What is the smallest unit in the Kubernetes world?
In Docker world?
Container is smallest unit.
In Kubernetes, port is the smallest possible unit.
And containers are created inside of the port.
So port anatomy is following inside of the port.
There could be containers, either one or even several containers.
Also, there are shared volumes and shared network resources.
For example, a shared IP address.
This means that all containers inside of the same port share volumes and share IP address.
And you must keep that in mind if you want to create multiple containers inside of the same port.
Most common scenario, of course, is to have just a single container per port.
But sometimes when containers have to be tightened together and they heavily depend on each other and
they could exist in the same namespace, it is possible to create several containers in the same port.
But again, single container per port is the most common use case.
Also, please keep in mind that each port must be located on the same server.
It is not possible to spread containers from one port across different servers in the Kubernetes cluster.
One port.
One server.