Kubernetes (pronounced koh-bert-net-says) is the go-to container orchestration platform that helps IT and DevOps teams simplify container management. Whether you’re working with cloud environments, physical machines, or bare metal servers, kubernetes can help you optimize hardware resources and automate deployment, scaling, monitoring, load balancing, and self-healing—all while reducing downtime and freeing up IT staff to focus on more strategic projects.
The key to kubernetes is that it’s all about abstraction. The platform manages applications across a group of physical or virtual servers called a cluster, which is made up of nodes—also known as worker machines—that can be physically located anywhere in the world. A single master node acts as the cluster’s control plane, which is responsible for managing the cluster’s state and deploying containers on it.
Each application in a kubernetes cluster is known as a pod. It consists of one or more containers that are guaranteed to be co-located on the same host machine and can share resources, and is controlled by an agent that runs on each node—called a kubelet. A kubelet automatically restarts containers that fail or don’t respond to a user-defined health check, and is responsible for routing traffic to services with the right IP addresses. A kubelet can be configured in a variety of ways, such as using YAML or JSON to describe the desired state of the container, and allowing a specific set of API requests to be executed on it.
A service in kubernetes is a type of pod that is exposed to the outside world via a DNS name, which is translated into the machine-readable IP address it needs to serve incoming requests. Each service can have multiple ports opened and accessed from different nodes in the cluster.