Successful Guest Machine Backup - Full Scan Due to CBT Failure

Backup completed successfully for Guest machine(A full scan was taken owing to CBT failure)

KB ID: 104049
Issue:
Backup Completed Successfully for Guest Machine - Full Scan Triggered Due to CBT Failure
Cause:
This alert occurs when a full scan of the disks (non-CBT mode) is performed before an incremental Hyper-V backup. The incremental backup takes the same amount of time as a full backup in this scenario. A full scan is initiated when the VembuCBT driver fails, which can happen when changed blocks on the disks cannot be tracked while the VIS service is running in the local account on any of the added SOFS file server nodes (applicable to Windows 2012 R2).
Solution:
To resolve this issue, it is recommended to run the VIS (VembuIntegrationService) service with specific account privileges on all SOFS file server nodes. Follow these steps to modify user credentials for the VembuIntegrationService:
Step 1: Open the Run window (Press Win + R), type "services.msc," and press Enter to open the Service Manager console.
Step 2: In the list of services, locate "VembuIntegrationService," right-click it, and select "Properties."
Step 3: Go to the "Logon" tab and choose "Log on as a specific account." Provide the credentials of a user with administrative privileges, and click "Save."
Step 4: Restart the Vembu Integration Service.
By following these steps, you can ensure that the VIS service runs with the necessary account privileges on all SOFS file server nodes, resolving the issue of full scans triggered by CBT failure during Hyper-V backups.