Kubernetes in a DevOps World

Introduction to Kubernetes

If you are working in cloud-native environments and managing containerized applications you must have heard of Kubernetes also known as K8´s. It is an open-source container-orchestration tool that was mainly developed by the Google team to manage their containerized workflows. Google open-sourced it in 2014 and after that, they worked with The Linux Foundation and released Kubernetes 1.0 on July 21,2015. Now Kubernetes is totally an open-source community with engineers working for top tech companies such as Google, RedHat, VMware, etc.

Many companies are now using Kubernetes to manage their container workloads and infrastructure at a large scale. Some are facing trouble trying to convert their workload into microservices or finding a good consultant so that they can containerize their workloads and run them as microservices in a scalable and highly-available environment. When it comes to Kubernetes consulting you should always find the best consultant as Kubernetes is a very complex tool and not all engineers know it to the depth StackOverdrive´s engineers do. If the infrastructure is not configured correctly according to the workload it can lead to many overpaid bills and so much more. So today we are going to talk about some main components of Kubernetes and talk about the advantages and disadvantages of using K8´s in your company based on different workloads so that you can understand how it works and which types of workflows can use its advantages.

Kubernetes Architecture

As Kubernetes is a powerful and complex framework, we will give you a basic understanding of the Kubernetes Architecture and its main components.

Kubernetes consists of two types of nodes, Master node and a Slave node. A node is a worker machine either physical or virtual in which Kubernetes is installed and containers are launched as pods by Kubernetes. Multiple nodes are combined to form a highly-available and scalable Kubernetes cluster so even if one node gets down your website will still be accessible by other working nodes.

Master Node

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The Master Node is the heart of each of each Kubernetes cluster. It is used to control your clusters, check the desired and current state of the clusters and contains all the configuration data of your cluster. Its main components are the API Server, Controller Manager, ETCD, and Scheduler. Let´s talk in detail about these components and their use cases.

1. Kube API-Server: Kube-apiserver is the component of the master node which exposes the Kubernetes API that takes a request, validates it and process that request after the validation. You can access the Kubernetes API from kubectl CLI, REST calls, and some other tools.
2. Kube-Scheduler: Kube scheduler´s job is to check for the newly deployed pod manifests and assign them to the node according to their given requirement such as CPU & Persistent volumes (PV).
3. ETCD: ETCD is a key-value store that is highly available and can exist on multiple master nodes used by Kubernetes to store the configurations and state of the whole cluster. It doesn´t contain any faults in it and you should take weekly backups of your etcd.
4. Kube Controller-Manager: The Kube controller manager is a control panel that consists of different controllers with different functionality compiled together. It compares the current state of the cluster with the desired state and makes changes if required. Some of the controllers are Node Controller, Replication Controller, Endpoint Controller, and a few more.

Slave Node:

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Multiple slave nodes are combined to make a cluster and every slave node must contain these components: Container Runtime, Kubelet, and Kube-proxy.

1. Container Runtime: Container Runtime Engine is responsible for executing containers. Every worker node comes with a container runtime engine with the most famous one being docker. Now Kubernetes also supports other container runtimes such as containerd, rktlet, etc.
2. Kubelet: Kubelet is a small service in which an agent is present on every node. Its responsibility is to make sure that each pod is running on the specified node with proper configurations, It completes the tasks provided by Kubernetes Master Node.
3. Kube-Proxy: Kube proxy is a proxy service that is present on every worker node. It is responsible for communication between the pods and the users that want to access our site. It manages all the networking work between the nodes.

Benefits of using Kubernetes

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Kubernetes is a very useful tool and if configured correctly according to your workloads you can get so much from it which is why many Big Companies are using or moving toward using it for their workloads. It helps companies manage their enterprise-level application on a large scale with highly-available infrastructure and zero downtime. As it´s a very complex tool if you are not fully aware of it you should always leverage a Kubernetes Consulting to build and maintain your Kubernetes Infrastructure so that a can best make us of its advantages. Some main advantages below:

1. Fasten DevOps process
2. Easy Cloud Migration
3. Handling Multi-Cloud Environment
4. Cost Saving
5. Fast Scale-In and Scale-Out
6. Decralative Infrastructure
7. Rapid Disaster Recovery