Search the VMware Knowledge Base (KB)
View by Article ID

Deploying or recomposing View desktops fails when the parent virtual machine has CBT enabled (2032214)

  • 12 Ratings


  • Deploying or recomposing View desktops when Changed Block Tracking (CBT) is enabled on the parent virtual machine fails
  • VMware View Events display this error:

    Failed to perform space reclamation on machine Machine_Name in pool Pool_Name

  • vCenter Server reports this error:

    A general system error occurred: Wipe Disk failed: Failed to complete wipe

  • In the vmware-viewcomposer.log file, you see entries similar to:

    <YYYY-MM-DD>T<TIME>,077 | VC thread | FATAL | CommonLib.VcSubsystem.LroVcTask - Got VcFault: VMware.Sim.CommonLib.Exception.SimVcSubsystemException: Error caused by file /vmfs/volumes/[VOLUME]/[VM]/[VM]-MR-000001.vmdk ---> System.Web.Services.Protocols.SoapException: Error caused by file /vmfs/volumes/[VOLUME]/[VM]/[VM]-MR-000001.vmdk

    Note: The vmware-viewcomposer.log file is located at:

    • Windows 2003 – C:\Documents and Settings\All Users\Application Data\VMware\View Composer\Logs\
    • Windows 2008 – C:\ProgramData\VMware\View Composer\Logs\

  • In the /var/log/vmware/vpxa.log file on the ESXi host, you see entries similar to:
DISKLIB-CTK : Could not open tracking file. File open returned IO error 4.
DISKLIB-CTK : Could not open change tracking file "/vmfs/volumes/UUID/parent vm name-ctk.vmdk": Could not open/create change tracking file.
DISKLIB-LIB : Could not open change tracker /vmfs/volumes/UUID/parent vm name-ctk.vmdk: Could not open/create change tracking file.
DISKLIB-LIB : Failed to open '/vmfs/volumes/UUID/parent vm name-000002.vmdk' with flags 0x21e Could not open/create change tracking file (2108).
[NFC ERROR] NfcFileDskOpenDisk: Failed to open '/vmfs/volumes/UUID/parent vm name-000002.vmdk': Could not open/create change tracking file (2108).
[NFC ERROR] NfcFile_Open: Open failed:
[NFC ERROR] NfcFile_Clone: Failed to open source file
[VpxNfcClient] File transfer [ds:///vmfs/volumes/UUID/parent vm name-000002.vmdk-> ds:///vmfs/volumes/UUID/replica-<id>/replica-<id>.vmdk] failed.
[VpxNfcClient] NFC file error for file ds:///vmfs/volumes/UUID/parent vm name-000002.vmdk
[VpxNfcClient] Closing NFC connection to server

Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.  


This issue occurs when Changed Block Tracking (CBT) is enabled on the parent virtual machine.


This is issue resolved in ESXi 5.0 P10 , ESXi 5.5 P08 and ESXi 6.0 EP06 and P03. To download patches refer the VMware Patch Downloads

If this issue occurs occurs on ESXi 5.1 then upgrade to ESXi 5.5 P08.  

To work around this issue, disable CBT on the parent virtual machine.
Note: Ensure that there are no snapshots on the parent virtual machine. For more information, see Consolidating snapshots in vSphere 5.x (2003638).
To disable CBT:
  1. Power off the virtual machine.
  2. Right-click the virtual machine and click Edit Settings.
  3. Click the Options tab.
  4. Click General under the Advanced section, then click Configuration Parameters
  5. Set the ctkEnabled parameter to false for the corresponding SCSI disk.

    For Example:
    • Settings changed per device:

    • Settings changed for all devices:
To prevent any third-party applications from enabling Change Block Tracking on the virtual machine:
  1. Open the .vmx file of the virtual machine using a text editor.
  2. Add this entry to the file:


    For more information, see Tips for editing a .vmx file (1714).

  3. Save and close the file.

Additional Information

To be alerted when this article is updated, click Subscribe to Document in the Actions box. 

For more information on CBT, see Changed Block Tracking (CBT) on virtual machines (1020128).

See Also

Update History

02/07/2013 - Added the line about how to disallow change tracking to be turned on the Resolution section 7/17/2014 - Added examples of ctkEnabled parameter to false under Resolution

Request a Product Feature

To request a new product feature or to provide feedback on a VMware product, please visit the Request a Product Feature page.


  • 12 Ratings

Did this article help you?
This article resolved my issue.
This article did not resolve my issue.
This article helped but additional information was required to resolve my issue.

What can we do to improve this information? (4000 or fewer characters)

Please enter the Captcha code before clicking Submit.
  • 12 Ratings