HP SAN Virtualization Services Platform - Manual (Page 119)

• The client will recursively traverse down BasedOn associations (via the Antecedent) to examine
the underlying extents.
• If a CompositeExtent is encountered, the client examines the associations to the CompositeExtent
and traverses the associations to discern how the CompositeExtent is constructed. The RAID level
and the storage pool association is discovered.
• The client will continue traversal of associations downward to the primordial extents. Primordial
extents are those associated with the primordial pool in the Block Services Package.
• Once the client reaches the primordial extents, the client should have a snapshot of how primordial
extents are organized into CompositeExtents, and hence, will have a snapshot of the quality of
service of the virtual disk and the storage pool association of elements comprising the storage
pool.
Find the primordial extents used by a virtual disk
It may be desirable for a client to snapshot the physical drives comprising a virtual disk, or what
virtual disks are mapped on a drive. Clients may be interested in preventing multiple high-use virtual
disks being spanned across one drive, or identifying how the failure of a drive or virtual disk spans
across elements.
• A client starts with a virtual disk element, HPSVSP_VirtualDisk (from Block Services).
• The client will traverse from the storage virtual disk with a BasedOn association (with the Antecedent)
through the underlying extents until the client encounters HPSVSP_ImportedExtent. These extents
will be the primordial extents that comprise the given virtual disk.
Classes
HPSVSP_VirtualDiskBasedOn : CIM_BasedOn
Class introduction
This is the 1 to 1 mandatory association between the two sibling classes representing different aspects
of the virtual disk.
Since this occurrence of BasedOn associates two instances that represent the same thing, a virtual
disk, and both the DeviceID primary key values are the virtual disk name.
Class keys/properties
Comments Property name
Mandatory HPSVSP_VirtualDisk : CIM_StorageVirtualDisk REF Dependent
Mandatory HPSVSP_VirtualDiskCompositeExtent : CIM_CompositeExtent REF Antecedent
HPSVSP_VirtualDiskCompositeExtent : CIM_CompositeExtent
Class introduction
This class is the HPSVSP_VirtualDisk storage virtual disk from the Block Services Profile represented
as an extent. There must be one instance of this class for each HPSVSP_VirtualDisk in Block Services.
SAN Virtualization Services Platform SMI-S User Guide 119