VMware
Virtual Volumes (VVols) - vSphere 6.0
Virtual
Volumes (VVols) is one the new
feature addition with vSphere 6.0. Virtual volumes are encapsulations of
virtual machine files, virtual disks, and their derivatives. Virtual volumes
are stored natively inside a storage system that is connected through Ethernet
or SAN. They are exported as objects by a compliant storage system and are
managed entirely by hardware on the storage side. Typically, a unique GUID
identifies a virtual volume.
Virtual volumes are not
preprovisioned,
but created automatically when you perform virtual machine management
operations. These operations include a VM creation, cloning, and snapshotting.
ESXi and vCenter Server associate one or more virtual volumes to a virtual
machine.
Currently all
storage is LUN-centric or volume-centric, especially when it comes to
snapshots, clones and replication. VVols makes it storage VM-centric. With VVols,
most of the data operations can be offloaded to the storage arrays. VVols goes much
further and makes storage arrays aware of individual VMDK files.Virtual volumes
encapsulate virtual disks and other virtual machine files as natively stored
the files on the storage system.
Note:
For every VM a single VVol is created to replace the VM directory in today’s
system.
·
1
config VVol represents a small directory that contains metadata files for
a virtual machine. The files include a .vmx file, descriptor files for virtual
disks, log files, and so forth.
·
1
VVol for every virtual disk (.VMDK)
·
1
VVol for swap, if needed
·
1
VVol per disk snapshot and 1 per memory snapshot
Additional virtual
volumes can be created for other virtual machine components and virtual disk
derivatives, such as clones, snapshots, and replicas.
Components
of VMware Virtual Volumes (VVols):
There are 3
important objects in particular related to Virtual Volumes(VVols) are the
storage provider, the protocol endpoint and the storage container. Let’s
discuss about each of the 3 items:
Storage
Providers:
·
A
VVols storage provider, also called a VASA provider.
Storage provider is implemented through VMware APIs for Storage Awareness
(VASA) and is used to manage all aspects of VVols storage.
·
Storage
provider delivers information from the
underlying storage,so that storage container
capabilities can appear in vCenter Server and the vSphere Web Client.
·
Vendors
are responsible for supplying storage providers that can integrate with vSphere
and provide support to VVols.
Storage
Container:
·
VVols
uses a storage container, which is a pool of raw storage capacity
or an aggregation of storage capabilities that a storage system can provide to
virtual volumes.
·
The
storage container logically groups
virtual volumes based on management and administrative needs.
For example, the storage container can contain all virtual volumes created for
a tenant in a multitenant deployment, or a department in an enterprise
deployment. Each storage container serves as a virtual volume store and virtual
volumes are allocated out of the storage container capacity.
·
Storage
administrator on the storage side defines
storage containers. The number of storage containers and their
capacity depend on a vendor-specific implementation, but at least one container
for each storage system is required.
Protocol
EndPoint (PE):
·
Although
storage systems manage all aspects of virtual volumes, ESXi hosts have no
direct access to virtual volumes on the storage side. Instead, ESXi hosts
use a logical I/O proxy, called the protocol endpoint,
to communicate with virtual volumes and virtual disk files that virtual volumes encapsulate.
·
ESXi
uses protocol endpoints to establish a data path on demand from virtual machines to
their respective virtual volumes.
·
Each
virtual volume is bound to a specific protocol endpoint. When a virtual machine
on the host performs an I/O operation, the protocol endpoint directs the
I/O to the appropriate virtual volume. Typically, a storage system
requires a very small number of protocol endpoints. A single protocol endpoint
can connect to hundreds or thousands of virtual volumes.
VVols
Datastore:
·
A
VVols datastore represents a storage container in vCenter Server and the
vSphere Web Client.
·
After
vCenter Server discovers storage containers exported by storage systems, you
must mount them to be able to use them. You use the datastore creation wizard in the vSphere Web
Client to map a storage container to a VVols datastore.
·
The
VVols datastore that you create corresponds directly
to the specific storage container and becomes the container’s
representation in vCenter Server and the vSphere Web Client.
·
From
a vSphere administrator prospective, the VVols datastore is similar to any
other datastore and is used to hold virtual machines. Like other datastores,
the VVols datastore can be browsed and lists configuration virtual volumes by
virtual machine name. Like traditional datastores, the VVols datastore supports
unmounting and mounting. However, such operations as upgrade and resize are not applicable to
theVVols datastore. The VVols datastore capacity is
configurable by the storage administrator outside of vSphere.
Thank You..
