How to troubleshoot Hyper-V VSS writer causing backup failure on Server 2008 R2
- by Tim Anderson
I have a Windows Server 2008 R2 machine running Hyper-V. Backups using Windows Server Backup fail with the error:
The backup operation that started at '?2011?-?01?-?02T10:37:01.230000000Z' has failed because the Volume Shadow Copy Service operation to create a shadow copy of the volumes being backed up failed with following error code '2155348129'. Please review the event details for a solution, and then rerun the backup operation once the issue is resolved.
I have traced this to a problem with the Hyper-V VSS writer. vssadmin list writers reports:
Writer name: 'Microsoft Hyper-V VSS Writer'
Writer Id: {66841cd4-6ded-4f4b-8f17-fd23f8ddc3de}
Writer Instance Id: {fcf0dd79-d282-4465-88ae-7b6857e055c2}
State: [8] Failed
Last error: Inconsistent shadow copy
However I can't get any further. A few relevant facts:
I get the error even if all the VMs are shut down
If I disable the Hyper-V VSS Writer by stopping the Hyper-V Management Service backup completes OK
There are no errors in the Hyper-V-VMMS application log
I tried to set tracing for VSS but can't get any output for some reason. I set the correct registry entries but no trace log is generated.
Tim
