How Windows Image Backup works
The Data Management Agent leverages Windows Server Backup's “wbadmin” command with the “–allCritical” parameter set (also known as a Bare Metal Backup). When the backup occurs, all files, including non-system files that reside on volumes used by the operating system, are temporarily stored in consolidated format in the “WindowsImageBackup” folder.
- The WindowsImageBackup folder will only be stored on a volume that is not included in the backup. A backup could be prevent if such a volume is not available.
- Because of this consolidation, no deduplication can performed on the data.
While performing a backup with Windows Image Backup enabled i.e. the All critical volumes setting in the DM Agent's Options and Settings, the following entries are displayed in the backup log:
2015-02-18 10:08:04,241 INFO Shell - WIB: The backup storage location is invalid. You cannot use a volume that is included in the backup as a storage location.
2015-02-18 10:08:05,553 ERROR Shell - Shell command exited with exit code=-3, command: wbadmin start backup -allCritical -quiet -backupTarget:E:
2015-02-18 10:08:08,334 ERROR ScanErrorLogger - Skipping: E:\WindowsImageBackup (Directory E:\WindowsImageBackup is unavailable)
During the backup process, the information of the critical volumes being backed up is temporarily stored on the same machine before being transferred to the Storage Platform. This means that the storage location cannot also be a system volume.
However, the drive letter indicated in the log entries was inadvertently designated a "system" volume (highlighted above as an example) and was not detected when Windows Image Backup was enabled. This is due to an application that has been installed on that volume, i.e. the Agent.
Review the contents of the volume on the drive letter indicated in the log entries and select a different drive letter for the Dump destination in the Agent's Options and Settings dialog box.