vSphere IaaS control plane Terminology

You must understand the basic terminology in this chapter to be able use the vSphere IaaS control plane automation APIs effectively.

vSphere IaaS control plane Basic Terms

Term	Description
Supervisor	A vSphere cluster that has the vSphere IaaS control plane enabled.
Tanzu Kubernetes cluster	An upstream Kubernetes cluster provisioned and managed by using the VMware Tanzu™ Kubernetes Grid™. A Tanzu Kubernetes resides in a vSphere Namespace. You can deploy workloads and services to such clusters in the same way as you do with standard Supervisor.
vSphere Namespace	A namespace that is created within a Supervisor. Each namespace sets the resource boundaries for CPU, memory, storage, and also the number of Kubernetes objects that can run within the namespace. After a namespace is configured, you can run Kubernetes workloads within the namespace.
vSphere Pod	A virtual machine with a small footprint that runs one or more Linux containers. A vSphere Pod is equivalent to a Kubernetes pod. vSphere Pods are compatible with the Open Container Initiative (OCI) and can run OCI compatible containers regardless the operating system.
Spherelet	A spherelet is an implementation of the kubelet functionality ported natively on each host in the Supervisor.
Kubernetes Workload	Workloads are applications that are deployed in one of the following ways: As containers running inside vSphere Pods. Workloads provisioned through the VM service. Tanzu Kubernetes Gridclusters deployed by using the Tanzu Kubernetes Grid. Applications running inside the Tanzu Kubernetes Grid clusters.
Supervisor control plane	vSphere IaaS control plane creates a Kubernetes control plane directly on the hypervisor layer. The control plane manages the worker nodes and the vSphere Pods in the Supervisor.
Supervisor worker nodes	ESXi hosts that are part of a Supervisor are considered as worker nodes. You run your Kubernetes workloads on the worker nodes.
Container Runtime Executive (CRX)	CRX is an isolated Linux execution environment similar to a VM that works together with ESXi.
VM Service	The VM Service functionality allows DevOps engineers to deploy and manage virtual machines in their Kubernetes environment through standard Kubernetes APIs. vSphere administrators are responsible for providing VM Classes and VM Images for the DevOps engineers to choose from, as well as managing resource allocations to self-service provisioned VMs.
Self-Service Namespace	vSphere administrators can activate the Self-Service Namespace service on a Supervisor and create namespace templates for DevOps engineers to create a vSphere Namespace themselves.
vSphere Zones	vSphere Zones provide high availability against clusters-level failures to workloads deployed on vSphere IaaS control plane. You can configure a three-zone Supervisor mapped to three vSphere clusters or a one-zone Supervisor mapped to a single vSphere cluster. In a single cluster deployment, the high availability is provided by vSphere HA and is only on a host level.