HP 3PAR VSS Provider Software - Manual (Page 5)

2 Overview
This chapter provides an overview of supported components and system requirements for HP 3PAR
VSS Provider Software for Microsoft Windows.
Microsoft VSS
Microsoft includes VSS in the Windows 2008, Windows 2008 R2, and Windows 2012 operating
systems to simplify the enterprise’s storage environment. VSS provides a framework for creating a
point-in-time copy of a single volume or multiple volumes.
Microsoft Windows Server 2008, Microsoft Windows Server 2008 R2, and Microsoft Windows
Server 2012 VSS work with VSS-aware applications to determine when a volume shadow copy
(snapshot) can be made. A snapshot is a copy of some data set (for example, a disk volume) at
a given point-in-time.
HP 3PAR VSS Provider for Microsoft Windows-Aware Components
Microsoft provides a Software Development Kit (SDK) to enable independent hardware and software
vendors to interface with their components. This includes applications, data stores, snapshot engines,
and backup applications that interface with HP 3PAR VSS Provider Software for Microsoft Windows.
HP 3PAR VSS Provider for Microsoft Windows is developed with VSS SDK, release 7.2 for Windows
2003 and Windows Server 2008 Platform SDK, as a part of the HP 3PAR VSS Provider
implementation.
To ensure absolute data integrity for all volumes, especially volumes that are interrelated, the
application, the backup program, and the backup device must be VSS aware. This means that the
components participating in the backup must be specifically programmed to work with HP 3PAR
VSS Provider for Microsoft Windows. These components are called writers, requestors, and
providers, and are described in detail in
Table 1 (page 5) .
Table 1 HP 3PAR VSS Provider for Microsoft Windows Components
VSS Component Description VSS Component
The requestor is a backup software that initiates the creation of the shadow
copy. Requestor
The writer is any application software that participates in the shadow copy
process and whose files and data are included in the process. Writer
The provider is the storage technology that performs the actual shadow copy. Provider
Operation of HP 3PAR VSS Provider for Microsoft Windows
HP 3PAR VSS Provider for Microsoft Windows Figure 1 (page 6) communicates with the operating
system and applications, and temporarily freezes computing tasks to allow for the creation and
removal of snapshots. The freeze function allows for the creation of a snapshot that reflects the
state of application data at a given point in time. When the process resumes, the original volume
will continue to change while the shadow copy of the volume remains constant.
HP 3PAR VSS Provider for Microsoft Windows also provides permission for the backup application
to access the volume and back it up in its frozen state. The shadow copy volume is then used for
the actual backup. After the shadow copy volume is saved on the backup device, the shadow copy
is deleted.
Microsoft VSS 5