Understanding EMC VPLEX array and array virtualization

EMC VPLEX arrays support array virtualization. Essentially, it’s a type of SAN/storage implementation where one or more back-end arrays (for example, Symmetrix) can provide storage to VPLEX or any other array (for example, EMC Celerra, a NAS device).

The storage used in a VPLEX cluster can be physical or virtual. Let’s talk about “virtualized storage” for VPLEX and understand the “storage components hierarchy” in a typical VPLEX array.

We will begin with Storage Volumes (SVs). A Storage Volume is essentially the storage provided by the back-end array. On top of a Storage Volume, you can create one or more Extents.

Using these Extents, you create Devices. Here again, you can form a Device using multiple Extents, or you can establish one-to-one relationship between an Extent and a Device. And lastly, Virtual Volumes (VV) are created from these Devices.

A VV can be created using a normal Device or a Distributed Device.

If you have used a normal Device to create these virtual volumes, they are simply referred as Virtual Volumes. On the other hand, if you have used a Distributed Device for the creation of Virtual Volumes, such Virtual Volumes are referred to as Distributed Virtual Volumes.