|VMware or Virtualization Terminology||Description|
|VMware vCenter||vCenter is a server that is installed on either Linux or Windows and provides central management of VMs and ESXi hosts.|
|VMware vSphere or ESXi||ESXi is a component of vSphere. It is a hypervisor that defines processor, memory, storage, and networking resources into multiple VMs that run applications.
ESXi is installed (bare metal install) directly on the server hardware, inserting a virtualization layer between the hardware and the operating system. ESXi partitions a physical server (pnode) into multiple secure VMs (vnodes) that run on the same physical server. Each VM represents a complete system, with processors, memory, networking, storage, and BIOS so that the operating system and applications can be installed and run in the VM without modification. VMs are also completely isolated from each other by the virtualization layer to prevent a crash or configuration error in one VM from affecting the others.
|vCPU||For each licensed physical core you purchase, you get two virtual cores.
A virtual CPU corresponds to one hyperthreaded core. Vantage on VMware requires that hyperthreading be enabled.
|vSphere Virtual Switch||The vSphere virtual switch lets you set up VM access switching from a centralized interface so you can provision, administer, and monitor virtual networking across multiple hosts and clusters.|
|SQL Engine Node||An SQL Engine node, also known as a Teradata node, requires three pieces of software: a Trusted Parallel Application (TPA), Parallel Database Extensions (PDE), and an operating system. Vantage is classified as a TPA. SQL Engine nodes can be either physical or virtual. An SQL Engine node is deployed as a Teradata appliance on VMware.|
|Physical Node (pnode)||A pnode is a physical server running in a data center, manufactured by any vendor (OEM) fully supported by VMware. All pnodes must be configured with identical CPU, memory, network, and storage. All pnodes must be connected identically to allow vnode TPA instances to be deployed to any ESXi host. One pnode corresponds to a single ESXi host or to the actual hardware, such as to one Dell R720, R730, and so on. During deployment, CPUs and memory are checked to ensure they are the same on all pnodes containing vnode TPA instances.|
|Virtual Node (vnode)||A vnode is a virtual node running on a pnode in a data center. pnodes can have one to four vnodes, defined through the ESXi hypervisor. A single vnode corresponds to a single VM that runs Teradata software.|