The Kubernetes clusters in certification exams often run on multiple nodes. Usually on at least one master node and one worker node. With our multi-node Kubernetes playground, you can practice in a similar environment. And it only takes seconds to get access to a multi-node Kubernetes cluster!
You can test theories, experiment, and learn. Run kubectl commands to get some experience before the exam. Everything is easily accessible through your web browser. No need to install anything!
If required, you can also SSH into each node, in case you want to practice your troubleshooting skills.
A Kubernetes cluster is made out of multiple interconnected nodes (basically servers). This makes it easy to scale up when demand is high. We just add more nodes, and the cluster becomes more powerful and able to handle more traffic. When demand is lower, we scale down by removing nodes. This makes Kubernetes flexible, easy to adjust. Furthermore, it also makes it more resilient. If one node experiences problems, another healthy one can quickly take its place. This makes the cluster highly available; it keeps working, even if some nodes malfunction.
This playground will provide you with two nodes. One is the master node, and the other is the worker node. You will learn how to navigate between these two. As mentioned, you can SSH into any node if you want to test your troubleshooting skills.
If you need to, you can also modify your master node to allow pods to be scheduled on it. This way, you can experiment with pod scheduling, node affinity, taints, tolerations, and so on.
Container Network Interfaces or CNI enables networking capabilities within your Kubernetes cluster and internal components. It allows communication between nodes, pods, and also services. It is one of the primary components that is required in order to set up a Kubernetes cluster. One of the widely-used CNI available is Flannel. It is a lightweight and quite a basic network layer solely designed for Kubernetes. This is the CNI for those who want a simple and quick networking solution for their Kubernetes clusters and do not need any other advanced features like network policies to be implemented.
If you want to try a different Container Network Interface, you can experiment in our other playground preconfigured with the Weave CNI.