Kubernetes features

If you didn’t have a chance to read our article on what Kubernetes is and how it is used, it probably makes sense to do so just to have a larger picture or so-called “helicopter view”. Here is the link for your convenience.

Kubernetes defined

Google’s name behind the Kubernetes brand certainly adds credibility. However, the 2017 decision to make it available to the general public free of charge has added more colors as to this date. 

Technically speaking, Kubernetes is a container management system that helps manage containerized apps in all kinds of environments, namely physical, virtual, and cloud. K8s is a highly flexible tool that delivers complex apps running on clusters. 

Kubernetes are also often referred to as a container orchestration tool to simplify the management of containers, making them more efficient and effective. This is usually achieved via simplifying the work of tech teams, replacing manual services deployment with automatization of many processes and deployment itself.  

It can be used on-premises or in the cloud. Everyday use cases of k8s include:

• Hybrid and multi-cloud.
• Creation of vendor-agnostic serverless platforms.
• Deployment of self-healing and scaling services.

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Infrastructure as a Code (IaC)

Undoubtedly, containers have become an essential component of today’s IT world, and industry experts even claim that they may take over the leading edge. As a result, more and more companies are switching to containers appreciating their prevailing advantages over traditional virtual servers/machines, significantly improving deployment and application development speeds. 

However, this has also created a challenge of managing those thousands of containers efficiently and effectively, which brought-in Kubernetes and Infrastructure as Code concepts. 

Technically speaking, Infrastructure as Code is the concept of managing infrastructures like data servers, storage, and networks using the code instead of operating them manually.

In a nutshell, machine-readable files are used to confirm the infrastructure, employing the entire infrastructure using the code. This allows for much easier deployment or redeployment of identical infrastructure where it might be needed, making the life of the DevOps team much more manageable and the results of their work quicker and more efficient.

The idea behind containerization

Automate action is not everything; daily routine does not low to avoid maintenance. Yet, it requires time and often a pause in the functioning of apps or devices. However, users would not accept any downtime, which is also why datacentres aim to have their uptime guarantee as high as possible, i.e., close to 100%. 

Even so, developers are forced to find methods and ways to perform necessary maintenance or updates without being forced to interrupt their services. 

Containers that are isolated environments have successfully provided the remedy. Those include everything the app needs to run smoothly. It also makes it pretty easy for a developer to reply and audit apps, providing for much greater efficiency. Undoubtedly, containerization has eventually become a well-deserved preferred approach in packaging, deploying, maintaining, and updating web-based apps.

Talking Kubernetes Let’s Arm Ourselves with Basics

The following terminology forms K8s fundamentals:

Cluster – a collection of hosts(physical or virtual servers) that assists you in aggregating their available resources. That includes RAM, CPU, memory, disks, and their hosting devices into a usable pool.

Master – is a collection of components that make up the control panel of Kubernetes. These components are used for all cluster decisions. It includes both scheduling and responding to cluster events.

Node – is a single host which is capable of running on a physical or virtual machine. A node should run allkube-proxy, minikube, and kubelet, which are considered to be part of the cluster.

The namespace is a logical cluster or environment. It is a widely used method which is used for scoping access or dividing a cluster.

Understanding the functionality and features that are available to you is necessary to get the most significant benefit from this tool.

Benefits and Advantages of Kubernetes

K8s popularity could not possibly be built on an empty space. Google developed it, which brought years of valuable industry experience to the table. However, it is worth summarizing the most apparent moments.

To begin with, K8s allow for control and automation of deployments and updates. This, in its turn, leads to saving money by optimizing infrastructural resources achievable via more efficient use of hardware. 

Moreover, Kubernetes permits its users to orchestrate containers on multiple hosts, solving many common problems derived from the proliferation of containers by organizing them in “pods .”This is followed by making it easy in terms of organization of service with those pods.

K8s can be considered the most prominent community among container orchestration tools. It allows scaling of resources and applications in real-time along with testing and autocorrection of applications. It creates a win-win situation for both developers and end-users. 

Kubernetes can run on and in quite diversified devices and environments. That is to mention bare metal, private and public clouds. Although, it adheres to the principles of immutable infrastructure.

K8s helps you avoid vendor lock issues as it can use any vendor-specific APIs or services. Containerization using Kubernetes allows package software to serve these goals. It will enable applications that need to be released and updated without any downtime.

Kubernetes allows you to ensure those containerized applications run where and when you want and helps you find resources and tools you want to work.

 Features of Kubernetes

Broadly speaking, K8s has quite a wide range of features. And it probably makes sense to divide them into general and more specific ones. 

As already mentioned, K8s automates various manual processes, saving a great deal of time and labor costs. For example, Kubernetes can control which server will host the container and the launching process. 

Kubernetes is able to manage more than one cluster at the same time, interacting with several groups of containers at a time. 

Kubernetes is multi-functional in such respect that it provides additional services, and not only the management of containers. K8s offers security, networking, and storage services, which is a relatively substantial side effect of the overall functionality.

Moreover, K8s is significant in terms of self-monitoring, which is illustrated by regular checks of the nodes and containers’ health. 

Scaling is another one to be mentioned. Kubernetes is quite unique as it can provide resource scaling virtually and horizontally, making the overall degree of integration relatively fast and easy. 

When it comes to storage, K8s employs principles of orchestration and customization, mounting and editing storage system in line with your project’s requirements. 

