6.0.1

Table Of Contents
After you register a storage provider associated with the storage system, vCenter Server discovers all
congured storage containers along with their storage capability proles, protocol endpoints, and other
aributes. A single storage container can export multiple capability proles. As a result, virtual machines
with diverse needs and dierent storage policy seings can be a part of the same storage container.
Initially, all discovered storage containers are not connected to any specic host, and you cannot see them in
the vSphere Web Client. To mount a storage container, you must map it to a virtual datastore.
Protocol Endpoints
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 les 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 specic 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.
On the storage side, a storage administrator congures protocol endpoints, one or several per storage
container. Protocol endpoints are a part of the physical storage fabric and are exported, along with
associated storage containers, by the storage system through a storage provider. After you map a storage
container to a virtual datastore, protocol endpoints are discovered by ESXi and become visible in the
vSphere Web Client. Protocol endpoints can also be discovered during a storage rescan.
In the vSphere Web Client, the list of available protocol endpoints looks similar to the host storage devices
list. Dierent storage transports can be used to expose protocol endpoints to ESXi. When the SCSI-based
transport is used, the protocol endpoint represents a proxy LUN dened by a T10-based LUN WWN. For
the NFS protocol, the protocol endpoint is a mount-point, such as IP address (or DNS name) and a share
name. You can congure multipathing on a SCSI based protocol endpoint, but not on an NFS based protocol
endpoint. However, no maer which protocol you use, a storage array can provide multiple protocol
endpoints for availability purposes.
Virtual Datastores
A virtual 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 virtual datastore. The virtual datastore that you create corresponds directly to the specic
storage container and becomes the container's representation in vCenter Server and the vSphere Web Client.
From a vSphere administrator prospective, the virtual datastore is similar to any other datastore and is used
to hold virtual machines. Like other datastores, the virtual datastore can be browsed and lists virtual
volumes by virtual machine name. Like traditional datastores, the virtual datastore supports unmounting
and mounting. However, such operations as upgrade and resize are not applicable to the virtual datastore.
The virtual datastore capacity is congurable by the storage administrator outside of vSphere.
You can use virtual datastores with traditional VMFS and NFS datastores and with Virtual SAN.
N The size of a virtual volume must be a multiple of 1 MB, with a minimum size of 1 MB. As a result,
all virtual disks that you provision on a virtual datastore or migrate from any datastore other than the
virtual datastore should be an even multiple of 1 MB in size. If the virtual disk you migrate to the virtual
datastore is not an even multiple of 1 MB, extend the disk manually to the nearest even multiple of 1 MB.
vSphere Storage
216 VMware, Inc.