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vishal1984's avatar
vishal1984
Level 3
13 years ago

is there any connection between shadow copy components & volume shadow copy.

Volume shadow copy: A shadow copy is a snapshot of a volume that duplicates all of the data that is held on that volume at one well-defined instant in time.

How we configured shadow copies.

  1. Click Start, and then click Computer.
  2. Right-click any of the volumes listed (D drive), and then click Configure Shadow Copies.
  3. Click the volume that is currently used for the volume shadow copy storage area, and then click Settings.

    Note: If shadow copies of the volume are enabled, you must first disable them by clicking the volume, and then clicking Disable.

  4. Set the volume shadow copy area volume to a volume with more storage capacity by selecting the volume from the drop-down list under Storage area, and then click OK.
  5. Make sure that the volume is still selected, and click Enable. If you are asked to confirm that you want to enable shadow copies, click Yes.

By default shadow copis are created at twice a day 12 pm & 7 am.

Shadow Copies  uses the Volume Snapshot driver (Volsnap.sys) to create shadow copies in Windows. This driver uses storage space allocated on a volume to maintain a snapshot of the contents of the shared folders. This storage space is called the Diff Area.

 

** Under the backup exec job selection > shadow copy components, it contains service state. System state.

My job starts during non business hours. shadow copy components & system state backup failed stating querying writer status. Few vss writers gets failed too.

Application event id : 12297 logged by VSS   states that, Volume Shadow Copy Service error: The I/O writes cannot be flushed during the shadow copy creation period on volume.
 
System event id : 9 logged by Volsnap,  It states that, The flush and hold writes operation on volume D: timed out while waiting for file system cleanup.

The backup job log states about vss error : Unable to get minimum quiet time for physical volumes. Reduce the activity on these volumes, or wait and run the backup job when there is less activity on volume.

Backup job scheduled to run at 11 pm.

when shadow copies are disabled on the VOLUME D. shadow copy components & system state backup succeeds.

When shadow copies are enable on the VOLUME D. shadow copy components & system state backup fails.

 

What is the connection between [VOLUME SHADOW COPY] & [SHADOW COPY COMPONENTS & SYSTEM STATE]?

Why system state & shadow copy backup job fails when volume / D drive shadow copy is enable ? 

Backup and Recovery
Backup Exec
  • vishal1984's avatar
    vishal1984
    13 years ago

    Thank you NICK & PKH.

    I have researched & found,

    My symantec endpoint protection has been running during non business hours. It captures the shadow copies during scanning process Ultimately backup exec job failed to backup shadow copies.

    This issue has solved by rescheduling antivirus scanning at different time.

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  • pkh's avatar
    pkh
    Moderator
    13 years ago

    When you activate volume shadow copies, the saved previous versions of changed files are backed up when you backup the shadow copy components.

    Check that your volume shadow copies backups are o.k.  They may have problems and in turn cause BE to fail.  I am using volume shadow copies and I have no problems backing them up with BE 2010.

  • Nick_Elmer's avatar
    Nick_Elmer
    Level 6
    13 years ago

    Hi Vishal1984,
    I did some searching on technet and found the following link which offers recommended solutions for the VSS failure.

    Application event id : 12297 logged by VSS states that, Volume Shadow Copy Service error: The I/O writes cannot be flushed during the shadow copy creation period on volume.
     

    http://technet.microsoft.com/en-us/library/dd364933(WS.10).aspx

    Resolve

    Monitor the system performance and resources

    This event indicates that the computer is low on memory or disk resources or that the system I/O load is very high.

    Possible resolutions include:

    • Reduce the system or I/O load and retry the operation, or schedule Volume Shadow Copy Service (VSS) or other operations during the least busy periods for the computer.
    • Check the shadow copy storage area configuration and determine whether it needs to be changed.
    • If necessary, move the shadow copy storage area (also called the "diff area") to a volume with more storage capacity.

    From Wikipedia:

    Shadow Copy (Volume Snapshot Service or Volume Shadow Copy Service or VSS), is a technology included in Microsoft Windows that allows taking manual or automatic backup copies or snapshots of data, even if it has a lock, on a specific volume at a specific point in time over regular intervals. It is implemented as a Windows service called the Volume Shadow Copy service. A software VSS provider service is also included as part of Windows to be used by Windows applications. Shadow Copy technology requires the file system to be NTFS to be able to create and store shadow copies. Shadow Copies can be created on local and external (removable or network) volumes by any Windows component that uses this technology, such as when creating a scheduled Windows Backup or automatic System Restore point.

    So, What is the correlation? Well, Backup Exec uses VSS to perform System State and Shadow Copy Component backups. Volume Shadow Copy also uses VSS as well. It may be that when Volume Shadow Copies are enabled on a volume, then VSS uses the specified free space, and when they are disabled, then Backup Exec uses an alternate free space for the file changes during the backup. Its been awhile since I tested that area of the product, so I'm going from memory here. and things may have changed.

    Hope that helps,
    Nick

  • vishal1984's avatar
    vishal1984
    Level 3
    13 years ago

    Thank you NICK & PKH.

    I have researched & found,

    My symantec endpoint protection has been running during non business hours. It captures the shadow copies during scanning process Ultimately backup exec job failed to backup shadow copies.

    This issue has solved by rescheduling antivirus scanning at different time.