What is Kubernetes?
In more and more IT areas, decentralization is proving to be the superior form of organization. This is also the case in the field of Linux developers, where independently acting containers have now become a fixed standard. However, this can quickly lead to chaos and mismanagement in larger applications that combine a large number of containers. The open-source Kubernetes software provides several solutions to this very problem.
What Kubernetes is
Kubernetes is an open-source platform that, simply put, is designed to simplify and automate the use of Linux containers. Containers have also become popular for Linux applications due to their significantly reduced
development time compared to traditional pipelines and safer and more effective everyday use.
However, if you have to manage an extensive Linux structure consisting of countless containers, this can quickly become an organizational nightmare. After all, all processes must be planned and executed individually for each container. Moreover, this makes it almost impossible to effectively scale one's own structure. Kubernetes is the answer to these problems.
This is because the Kubernetes application once automates countless commands and processes that can now be executed for all containers, or for a specific group of containers, simultaneously. In addition, pods can be used to create different levels of organization that further simplify the operation of one's Linux platform. In addition, Kubernetes can also be used to integrate containers from the various hosts into a single cloud.
Kubernetes: The most important technical terms
The Kubernetes system uses some technical terms that you won't find anywhere else. Therefore, we will first take a look at the terminology here:
- Cluster: when Kubernetes is successfully applied, it is referred to as a cluster. All other parts of the system are organized within this cluster.
- Pod: The smallest unit in Kubernetes. A pod is a container made up of one or more containers, all implemented through a single node. Thus, the containers within a pod not only share the same IP address, IPC, and hostname, but are also managed together.
- Nodes: The computing machines execute the assigned tasks by accessing the containers.
- Service: The service proxies ensure that service requests within the system automatically land at the correct pod.
- Control Plane: As the name suggests, this is the control unit of the system. This is where the user assigns or requests all tasks.
- Replication Controller: The Replication Controller ensures that the desired number of identical pods is always active on the cluster.
- Kubelet: The Kubelet service can be thought of as a kind of checkpoint. This is deployed at the nodes through which the pods are deployed and ensures that all containers are functioning properly.
Why is Kubernetes so popular and so important? In a nutshell, Kubernetes makes it possible to manage even comprehensive systems made up of individual containers in a straightforward and efficient manner. In simple terms, then, Kubernetes is an organizational aid that allows large container deployments to be arranged in tiers and, for the most part, managed automatically.
The most important feature of Kubernetes is that it can be used to combine multiple containers into a single pod. This not only makes it much easier for the user to plan workloads, but also to always provide the individual containers with sufficient networking and storage. This also makes it possible to scale countless containers within a single system.
In addition, thanks to the nodes and system proxies, the user no longer has to assign tasks manually. As an administrator, one only enters the desired task, Kubernetes then assigns this independently, monitors the utilization of the nodes and the presence of sufficient resources.
How Kubernetes works
A successfully implemented Kubernetes system is called a cluster. The heart of this cluster is the Control Plane. This is where all tasks are entered or requested. The Control Plane then forwards these instructions, with the system automatically deciding which node, i.e. which computing machine, is best suited for the application and how many resources are required for it.
Each node is a standalone Linux environment and can be either a physical machine, i.e., a computer, or a virtual machine, i.e., a cloud. The nodes, in turn, run the pods, which group one or more containers together. After the control panel assigns a task to a node, the node executes the task by using the containers.
This does not change the general management or use of the containers. However, users now no longer have to micromanage each container individually, but can simply specify in the cluster how and with which resources the individual containers should work. Everything else is then executed automatically.
Here's what to keep in mind about Kubernetes
Kubernetes is an open source platform, so it can basically be used free of charge. However, this also means that, unlike other online services, no support structure is provided by the provider. So if you want to use Kubernetes for your own systems, careful planning, implementation and maintenance is extremely important. After all, if an application does not work, there is no one to turn to.