Why does backup job not start?

1

If I reboot my machine and try to launch a newly created backup job then I always see these log entries:

Failed: The creation of a shadow copy is already in progress.
Details: Alphaleonis.Win32.Vss.VssSnapshotSetInProgressException: The creation of a shadow copy is already in progress.
bei Alphaleonis.Win32.Vss.VssBackupComponents.StartSnapshotSet()
bei Duplicati.Library.Snapshots.WindowsSnapshot…ctor(IEnumerable1 sources, IDictionary2 options)
bei Duplicati.Library.Snapshots.SnapshotUtility.CreateWindowsSnapshot(IEnumerable1 folders, Dictionary2 options)
bei Duplicati.Library.Main.Operation.BackupHandler.GetSnapshot(String sources, Options options)
bei Duplicati.Library.Main.Operation.BackupHandler.<RunAsync>d__19.MoveNext()
— Ende der Stapelüberwachung vom vorhergehenden Ort, an dem die Ausnahme ausgelöst wurde —
bei System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
bei CoCoL.ChannelExtensions.WaitForTaskOrThrow(Task task)
bei Duplicati.Library.Main.Controller.<>c__DisplayClass13_0.<Backup>b__0(BackupResults result)
bei Duplicati.Library.Main.Controller.RunAction[T](T result, String& paths, IFilter& filter, Action`1 method)

Log data:
2019-04-05 17:37:58 +02 - [Error-Duplicati.Library.Main.Operation.BackupHandler-FatalError]: Fatal error
Alphaleonis.Win32.Vss.VssSnapshotSetInProgressException: The creation of a shadow copy is already in progress.
bei Alphaleonis.Win32.Vss.VssBackupComponents.StartSnapshotSet()
bei Duplicati.Library.Snapshots.WindowsSnapshot…ctor(IEnumerable1 sources, IDictionary2 options)
bei Duplicati.Library.Snapshots.SnapshotUtility.CreateWindowsSnapshot(IEnumerable1 folders, Dictionary2 options)
bei Duplicati.Library.Main.Operation.BackupHandler.GetSnapshot(String sources, Options options)
bei Duplicati.Library.Main.Operation.BackupHandler.<RunAsync>d__19.MoveNext()

X-Laufwerk-duplicati-config(1).zip (829 Bytes)

I have uploaded the backup job as .zip - maybe one of the experts here is able to tell me what I am doing wrong …

Duplicati is running as a service under my user credentials - other backup jobs are working.

My guess is that the network share (source) causes the troubles but I have got all the privileges …

2

Are you trying to take VSS snapshots of a remote SMB share on a NAS? I see –snapshot-policy=Required. Does removing that option help? I wasn’t sure such a snapshot was possibly. It is, but may be uncommon.

VSS for SMB File Shares

SMB remote file protocol (including SMB 3.x)

Implemented by at least one vendor besides Microsoft

VssSnapshotSetInProgressException Class

Exception indicating that the creation of a shadow copy is in progress, and only one shadow copy creation operation can be in progress at one time. Either wait to try again or return with a failure.

Hyper-V-machine-backup not running on Windows Server 2016 is one where the message began at

Alphaleonis.Win32.Vss.VssUnexpectedProviderErrorException: The provider returned an unexpected error code.

then on second try went to

Alphaleonis.Win32.Vss.VssSnapshotSetInProgressException: The creation of a shadow copy is already in progress.

however it sounds like you jump right to the second error, otherwise I’d just theorize that snapshot began, but was invalid and didn’t end, thereby causing an “in progress error”… In any case, try not asking for it…

3

Yes that was what I tried …

I have now set snapshot-policy=off and the job started!

Thanks for your support - it seems it was a typical Newcomer failure … :grinning: