vRanger and Changed Block Tracking (87862)

Changed Block Tracking, is a feature of vSphere (Driver is within the VMkernel). CBT identifies changed blocks within a VM’s disk, and logs these in a tracking file.

vRanger can utilize VMware's CBT feature to reduce the time needed for backups and replications, by only utilizing the blocks that have changed. This will often result in reduced resource consumption for network and storage elements.

CBT is not enabled by default. Please note, that utilizing CBT does impose minimal overhead on the associated ESX(i) host.

Pre-Requisites:

• The host must be ESX(i) 4.0 or later (with updated VMware tools).
• The virtual machine owning the disks to be tracked must be hardware version 7 or later.
• CBT is limited to VMDK’s & vRDM ‘s.

To Enable CBT using vRanger:

• On the "My Inventory Screen" right click a VM.
• Select "Enable Change Tracking".
• The tracking (three squares) icon will appear next to any VM with CBT enabled.
• The VM must then go through a stun/unstun cycle to activate tracking. Take and remove a snapshot on the VM to accomplish this.