Invalid Header Marker - File length invalid

Support
1

Hello,

since a couple of days one of my laptops has been showing some errors after finishing a backup.
I backup files from a laptop to a share on my unRaid Server. Duplicati has no special setup. Just the selected files to be backed up to the share on the unRaid server. The file size of the backup files is set to 100MB.
In the error log it shows me two errors and tells me to run a Repair. When I do that, the next time the Backup runs still shows me the same errors. From the log I see this:

Warnings 2

  • 2022-03-06 20:24:59 +01 - [Warning-Duplicati.Library.Main.Operation.FilelistProcessor-MissingRemoteHash]: remote file duplicati-b4f4cb23f4a75457980e664e2de689dc7.dblock.zip.aes is listed as Uploaded with size 16777216 but should be 111048477, please verify the sha256 hash “j7XmkySc1kt0Uoh66Ae7hZlB/vBysovras5cZI7kJI8=”
  • 2022-03-06 20:24:59 +01 - [Warning-Duplicati.Library.Main.Operation.FilelistProcessor-MissingRemoteHash]: remote file duplicati-b6bfc48c5c27d4db7b06cfce8a7bf3f4e.dblock.zip.aes is listed as Uploaded with size 0 but should be 642109, please verify the sha256 hash “OJ3/7qFyvEwZYLsriTsWK+/HzSKrTSk3WkVnKu1TwxM=”

Errors 2

  • 2022-03-06 20:26:07 +01 - [Error-Duplicati.Library.Main.Operation.RepairHandler-RemoteFileVerificationError]: Failed to perform verification for file: duplicati-b4f4cb23f4a75457980e664e2de689dc7.dblock.zip.aes, please run verify; message: File length is invalid
  • 2022-03-06 20:26:47 +01 - [Error-Duplicati.Library.Main.Operation.RepairHandler-RemoteFileVerificationError]: Failed to perform verification for file: duplicati-b6bfc48c5c27d4db7b06cfce8a7bf3f4e.dblock.zip.aes, please run verify; message: Invalid header marker

Would anyone be able to tell me what this means and how I can resolve it? I tried running Repair a few times and restarting the backup job.
I am running version 2.0.6.3_beta_2021-06-17.
Please let me know if I can provide more information.

Thank you very much!!

Odom

2

Welcome to the forum @Odom

The warnings are telling you that the file listing it sees don’t match what its database thinks it has written. Getting a listing at either size is suspect, because the first is oddly even in hexadecimal, and second is 0.

Are you able to confirm the wrong sizes, viewed directly on the server, getting SMB work out of the way?

For reasons that nobody has been able to debug (maybe you will be the first), Duplicati files written over SMB sometimes get truncated, and round sizes such as 16777216 (hexadecimal 1000000) are common which suggests it’s a filesystem or SMB issue. Duplicati doesn’t do SMB itself. It treats it like any OS file.

What OS is this? If Windows, Sysinternals Process Monitor might show low-level activity inside Windows, however what it actually has been doing on systems where we need it is – not work. Possibly yours will…

Quick way to try to bypass SMB problems is to use something else, e.g. SFTP, but debug would be good if it gets anywhere (but it might not). There are also client and maybe server options you could try testing.