Backup error when taking backup

Support
1

Hi Team,

We are getting below error when backing up.

Failed: Unexpected difference in fileset version 66: 7/16/2023 1:00:00 AM (database id: 41), found 2482947 entries, but expected 2483244
Details: Duplicati.Library.Interface.UserInformationException: Unexpected difference in fileset version 66: 7/16/2023 1:00:00 AM (database id: 41), found 2482947 entries, but expected 2483244
at Duplicati.Library.Main.Database.LocalDatabase.VerifyConsistency(Int64 blocksize, Int64 hashsize, Boolean verifyfilelists, IDbTransaction transaction)
at Duplicati.Library.Main.Operation.Backup.BackupDatabase.<>c__DisplayClass34_0.b__0()
at Duplicati.Library.Main.Operation.Common.SingleRunner.<>c__DisplayClass3_0.b__0()
at Duplicati.Library.Main.Operation.Common.SingleRunner.d__21.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Duplicati.Library.Main.Operation.BackupHandler.<RunAsync>d__20.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at CoCoL.ChannelExtensions.WaitForTaskOrThrow(Task task) at Duplicati.Library.Main.Controller.<>c__DisplayClass14_0.<Backup>b__0(BackupResults result) at Duplicati.Library.Main.Controller.RunAction[T](T result, String[]& paths, IFilter& filter, Action1 method)

Log data:
2024-02-24 09:22:59 +02 - [Error-Duplicati.Library.Main.Operation.BackupHandler-FatalError]: Fatal error
Duplicati.Library.Interface.UserInformationException: Unexpected difference in fileset version 66: 7/16/2023 1:00:00 AM (database id: 41), found 2482947 entries, but expected 2483244
at Duplicati.Library.Main.Database.LocalDatabase.VerifyConsistency(Int64 blocksize, Int64 hashsize, Boolean verifyfilelists, IDbTransaction transaction)
at Duplicati.Library.Main.Operation.Backup.BackupDatabase.<>c__DisplayClass34_0.b__0()
at Duplicati.Library.Main.Operation.Common.SingleRunner.<>c__DisplayClass3_0.b__0()
at Duplicati.Library.Main.Operation.Common.SingleRunner.d__2`1.MoveNext()
— End of stack trace from previous location where exception was thrown —
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Duplicati.Library.Main.Operation.BackupHandler.d__20.MoveNext()

Thanks,
Shakeel

2

Welcome to the forum @Shakeelb

Does this backup happen on a regular schedule, for example at 1:00:00 AM?

What was the result of the one before the failed backup? Look at the job log,
especially in Compact Phase. What did it do? That’s sometimes the suspect.

If there’s no job log, check About → Show log → Stored for data near failure.

Any other known oddities, or clues to what might have made a sudden error?

Typically people don’t have extra logs around, but I’ll ask, just in case you do.

This issue gets technical to investigate, but there’s one enhancement around:

2.0.7.100_canary_2023-12-27

Report all filesets in error in VerifyConsistency, thanks @gpatel-fr

After getting initial data, we can decide if we want to go Canary at least awhile.

3

You can also look at <job> → Show log → Remote for when prior backup should have ended, e.g.

Feb 24, 2024 7:08 AM: get duplicati-b93017ccb088946c695f974f7fbfc95ae.dblock.zip.aes
Feb 24, 2024 7:08 AM: get duplicati-i2404ca250c1844e6bdb3759c1cb5580c.dindex.zip.aes
Feb 24, 2024 7:08 AM: get duplicati-20240223T120906Z.dlist.zip.aes
Feb 24, 2024 7:08 AM: list
Feb 24, 2024 7:07 AM: put duplicati-20240224T120503Z.dlist.zip.aes

is a normal end (reverse-chronological). At end of backup, it uploads a dlist saying what’s in it, then
Verifying backend files downloads a set of files to make sure they’re OK. If a backup fails early, logs potentially are rolled back in the database as part of trying to cleanly revert unfinished backup itself.

About → Show log → Stored will survive fail (so please look there), as will your log-file if you set up.