Low Level Backup
Procedures
This section describes low level details
that may be helpful in coding a backup application. It is not the intent of
this material to impose a design, but only to serve as a guideline with
examples and exposition. The code samples provided below are not complete. They
generally lack error handling and ignore critical details.
Communicate with the Server The PropertyCollector PropertyCollector is used in this section to apply the above details to the backup task. Creating a Snapshot Backing Up a Virtual Disk VixDiskLib . The following code shows how to initialize the VixDiskLib and use it for accessing a virtual disk. All operations require a VixDiskLib connection to access virtual disk data. At the present time VixDiskLib is not implemented for the Java language, so this code is C++ language:Deleting a Snapshot moRef for the snapshot from taskRef.info.result as describe above for the create snapshot operation. The following Java code demonstrates how to delete the snapshot:New Query Allocated Blocks Function VixDiskLib_QueryAllocatedBlocks to accelerate the backup process, especially with large virtual disks. By knowing which blocks are allocated, an application can avoid reading irrelevant sectors and thus reduce data transfer during backup. Changed Block Tracking on Virtual Disks QueryChangedDiskAreas , which takes the following parameters: