{"id":75017,"date":"2020-04-27T07:45:57","date_gmt":"2020-04-27T07:45:57","guid":{"rendered":"https:\/\/www.whizlabs.com\/blog\/?p=75017"},"modified":"2024-04-04T10:43:51","modified_gmt":"2024-04-04T05:13:51","slug":"kubernetes-certifications","status":"publish","type":"post","link":"https:\/\/www.whizlabs.com\/blog\/kubernetes-certifications\/","title":{"rendered":"A Guide to Kubernetes Certifications"},"content":{"rendered":"

One of the significant advancements in recent times is container technology. As an IT professional, if you have worked with Docker, then you must know about the role of Kubernetes. Kubernetes certifications<\/a>\u00a0can help you find new opportunities for your career in application development. Since the integration of all Docker<\/a> operations with Kubernetes in 2017, the latter has gained substantial popularity.\u00a0<\/span><\/p>\n

Kubernetes<\/a> is an open-source system for container orchestration, thereby helping users derive the maximum possible value from containers. It also helps in the automatic management of networks alongside the creation of logos and alerts as well as the deployment of container technology in IT operations. Kubernetes has been under the management of the Cloud Native Computing Foundation (CNCF)<\/a>, which takes care of the implementation and deployment of Kubernetes.\u00a0<\/span><\/p>\n

The CNCF is the governing authority for the two\u00a0Kubernetes certifications, which help in improving your knowledge regarding Kubernetes. The dominance of Kubernetes in the world of DevOps<\/a> is one of the reasons to choose to go for certifications in Kubernetes. The following discussion would reflect on the important details regarding certifications related to the Kubernetes platform.\u00a0<\/span><\/p>\n

Kubernetes is the new standard for deploying and managing applications on the cloud. The Kubernetes components and architecture might look overwhelming especially if you are a beginner.\u00a0 In this tutorial, we will see the simplified view of Kubernetes architecture and the components of Kubernetes.\u00a0<\/span><\/p>\n

What is Kubernetes?<\/h4>\n

Kubernetes is an open-source container orchestration platform that automates the processes involved in the deployment and management of applications.<\/span><\/p>\n

History of Kubernetes<\/h4>\n

Kubernetes was started by developers from Google as a way to orchestrate containers, later it was open-sourced. Google introduced an open-source version of Borg(a project started by Google) as Kubernetes in mid-2014. Kubernetes is now managed by Cloud Native Computing Foundation(CNCF).\u00a0<\/span><\/p>\n

What are Containers?<\/h4>\n

If the Kubernetes is a container orchestration tool, then what is the container? The container is a technology to package the application code along with its dependencies. Each container that we run is repeatable and it gives you the same behavior regardless of where we run the application.\u00a0<\/span><\/p>\n

Why to use Containers?<\/h4>\n

We can understand this better by comparing it to typical architecture. There will be a hardware infrastructure and the operating system installed on it. All the libraries and dependencies will run on the OS. Applications will share the same libraries and dependencies. That means the library versions will be the same for all the applications. For example, if we run Application A and Application B, the libraries will be compatible with Application A but not for Application B. Managing dependencies becomes more difficult in this situation.\u00a0<\/span><\/p>\n

To resolve this issue, the Virtual Machines concept came into the picture. Virtual machines use the software called hypervisors and give the functionalities of physical computers. Some of the Hypervisors are HyperV, VMWare, and VirtualBox. Virtual machines share the hardware and host Operating systems, on top of it, install the guest OS and run the dependencies.\u00a0<\/span><\/p>\n

The problem with Virtual Machines is the guest operating system. We need to maintain the host OS and the guest OS. Due to this reason, VMs are a bit slow to start. A significant amount of resources by VMs are utilized by guest OS so we need to over-provision the resources. To solve these issues, the containers came in.\u00a0<\/span><\/p>\n

Benefits of Containers<\/h4>\n

We don\u2019t have to install the guest OS for the containers. Containers utilize the same host OS and run as a separate process. Containers use the container runtime and some of the popular run times are Docker and Containers. All the applications and their dependencies will be independent of each other.<\/span><\/p>\n

Portability:<\/em> Whenever we run the containerized application, it will give the same behavior because the dependencies and applications are packages together.\u00a0<\/span><\/p>\n

Speed:<\/em> Containers can boot within a few seconds whereas the VMs may take a minute or two.<\/span><\/p>\n

Scalability:<\/em> Since the containers can start within seconds, spinning up containers is easy. We can have multiple containers scaling up and down independently.<\/span><\/p>\n

Lightweight:<\/em> Containers do not have to run any guest OS so it\u2019s very light compared to VMs. With fewer computing resources, containers can run like an application by utilizing the host Operating system.\u00a0<\/span><\/p>\n

Containers and Kubernetes<\/h4>\n

We have discussed the benefits of containers. Containers are good for microservices. Now the issue is how to manage multiple containers and enable communication between the containers? The container orchestration is a solution!<\/span><\/p>\n

