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Troubleshooting guide: Fixing the 'Couldn't determine changeId of this device key: 2000' error during virtual machine backup

Problem:

A problem with Change Tracking (CTK) is indicated by the error message "Couldn't determine changeId of this device key: 2000," which appears during virtual machine (VM) backups. CTK helps backup software identify changes made to VMs, enabling efficient backups.

Cause:

The issue occurs when Zmanda Classic cannot identify the change ID (unique identifier) for a particular device in the VM, usually because CTK is turned off.

Solution:

To fix this error perform the following steps in the vSphere web client:

  1. Power off the VM completely before proceeding.

  2. Right-click the affected VM and select Edit Settings.

  3. Navigate to the VM Options tab within the settings window.

  4. Click on Advanced and then select Edit Configuration next to Configuration Parameters. This action will open the Configuration Parameters dialog box.

  5. Click Add parameters and add the parameter named ctkEnabled. Set its value to true.

  6. Again, click Add parameters and add the parameter named scsi0:0.ctkEnabled. Set its value to true.

  7. Power on the VM.

  8. After powering on, go back to Edit Settings > VM Options > Advanced > Edit Configuration. Ensure ctkEnabled and scsi0:0.ctkEnabled parameters are present and set to true.

Following these steps should resolve the "Couldn't determine changeId of this device key: 2000" error during VM backups. If problems persist, contact our support team for further assistance.