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What is the smallest unit in the Kubernetes world?

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In Docker world?

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Container is smallest unit.

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In Kubernetes, port is the smallest possible unit.

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And containers are created inside of the port.

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So port anatomy is following inside of the port.

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There could be containers, either one or even several containers.

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Also, there are shared volumes and shared network resources.

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For example, a shared IP address.

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This means that all containers inside of the same port share volumes and share IP address.

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And you must keep that in mind if you want to create multiple containers inside of the same port.

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Most common scenario, of course, is to have just a single container per port.

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But sometimes when containers have to be tightened together and they heavily depend on each other and

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they could exist in the same namespace, it is possible to create several containers in the same port.

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But again, single container per port is the most common use case.

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Also, please keep in mind that each port must be located on the same server.

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It is not possible to spread containers from one port across different servers in the Kubernetes cluster.

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One port.

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One server.