HP StorageWorks EVA Hardware Providers administration guide Windows 2003 (T1634-96052, February 2006)

Copy terminology
Understanding how Microsoft VSS terminology corresponds to standard IT industry
terms for data copying makes it easier to u nderstand what V SS does. The following
paragraphs explain the terminology.
Microsoft generally refers to a VSS copy as a “volume shadow copy.” When created
usingHPFRSandHWP,thistypeofcopyisastaticreplicaofanoriginalvolume’s
contents. It is keyed with a GUID to allow identification of the parts of a shadow copy
setthatspanmul
tiple volumes. Microsoft also refers to a VSS copy as a “plex.” This type
of copy is commonly referred to in the IT industr y as a “split mirror.”
When you use an EVA array to m a ke a sha dow co py, the array makes what is known
as a “snapclone
.” An EVA S napclone is a complete clone copy of a specified Virtua l
Disk (LUN). EVA snapclones are available almost immediately. This is accomplished
by creating a point-in-time copy and making it immediately available by pointing to
data on the ori
ginal volume while continuing to copy data to a secondary volume in
the background. When co pying is complete, the snapclone is a static point-in-time
copy of the original.
HP VDS/VSS Hardware Providers
Windows Server 20 03 sees, par titions, m o unts, and m anag es fi le systems on the disk
array using its own software providers. HP’s Hardware Providers extend the array
management capabilities of Windows and its applications to include functions normally
performed using the disk array’s proprietary control software. These functions include
managing disk array LUNs and ports and performing volume copy operations.
There are t wo H P HWP installation executables for each HP disk array model, one
installation executable for VDS a nd one for VSS. These installation executables are
different for each HP disk array m o del.
The HP Hardware Providers installation executables i nstall the HWP files in your
Windows Server file system. The files installed consist of special sets of HP DLLs and
exe cutables. These components extend the array mana gem ent capabilities of Windows
and its applications. Because they are installed separately, you can choose to install
only the VDS or VSS HWP or both.
For VSS only, HP’s Business Copy (BC) application, which installs on the disk array and
is licensed in Command View, works with the VSS and the HP HWP components to
enable the array to m ake VSS shadow copies. For functional purposes, you can think of
BC as a part of the hardware providers, even though it is installed separately.
HP disk arrays
Speci
fic HP H ardware P roviders have been created to work with selected HP d isk arrays.
Different supporting technologies and features within the arrays result in some differences
in their methods and capabilities of performing VDS/VSS tasks.
HP StorageWorks EVA Hardware Providers administration guide Windows 2003
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