that’s because Kubernetes is also a container orchestration engine and probably the most sophisticated one out of the lot.
That’s because Google developed it after it had accumulated loads of expertise on how to manage an infrastructure that was characterized by billions of containers. This system stripped down containerization to requiring only the most efficient set of resources. Thus, eliminating most of the unnecessary add-ons that were cumbersome to manage.
Now Kubernetes will also be available to Docker Inc users along with Docker Swarm. This will give users an unprecedented advantage in running containers on the world’s best engines.
Kubernetes – What Makes It Better Than The Rest?
Whether you want to manage, scale or deploy any of your applications that run via container-based systems. Kubernetes automates everything involved.
Kubernetes runs on open source as well. So if you have a team of highly experienced DevOps personnel, you can incorporate it on your own. If you don’t want to go through the hassle of doing that. You can use it as a ready-made package being currently offered by Docker Inc through the Docker Enterprise Edition.
Previously, you had no means to cluster groups of hosts that run your containers into a singular whole, making management difficult. But Kubernetes not just allows you to do that. But it also helps you manage them from its base, irrespective of where they are located.
Whether you run your container hosts on the cloud or in-house or work through a mix of both, Kubernetes extends its functionality by supporting all of them.
Kubernetes is an advanced version of Borg, the container engine that Google runs internally. Borg has the capacity to successfully run an environment that exceeds 2 billion containers every 7 days.
Google was one of the firms in the world to start working with containers and their unique needs led to the development of Kubernetes, a system with every single quality required to run the containerized application.
Under Kubernetes, everything gets automated. From monitoring the health of your system to rollouts to pullbacks. It can even prevent unsuitable rollouts from getting to your system in the first place.
It’s also incredibly scalable, so you don’t need to waste extra resources when you don’t have enough requirements. Cluster management is also one of its most prominent attributes, providing room for replication of the system versions easily whenever called upon.
Important Features that Run the Mechanism
Inside Docker Kubernetes Service
As much as the ease it offers, Kubernetes works through an incredibly complex, underlying mechanism consisting of the following parts:
– Desired State
One of the most challenging aspects in the containerization arena before Kubernetes was controlling the state of execution of containers. Previously available orchestration engines didn’t allow you to do that inside a pod. But Kubernetes not just allows you to define a state, it restarts the pod on it if the container fails due to any particular reason.
Every cluster running under Kubernetes has to always follow this desired state as mandated by the system. The Kubernetes Control Plane can be used to control these desired states via a special feature called Kubernetes Master.
– The Control Plane
This is the feature that makes it possible to orchestrate the “Desired State” command under Kubernetes. It runs automatically and is there to ensure that your cluster state always matches the desired state, irrespective of what happens elsewhere. The Control Plane handles many complex tasks like re-executing containers, managing replica scalability, etc.
The recording of the object state of clusters is done on a continuous basis by the Control Plane and if at some time, it notices that a cluster is not working under the desired state, it steps into re-augment it and ensures that it comes back to the desired state.
– Kubernetes Master
This is a sub-function of the Control Plane which works along the same line of maintaining the desired state. It is run via a command named “Kubect1”. The cluster’s Kubernetes Master can be communicated with by using this very command, with the API acting as a mediator between these two ends.
Every node present in your cluster gets its control, direction, and coordination signals from this feature based on three different processes.
- Kube –apiserver
- Kube-controller-manager
- Kube-scheduler
– Kubernetes Node
These are the components that run the entire workload of all the clusters. They do all the work and can consist of several different machines including but not limited to cloud servers, physical servers, virtual machines, etc.
The Kubernetes Node are given commands by the Kubernetes Master and it’s through this command that the node “Knows” its desired state and the actions that are needed to remain on it.
Kubelet and Kuber-proxy are the two main processes run in these nodes.
Docker Kubernetes Service – Wrapping Things Up
The Docker Swarm Engine was good enough to run Containerization but since the advent of Kubernetes, it has taken a backseat. Kubernetes allows for more automation and ease of handling than any other containerization engine out there and is capable of managing the most complex of systems of any scale.
Many of the top cloud vendors out there are now offering their own managed Kubernetes services. Google and AWS are among the most prominent ones among them with products like Google Kubernetes Engine. You can integrate Kubernetes with them or run it on your own physical cloud platforms, the choice is totally yours.
The only turn-off here is that Kubernetes has still not been deployed on many different environments making it a bit un-tested, however, given that the underlying mechanisms have proved to be of great utility till now, the field of DevOps remains optimistic about the challenges that lie ahead for Kubernetes.
This is just a very basic introduction to the world of Kubernetes and if you want to dive deep and really know more, we’ve got some exciting resources that you might find of incredible assistance.