Running a multi-user cluster
In this section, we will look briefly at the option to use a single cluster to host systems for multiple users or multiple user communities (which is also known as multi-tenancy). The idea is that those users are totally isolated and may not even be aware that they share the cluster with other users. Each user community will have its own resources, and there will be no communication between them (except maybe through public endpoints). The Kubernetes namespace concept is the ultimate expression of this idea.
The case for a multi-user cluster
Why should you run a single cluster for multiple isolated users or deployments? Isn't it simpler to just have a dedicated cluster for each user? There are two main reasons: cost and operational complexity. If you have many relatively small deployments and you want to create a dedicated cluster for each one, then you'll have a separate master node and possibly a three-node etcd cluster for each one...
