You can monitor the changes that occur on virtual disks by enabling Changed Block Tracking (CBT) for your backups.
Before You Begin
To use CBT-enabled backups, install the Virtual Server Agent (VSA) software on the Azure proxy.
Procedure
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From the CommCell Browser, expand Client Computers > virtualization_client > Virtual Server > Azure > backup set.
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Right-click the subclient, and then select Properties.
The Subclient Properties dialog box appears.
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On the Backup Options tab, select or deselect the Use Changed Block Tracking checkbox, and then click OK.