Snapshot Failed duplicati 2.0.3.11

Support
1

Hello
I am using duplicati in version 2.0.3.11 enabled --snapshot-policy = On The first backup was performed successfully with this option enabled.
But backup backups are experiencing this problem.
The VSS feature is installed, my operating system is Windows 20012.
Follow the warnings.

DeletedFiles: 10
DeletedFolders: 0
ModifiedFiles: 502
ExaminedFiles: 1076969
OpenedFiles: 715
AddedFiles: 213
SizeOfModifiedFiles: 609608178
SizeOfAddedFiles: 6131349
SizeOfExaminedFiles: 80588454929
SizeOfOpenedFiles: 615844690
NotProcessedFiles: 0
AddedFolders: 97
TooLargeFiles: 0
FilesWithError: 0
ModifiedFolders: 0
ModifiedSymlinks: 0
AddedSymlinks: 0
DeletedSymlinks: 0
PartialBackup: False
Dryrun: False
MainOperation: Backup
ParsedResult: Warning
Version: 2.0.3.11 (2.0.3.11_canary_2018-09-05)
EndTime: 9/11/2018 12:07:22 AM (1536635242)
BeginTime: 9/11/2018 12:00:00 AM (1536634800)
Duration: 00:07:22.2925217
Log data:
2018-09-11 00:00:01 -03 - [Warning-Duplicati.Library.Main.Operation.BackupHandler-SnapshotFailed]: Failed to create a snapshot: Alphaleonis.Win32.Vss.VssSnapshotSetInProgressException: The creation of a shadow copy is already in progress.
at Alphaleonis.Win32.Vss.VssBackupComponents.StartSnapshotSet()
at Duplicati.Library.Snapshots.WindowsSnapshot…ctor(IEnumerable1 sources, IDictionary2 options)
at Duplicati.Library.Snapshots.SnapshotUtility.CreateWindowsSnapshot(IEnumerable1 folders, Dictionary2 options)
at Duplicati.Library.Main.Operation.BackupHandler.GetSnapshot(String sources, Options options)
Alphaleonis.Win32.Vss.VssSnapshotSetInProgressException: The creation of a shadow copy is already in progress.
at Alphaleonis.Win32.Vss.VssBackupComponents.StartSnapshotSet()
at Duplicati.Library.Snapshots.WindowsSnapshot…ctor(IEnumerable1 sources, IDictionary2 options)
at Duplicati.Library.Snapshots.SnapshotUtility.CreateWindowsSnapshot(IEnumerable1 folders, Dictionary2 options)
at Duplicati.Library.Main.Operation.BackupHandler.GetSnapshot(String sources, Options options)

2

Do you have anything else running at 12am that may create a snapshot? Regularly scheduled shadow copy, or maybe another backup program? If two separate processes try to create a snapshot at close to the same time, the second will fail with this error message.

3

Hello
Very nice to know that this feature is on the way to duplicati.

This is a Virtual Machine, night is backed up from this VM, the hypervisor uses the Snapshot feature to perform this backup.
I’ll conduct more testing and see if this could be the cause.
Thank you.

4

It may be sufficient to just delay Duplicati’s schedule or the other backup schedule by just a few minutes. That way they won’t try to make the snapshot at exactly the same time.

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