Virtual Volumes – VVOLS
vSphere Virtual Volumes is composed by two key implementations:
Flexible consumption at the logical level
vSphere Virtual Volumes virtualizes SAN and NAS devices by abstracting physical hardware resources into logical pools of capacity (called Virtual Datastore) that can be more flexibly consumed and configured to span on or more storage arrays. The Virtual Datastore defines capacity boundaries, access logic, and exposes a set of data services accessible to the VMs provisioned in the pool. Virtual Datastores are purely logical constructs that can be configured on the fly, when needed, without disruption and don’t require to be formatted with a file system.
Finer control at the VM level
vSphere Virtual Volumes defines a new virtual disk container (Virtual Volume) that is independent of the underlying physical storage representation (LUN, file system, object, etc.). In other terms, with Virtual Volumes the virtual disk becomes the primary unit of data management at the array level. This turns the Virtual Datastore into a VM-centric pool of capacity. It becomes possible to execute storage operations with VM granularity and to provision native array-based data services to individual VMs. This allows admins to provide the right storage service levels to each individual VM.
To enable efficient storage operations at scale, even when managing thousands of VMs, Virtual Volumes uses vSphere Storage Policy-Based Management (SPBM). SPBM is the implementation of the policy-driven control plane in the VMware SDS model.
Efficient operations though automation
SPBM allows capturing storage service levels requirements (capacity, performance, availability, etc.) in the form of logical templates (policies) to which VMs are associated. SPBM automates VM placement by identifying available datastores that meet policy requirements and coupled with Virtual Volumes, it dynamically instantiates necessary data services. Through policy enforcement, SPBM also automates service level monitoring and compliance throughout the lifecycle of the VM.