Differential backup of VMWare virtual machine processes entire provisioned VMDK instead of only changes


Differential backup of VMWare virtual machine processes entire provisioned VMDK instead of only changes

Error Message

Beremote debug log on Backup Exec server shows:

[2640] [fsys\vmvcb]         - AVVI Buffered Reads Performance Tuning is Enabled.
[2640] [fsys\vmvcb]         -         Number of Read Buffers: '4'
[2640] [fsys\vmvcb]         -         Size of Read Buffers: '1024'KB
[2640] [fsys\vmvcb]         -         Read Thread Priority: 0 - Normal.
[2640] [fsys\shared]        - startReadCacheThread(): Allocating 4 buffers of size 1024
[1564] [fsys\shared]        - VixDiskLib_Read(): Read thread '1564' Start
[2640] [fsys\vmvcb]         - VM_VCBPROXY_FS::GetDiskChangedInfo: GetDiskChangedInfo for VM=<Path of Virtual Machine>\<VMName>, snapName=SYMC-UNKNOWN 07-11-2013 11:45, changeId=, DiskName=[<DataStore>] <VM Name>/<VM Name>.vmdk, Key=2000, offset=0
[1564] [fsys\shared]        - initializeCom Failed to Get Status
[2640] [fsys\vmvcb]         - SymVmTools: IsChangeTrackingEnabledAPI: Enabled = true, Supported = true
[2640] [fsys\vmvcb]         - SymVmTools: GetDiskChangedInfoAPI: entered: deviceKey = 2000, snapshotName=SYMC-UNKNOWN 07-11-2013 11:45, vmPath= <Path of Virtual Machine>\<VM Name>
[2640] [fsys\vmvcb]         - SymVmTools: GetDiskChangedInfoAPI: deviceKey = 2000, vmMor=vm-2458, diskCapacity(bytes)=42949672960
[2640] [fsys\vmvcb]         - SymVmTools: GetDiskChangedInfoAPI: SYM_VMC_ERROR:  SOAP_ERROR
[2640] [fsys\vmvcb]         - SymVmTools: SOAP 1.1 fault: "":ServerFaultCode [no subcode]
"A specified parameter was not correct.


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Symantec Corporation has acknowledged that the above-mentioned issue is present in the current version(s) listed under the Product(s) Section of this article. Symantec Corporation is committed to product quality and satisfied customers.
This issue is currently under investigation by Symantec Corporation. Pending the outcome of the investigation, this issue may be resolved by way of a patch or hotfix in current or future revisions of the software. However, this particular issue is not currently scheduled for any release.  If you feel this issue has a direct business impact for you and your continued use of the product, please contact your Symantec Sales representative or the Symantec Sales group to discuss these concerns.  For information on how to contact Symantec Sales, please see 
http://www.symantec.com Please be sure to refer back to this document periodically as any changes to the status of the issue will be reflected here.

Applies To

Backup Exec 2010 R3

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