===== Use VSS snapshot to have consistent Windows backups =====

==== Snapshot with VSS ====

**TSM can do a:**\\
* Open File Support (OFS) backup (when snapshotproviderfs vss is in effect)\\
* Online image backup (when snapshotproviderimage vss is in effect)

__To force__ the use of VSS snapshot provider on TSM, when a system has multiple providers (for example with VMware), add the following option into dsm.opt
<code>
VSSUSESYSTEMProvider yes
</code>

You can also add to use for filesystem backups and/or image backup the VSS as provider:
<code>
SNAPSHOTPROVIDERFs VSS (other value: LVSA, none)
SNAPSHOTPROVIDERImage VSS (other value: LVSA, none)
</code>

//Debug option in client dsm.opt://
<code>
TESTFLAGS VSSSYSTEMPROVIDER
</code>

==== Diagnostic a VSS trouble ====

My vssadmin list writers command shows System Writer, ASR Writer, Shadow Copy Optimization Writer, WMI Writer, BITS Writer, Registry Writer, and COM+ REGDB Writer all as 'Stable' and 'No Error'.  When we do the vssadmin list providers command, we get no results at all.

**HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VSS\Providers**

If this registry does not have providers listed under it , we will have failures.

You could try to export this registry from a working machine and import it on the affected server. Then please reboot the machine, and use the following procedure to register the required VSS DLLs:

( this can be done through a batch file )

<cli prompt='#'>
net stop vss
regsvr32 ole32.dll /s
regsvr32 vss_ps.dll /s
Vssvc /Register
regsvr32 /i swprv.dll /s
regsvr32 /i eventcls.dll /s
regsvr32 es.dll /s
regsvr32 stdprov.dll /s
regsvr32 vssui.dll /s
regsvr32 msxml.dll /s
regsvr32 msxml3.dll /s
regsvr32 msxml4.dll /s
net start vss 
</cli>

http://kb.macrium.com/KnowledgebaseArticle50031.aspx

==== How to list snapshot providers and writers ====

To be able to use VSS on Windows, you should have at least the Microsoft Shadow Copy as snapshot provider:
<cli prompt='>'>
C:\Users\admin>vssadmin list providers
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.

Provider name: 'Microsoft Software Shadow Copy provider 1.0'
   Provider type: System
   Provider Id: {b5946137-7b9f-4925-af80-51abd60b20d5}
   Version: 1.0.0.7
</cli>

The snapshot provider is used for the following components:
<cli prompt='>'>
C:\Users\admin>vssadmin list writers
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.

Writer name: 'Task Scheduler Writer'
   Writer Id: {d61d61c8-d73a-4eee-8cdd-f6f9786b7124}
   Writer Instance Id: {1bddd48e-5052-49db-9b07-b96f96727e6b}
   State: [1] Stable
   Last error: No error

Writer name: 'VSS Metadata Store Writer'
   Writer Id: {75dfb225-e2e4-4d39-9ac9-ffaff65ddf06}
   Writer Instance Id: {088e7a7d-09a8-4cc6-a609-ad90e75ddc93}
   State: [1] Stable
   Last error: No error
.......

Writer name: 'System Writer'
   Writer Id: {e8132975-6f93-4464-a53e-1050253ae220}
   Writer Instance Id: {90ec6aa2-c915-41f9-8730-8743338018c6}
   State: [1] Stable
   Last error: No error

Writer name: 'ASR Writer'
   Writer Id: {be000cbe-11fe-4426-9c58-531aa6355fc4}
   Writer Instance Id: {7e7ff5e1-e86b-428f-a605-a4661e31243b}
   State: [1] Stable
   Last error: No error

........

Writer name: 'Shadow Copy Optimization Writer'
   Writer Id: {4dc3bdd4-ab48-4d07-adb0-3bee2926fd7f}
   Writer Instance Id: {5c15e4e2-0f0e-4c21-a03c-f6161b2fd706}
   State: [1] Stable
   Last error: No error

Writer name: 'COM+ REGDB Writer'
   Writer Id: {542da469-d3e1-473c-9f4f-7847f01fc64f}
   Writer Instance Id: {714d4b80-5f2c-422b-a869-b90c9277c345}
   State: [1] Stable
   Last error: No error

Writer name: 'Registry Writer'
   Writer Id: {afbab4a2-367d-4d15-a586-71dbb18f8485}
   Writer Instance Id: {a10f41a1-5a78-4797-8515-9be53bfc2940}
   State: [1] Stable
   Last error: No error
</cli>

==== User permission on VSS usage ====

First check the service VSS (Volume Shadow Copy) it must be stopped and manual startup.

In latest case if you are not able to bring it working with your user, do the following steps:\\
Assign the appropriate privileges to the VSS writer user account
  On the computer on which the writer is running, click Start.
  In the Start Search box, type Regedit, and then press Enter.
  Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VSS\VssAccessControl.
  Right-click VssAccessControl, point to New, and then click DWORD (32-bit) Value.
  Give the registry entry the same name as the user account. (Ex: mydomain\Administrator)
  Right-click the registry entry name, and then click Modify.
  Type 1, and then click OK. 
  
==== Windows utilities to test VSS snapshots ====

Download the following utilities on Microsoft web site

The "VSHADOW Prereq Test" (Windows 2003)

The "DISKSHADOW Prereq Test" (Windows 2008) 

http://www-01.ibm.com/support/docview.wss?uid=swg21403456
  
==== Exclude special objects from SystemState backup ====

To prevent such kind of failure\\
Systemstate backup fails with ANS5250E or ANS5279E objEnumGetNextObj or ANE4251W system writer file not found

//Problem(Abstract)//

Backup of systemstate will fail when the path to a folder or file does not exist. 
**SKIPMISSINGSYSWFILES YES** available in 6.1.4 and higher