Kubernetes is not about backups but automatic rollouts and rollbacks. That practically means that should you lose something or anything goes wrong, K8s will automatically employ rollback for you. 

Kubernetes intelligence reaches even further so that it always knows where to place containers. This is achieved by calculating the so-called “best location” for them. Hence optimization is K8s’s second name. 

Finally, it is worth highlighting its universal nature in terms of being blue to run almost everywhere. Your workloads can accommodate or migrate between on-premises, hybrid, or public cloud infrastructure, providing a great deal of efficiency and flexibility.

Advanced K8s Features

Industry experts suggest that in case you want to dive deeper into the matter, the following list of the advanced functionality and functions should come in hand for you, so to build on the basics of K8s:

1. Sidecars

Sidecars are a feature that enables you to run an additional container within a pod to be used as a watcher or proxy. You use this extra container to direct data to be mounted and exposed to other containers in the pod. For example, sidecars could be used to handle logging or authentication for a primary container. Sidecars are helpful for allowing related processes within a pod to communicate without modifying the primary container source code

2. Helm Charts

Helm is a package manager for Kubernetes that you can use to streamline the installation and management of k8s applications. It uses charts composed of descriptions of the package and templates containing k8s manifest files. You use manifest files in k8s to create, modify, and delete resources.

Helm enables you to create and share reproducible builds of k8s applications. Helm charts allow you to deploy applications quickly and easily. There are many preconfigured charts available with their dependencies included.

3. Custom Controllers

Controllers are loops that regulate the state of your system or resources. With custom controllers, you can accomplish tasks that aren’t included with standard controllers. For example, you can dynamically reload application configurations. Custom controllers can be used with native or custom resource types. 

Using these controllers can be an easier way to manage deployments than toolchains. Controllers are a single piece of code, while toolchains require familiarity with several interfaces.

4. Custom Scheduling

K8s comes with a default scheduler for assigning newly created pods to nodes. If this scheduler doesn’t fit your needs or if you would like to run multiple schedulers, you can create a custom scheduler. For example, you could use custom scheduling to facilitate cloud bursting. Cloud bursting is when you move a workload to the cloud in order to meet higher performance or traffic demands.

Custom schedulers can be helpful if you have unique pods to handle separately from the others. You can set schedulers according to preference or requirement. Scheduling can rely on strict matching or inclusion and exclusion lists.

5. PodDisruptionBudget (PDB)

Header 3: 5. PodDisruptionBudget (PDB)

PDB is a feature that enables you to restrict the number of pods in a cluster that you can stop voluntarily. It helps ensure that a minimum number of pods stay active during tasks like maintenance, auto-scaling down, or upgrading. 

With PDB, you can prevent application availability or performance from affecting administrative tasks. A vital limit to keeping in mind with PDB is that it does not have an effect if a node fails, only when changes are done voluntarily.

6. Go Modules

Go modules are collections of Go packages you can use to manage your application dependencies. Dependencies are bits of code, libraries, or frameworks that your application depends on to run. Kubernetes supports Go modules from v1.15 on. 

Modules enable you to use multiple versions of the same dependency package or to use dependencies stored in different environments. You can use modules to ease code sharing between distributed teams and minimize the impact of changes in dependencies.

7. Taints and Tolerations

Taints and tolerations are a feature that enables you to direct nodes to “attract” or “repel” pods. Taints are assigned to nodes and specify that pods that do not tolerate the taint assigned should not be accepted. 

Tolerations are assigned to pods and signals to nodes with matching taints that pods can be accepted. This feature is helpful if you need to deploy an application on specific hardware or if you want to dedicate a set of nodes to particular users.

8. Cluster Federation

Cluster federation enables you to treat multiple clusters as a single logical cluster, managed through a single control plane. Federation allows clusters to run in different locations or environments to be more easily managed. You can use federation to make clusters highly available and resilient by enabling workloads to pass between clusters.

9. Health Checking

You can check the health of pods or applications in k8s by defining probes to be run by a kubelet agent. You can define readiness, liveness, and startup probes, as follows: 

• Readiness – determine if a container can receive requests. If it fails, the pod IP address is removed from any endpoints directing traffic to the pod. 
• Liveness – determine if a container needs to be restarted. Failure means the container is killed and restarted. 
• Startup – determine if an application within the container has started. In the case of failure, the container is killed and restarted.

You can customize probes with timeouts, retry attempts, minimum success or failure thresholds, and delayed runtimes.

10. Feature Gates

Feature gates are functionality in k8s that you can use to turn features on or off on a node, cluster, or platform level. This functionality enables you to safely test features without risking critical components or your production environment.

You can use gates to control alpha, beta, or stable (GA) features. Each feature gate controls only one feature. Alpha features default to off, and beta and GA features default to on.

Concluding note

Among numerous strengths of Kubernetes, it is worth highlighting K8s modularity and generality. Almost any application you might want to deploy is positive to accommodate Kubernetes. It doesn’t really matter what kind of adjustments or tuning you need to make to your system; these are within the scope and reach of K8s. 

It is vitally important to understand that IaC plays a very crucial role in Kubernetes. Proving a unique possibility to deploy Kubernetes clusters using the IaC on multi-cloud or the private cloud. Likewise, utilizing Kubernetes manifest files and helm charts, containerized microservices can be deployed on different Kubernetes clusters at an impressive speed, pushing the manual provisioning of Kubernetes clusters off the road of progress. Full automation is set to take place as well as diminish any worried about the infrastructure documentation. The future has arrived at our doorstep