When and how to use quiescing with SQL or Exchange servers and other VSS aware applications with (4047331)

How to configure a VM to get an application level consistent backup.

vRanger can provide three different levels of backup consistency, as described below:

Crash-consistent - A crash consistent backup is analogous to pulling the plug on a server and then backing up the data. The state of the data that is being backed up with respect to the users of the data is indeterminate. Restoring a crash-consistent image is equivalent to rebooting a server after a hard shut-down.

File System Consistent - File system consistency is achieved through standard quiescing (via the VMware Sync Driver.) which ensures that no file system writes are pending when the snapshot is taken. For normal VMs, file-system consistency is adequate, although it can cause corruption in database applications.

Application consistent - Consistency of VSS compatible applications is achieved by freezing application I/O just prior to creating the VM snapshots. This ensures that all application writes requests in the machines memory are committed to disk before the snapshot is taken. Application consistency is achieved by leveraging the VSS driver in VMware Tools.

Note: The following does not apply to ESX console (Direct to Target) backups of Windows 2008/R2 VM's. Quiesced ESX console backups of Windows 2008 VM's will use this configuration: Disk_UUID=FALSE + vzshadow.

1. Please enable guest quiescing in tasks to freeze VSS aware applications.

2. Using the table below, determine what configuration your VM needs.
   
   Note:VMware tools should be the installed on all VMs. VMware VSS refers to the VSS driver in VMware Tools along with the VM's Disk_UUID setting set. The VSS driver is an optional component of VMware tools. In some cases a complete re-install of VMware tools maybe needed to install the VSS driver. Instructions on setting the Disk_UUID variable can be found here - Http://kb.vmware.com/kb/1028881.

   File Level Quiescing	Windows 2003	Windows 2008/R2
   ESX(i) 4.0	VMware VSS	VMware VSS
   ESX(i) 4.1 Update 1 +	VMware VSS	VMware VSS
   ESXi 5.0	VMware VSS	VMware VSS
   App Level Quiescing	Windows 2003	Windows 2008/R2
   ESX(i) 4.0	VMware VSS	VMware VSS
   ESX(i) 4.1 Update 1 +	VMware VSS	VMware VSS
   ESXi 5.0	VMware VSS	VMware VSS
   Truncate Exchange Logs	Windows 2003	Windows 2008/R2
   ESX(i) 4.0	VMware VSS & vzShadow
   ESX(i) 4.1 Update 1 +	VMware VSS & vzShadow
   ESXi 5.0	VMware VSS & vzShadow

3. How to deploy vzShadow.exe if necessary:
   
   NOTE: vzShadow.exe works in conjunction with VMware Tools. VMware Tools must be installed and running on the VM when using vzShadow.exe.
   
   vRanger 5.3.x and earlier:
4. 1. Download and install the appropriate C++ Redistributable package on the same machine that hosts the VSS aware application you want to quiesce.
      For 64-bit (x64) machines, go to:http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=15336

      For 32-bit (x86) machines, go to:http://www.microsoft.com/downloads/details.aspx?FamilyID=9b2da534-3e03-4391-8a4d-074b9f2bc1bf&displaylang=en#RelatedLinks

   2. The installed vRanger software (version 4.5 and later) contains two files. The files can be found:
      \Program Files\Vizioncore\vRanger\VSS (vRanger 4.x) - Installed on 32bit O/S
      \Program Files\Quest Software\vRanger\VSS (vRanger 5.x) - Installed on 32bit O/S
      
      \Program Files(x86)\Vizioncore\vRanger\VSS (vRanger 4.x) - Installed on 64bit O/S
      \Program Files(x86)\Quest Software\vRanger\VSS (vRanger 5.x) - Installed on 64bit O/S

   3. Depending on your bit O/S level of your system, copy the appropriate file (From point #2) to the root directory of the VM which hosts the VSS aware application. (typically the "C:\" )
      For 64bit O/S copy vzShadow_x64.exe
      For 32bit O/S copy vzShadow_x86.exe

   4. Create a directory on the VM:
      C:\Program Files\VMware\VMware Tools\backupscripts.d\

   5. In this directory, create a batch file called freeze.bat.
      For 32 bit Operating System:
      -Edit the freeze.bat file and add the line:
      c:\vzshadow_x86.exe x:
      
      For 64 bit Operating System:
      -Edit the freeze.bat file and add the line:
      c:\vzshadow_x64.exe x:
      
      Where X equals the drive that hosts the application.
      
      If there are multiple volumes on this VM, list all volumes, separated by colon space (: )
      c:\vzshadow_xXX.exe c: d: e:
      
      (When a quiesced snapshot is triggered by VMware tools, the pre-freeze script will execute vzShadow)

   6. Execute the backup job.
      
      Note: Alternative VSS script location (if quiescing does not work OR ESX(i) hosts have been upgrade from 3.x to 4.x)
      Create a batch file in "C:\Windows" called: "pre-freeze-script.bat".

• Event ID 9610 (Exchange VSS Snapshot has frozen the storage groups successfully)
• Event ID 9612 (Exchange VSS Snapshot has thawed the storage groups successfully)
• Event ID 9616 (Exchange VSS Snapshot has truncated the logs successfully)
• Event ID 9648 (Exchange VSS Snapshot backup has been shutdown successfully)

• How Volume Shadow Copy Service Works
• Troubleshooting Volume Shadow Copy (VSS) quiesce related issues
• vRanger integration with RME process workflow

For vRanger 5.4 and newer, view https://support.quest.com/Search/SolutionDetail.aspx?id=SOL93858