Kubernetes

K8s Components

Node and Pod

Node

• A Node is the smallest compute unit in Kubernetes; it can be a virtual machine EC2 or a physical machine located in a data center.
• Each node has CPU and RAM, storage, and its resources are used in the cluster.
• Static IP address

Containers

• Program will be packed into container and it is the instance of program.
• Multiple programs can be added into a single container, but the best practice for manage is 1 container just run a single process.
• Separation of concern is principle for separating a computer program into distinct sections and the resone why have many small containers than one large one.

Pod

• “Pods are the smallest deployable units of computing that you can create and manage in Kubernetes.”
• Is the higher level of container. Each pod has one or more containers running inside it.
• Pods are scaled up and down regularly, all containers in a pod must scale together, regardless of their individual needs. We must to set one container per pod to prevent wasted resources and an expensive bill.
• Just use multiple container running in a pod when apply side-car patterns.

Services