The concept of Kubernetes is that multiple servers (called nodes) form a cluster. Kubernetes orchestrates containers within these servers. Applications run within the containers. If we need to scale the cluster, we can simply add more servers(nodes) to the cluster.\u00a0<\/span><\/p>\n

Kubernetes consists of master nodes (control plane) that orchestrate the containers and worker nodes where the containers will be running.\u00a0<\/span><\/p>\n

Kubernetes Objects<\/h4>\n

Let us now understand the Kubernetes objects and commands terminologies used in Kubernetes such as clusters, nodes, pods, deployments, replica sets, replication controller, stateful sets, Persistent volume, daemon sets, services, Ingress etc<\/span><\/p>\n

Cluster<\/h4>\n

A Kubernetes cluster is a set of nodes that runs the application. In Kubernetes, we need to think about the cluster as a whole regardless of the individual machines. Nodes together form a powerful machine as a cluster. If any nodes are added to the cluster or removed from the cluster, the cluster will shift the work as necessary.\u00a0<\/span><\/p>\n

Nodes<\/h4>\n

A Node is the smallest hardware component in the Kubernetes architecture. A <\/span>Node<\/span><\/a> can either be a physical machine on-premise or a virtual machine hosted on the cloud-like Amazon Web Services (AWS). Regardless of the characteristics of individual machines, we can view each machine as a set of RAM and CPU that can be utilized.\u00a0<\/span><\/p>\n

Pods<\/h4>\n

Pods are the smallest unit or fundamental building block of Kubernetes architecture. Kubernetes run containers in the pods. Usually, each pod will have one container but it can be more than one also. You create a POD to run an application.\u00a0<\/span><\/p>\n

Persistent Volume<\/h4>\n

Persistent volumes are the storage resources for the Kubernetes. It can either be provisioned manually or dynamically by storage classes. Persistent volume disks can be mounted to the containers.<\/span><\/p>\n

Deployments<\/h4>\n

Deployments are used to deploy Kubernetes pods. It\u2019s possible to roll out and roll back deployments. The deployment method can be used for running a stateless application that connects to a backend database and does not persist data to the disk. This is the most commonly used method to deploy pods.\u00a0<\/span><\/p>\n

Ingress<\/h4>\n

Ingress is a Kubernetes object that allows the HTTP and HTTPS traffic from outside the cluster to the services within the cluster. We can create a collection of rules to configure which traffic reaches which service in the cluster. An Ingress controller is used to achieve this.<\/span><\/p>\n

Ingress Controller<\/h4>\n

An Ingress Controller is an application running on the cluster and configures an HTTP load balancer. The ingress controller is mandatory for the ingress resource to run. There\u2019s no limit on how many ingress controllers are running in a cluster.\u00a0<\/span><\/p>\n

ClusterIP Service<\/h4>\n

ClusterIP is the default type of service that is used to expose a service on an IP address internal to the cluster. Pods running inside the cluster can call other services using ServiceName: Port.\u00a0<\/span><\/p>\n

NodePort Service<\/h4>\n

NodePort service exposes the pod to the nodes using a static port and can be seen from any of the nodes inside the cluster. The Node Port range is 30000 – 32767. If we don\u2019t provide a port number, it will automatically pick the available port.\u00a0<\/span><\/p>\n

LoadBalancer Service<\/h4>\n

Let\u2019s assume that we have one master and four worker nodes, and the nodes are named master, node1, node2, node3, and node4. Considering that we have an Nginx pod running on port 80, we want to expose it to the internet. A LoadBalancer service creates a NodePort from the NodePort range and creates a LoadBalancer which will run on port 80 as frontend, master:30000, node1:30000, node2:30000, node3:30000, and node4:30000 as backend. The LoadBalancer service is the most commonly used method to expose the frontend pod to the internet.<\/span><\/p>\n

Daemon Sets<\/h4>\n

A Daemon set is a Kubernetes object that ensures that the given pod in the set runs on all the available nodes in a cluster. When we add or remove nodes to the cluster, the daemon set adds or removes the pods in those nodes.<\/span><\/p>\n

Stateful Sets<\/h4>\n

A Statefulset ensures that the pod and its volumes are unique. The storage that was mounted as volume to the pod gets attached to the same if it\u2019s destroyed.\u00a0<\/span><\/p>\n

\"Kubernetes<\/a><\/p><\/blockquote>\n

Benefits of Kubernetes Certifications<\/span><\/h2>\n

The first thing that you should note about Kubernetes certifications is its significance. Candidates should know that Kubernetes is now a very crucial technology in the IT industry. So, it is essential to understand the benefits of Kubernetes certifications before you start pursuing preparations. You should know what your hard work is worth before you invest it. Here are the notable benefits of a certification in Kubernetes.<\/span><\/p>\n