Support for VMware Changed Block Tracking (CBT)

One of the CloudBerry advantages is support for block-level backup. Block-level backup identifies the modified parts of a file (or disk sector in case of image-based backup) and only backs up those modifications. This improves backup speed and reduces backup storage.

In CloudBerry Backup 5.8, we’re improving VMware backup with our support for VMware's Changed Block Tracking (CBT).

Support for Changed Block Tracking in ESXi

VMware ESXi virtual machines using Changed Block Tracking (CBT) automatically track any disk sectors that have been modified. CBT provides the foundation for fast block-level backups. Rather than having to scan an entire virtual volume for changes, CBT provides this information to us.  When you perform a block-level backup of a virtual machine, CloudBerry Backup requests sector changes from CBT and then quickly backs them up. CBT is very efficient and fast.

CBT is not enabled by default. You can enable the feature in CloudBerry from the VMware Backup Wizard. Click VMware on the main toolbar in CloudBerry Backup VM Edition.

Enable the Use Changed Block Tracking option. Our app then automatically attempts to enable CBT for the virtual machine you're trying to back up, as this feature is disabled on the ESXi server by default. The initial backup backs up entire virtual volumes and subsequent backups will only back up changed disk sectors as reported by Changed Block Tracking.