User`s guide

Chapter 5
Performing Image-Level Backups
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Important Notes
 During the first Full Backup that is run with the Enable Changed Block
Tracking for VM option selected, the target virtual machine must be powered
off. During the subsequent Full, Incremental, or Differential Backups, the
virtual machine can remain powered on.
 At the time of enabling CBT, no snapshots should exist on a virtual machine.
For more information, refer to http://kb.vmware.com/kb/1033816
.
 The re-configuration of this parameter will take effect only after the virtual
machine goes through a stun/unstun cycle, including power on, resume after
suspend, migrate, or snapshot create, delete, or revert operations.
 During an Incremental or Differential Backup, the plug-in will not attempt to
enable CBT for any virtual machine included in the backup, unless you have
selected the Enable Change Block Tracking for VM check box for the job.
 If a new virtual machine is included in a Backup Selection Set after the initial
Full or any subsequent Incremental or Differential Backup (for example, the
Selection Set is modified to include a new virtual machine, or a new virtual
machine is added to the ESX Server included in a Selection Set), the plug-in
will do the following:
 Create a Full Backup of the new virtual machine if you run an Incremental
or Differential Backup after adding the virtual machine.
 Create a non-CBT Full Backup, unless CBT is already enabled for the
virtual machine or you have selected the Enable Change Block Tracking
for VM check box on the Backup Options tab for the Incremental or
Differential Backup.
 Perform the subsequent backups of the new virtual machine as
Incremental/Differential or Full depending on whether CBT is enabled or
not, and a Full Backup has been performed with CBT or not.
 Once you enable CBT for a virtual machine, all subsequent Full, Incremental,
and Differential Backups will be performed as CBT-based backups for that
virtual machine. You do not have to select the Enable Changed Block
Tracking for VM check box for each job.
To stop using CBT, you must disable this feature. For instructions, see
Disabling CBT for a Virtual Machine.
 If you perform a Full Backup of a Thick Provisioned Lazy Zeroed disk without
enabling CBT, the data in the empty sectors will be converted to actual zeros
during backup. When you restore the backup, the disk type will change to
Eager Zeroed.