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So let's now have a look at the Kubernetes cluster.

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What is that?

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Kubernetes cluster consists of nodes.

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Node is actually server either bare metal server or virtual server.

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And you could include multiple such servers into the Kubernetes cluster.

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And they could be located in different data centers in different parts of the world.

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But usually nodes which belong to the same Kubernetes cluster are located close to each other in order

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to perform all jobs more efficiently.

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Inside of the node, there are pods.

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Port is again the smallest possible unit in the Kubernetes.

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And inside of each port there are containers, usually single container per pod.

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And such boards are created on different nodes, and all of that is done automatically for you.

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Kubernetes does this job, but of course your job is to create such nodes and create cluster based on

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those nodes.

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Nodes will not automatically form cluster without your intervention, but after such initial configuration,

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everything will be automated and Kubernetes will automatically deploy both on different nodes.

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But how those nodes actually communicate with each other and how are they managed?

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In Kubernetes cluster there is master node and other nodes in the cluster are called worker nodes,

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and master node actually manages worker nodes and its master nodes job to distribute, for example,

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load across other worker nodes and all ports which are related to your applications are deployed on

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worker nodes.

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Master node runs only system ports, which are responsible for actual work of the Kubernetes cluster

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in general.

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We could also say that master node in the Kubernetes cluster is actually control plane and it does not

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run your client applications.