Post-Backup verification consistently fails

Support
1

Hi,

I’ve been trying to backup to a B2 Bucket and everything seems to go fine besides the post-upload verification stage. I’ve got 5 instances of the same pair of errors (one each day/backup). Here’s the most recent at the time of writing:

  1. 2025-09-09 02:14:07 +01 - [Error-Duplicati.Library.Main.Operation.TestHandler-FailedToProcessFile]: Failed to process file duplicati-bb43e19678a984582b4698e3e19a3bc5c.dblock.zip.aes IOException: Received an unexpected EOF or 0 bytes from the transport stream.
  2. 2025-09-09 02:14:07 +01 - [Error-Duplicati.Library.Main.Operation.TestHandler-Test results]: Verified 3 remote files with 1 problem(s)
Log 
            {
  "DeletedFiles": 2,
  "DeletedFolders": 0,
  "ModifiedFiles": 117,
  "ExaminedFiles": 27893,
  "OpenedFiles": 1475,
  "AddedFiles": 1358,
  "SizeOfModifiedFiles": 112589960,
  "SizeOfAddedFiles": 167489051,
  "SizeOfExaminedFiles": 38886976268,
  "SizeOfOpenedFiles": 280079019,
  "NotProcessedFiles": 0,
  "AddedFolders": 834,
  "TooLargeFiles": 0,
  "FilesWithError": 0,
  "ModifiedFolders": 0,
  "ModifiedSymlinks": 0,
  "AddedSymlinks": 0,
  "DeletedSymlinks": 0,
  "PartialBackup": false,
  "Dryrun": false,
  "MainOperation": "Backup",
  "CompactResults": null,
  "VacuumResults": null,
  "DeleteResults": {
    "DeletedSetsActualLength": 0,
    "DeletedSets": [],
    "Dryrun": false,
    "MainOperation": "Delete",
    "CompactResults": null,
    "ParsedResult": "Success",
    "Interrupted": false,
    "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
    "EndTime": "2025-09-09T01:01:54.1651252Z",
    "BeginTime": "2025-09-09T01:01:53.5099791Z",
    "Duration": "00:00:00.6551461",
    "MessagesActualLength": 0,
    "WarningsActualLength": 0,
    "ErrorsActualLength": 0,
    "Messages": null,
    "Warnings": null,
    "Errors": null,
    "BackendStatistics": {
      "RemoteCalls": 31,
      "BytesUploaded": 175842069,
      "BytesDownloaded": 3245642,
      "FilesUploaded": 9,
      "FilesDownloaded": 2,
      "FilesDeleted": 0,
      "FoldersCreated": 0,
      "RetryAttempts": 17,
      "UnknownFileSize": 0,
      "UnknownFileCount": 0,
      "KnownFileCount": 1498,
      "KnownFileSize": 38481209698,
      "LastBackupDate": "2025-09-09T02:00:00+01:00",
      "BackupListCount": 4,
      "TotalQuotaSpace": 0,
      "FreeQuotaSpace": 0,
      "AssignedQuotaSpace": -1,
      "ReportedQuotaError": false,
      "ReportedQuotaWarning": false,
      "MainOperation": "Backup",
      "ParsedResult": "Success",
      "Interrupted": false,
      "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
      "EndTime": "0001-01-01T00:00:00",
      "BeginTime": "2025-09-09T01:00:00.1610489Z",
      "Duration": "00:00:00",
      "MessagesActualLength": 0,
      "WarningsActualLength": 0,
      "ErrorsActualLength": 0,
      "Messages": null,
      "Warnings": null,
      "Errors": null
    }
  },
  "RepairResults": null,
  "TestResults": {
    "MainOperation": "Test",
    "VerificationsActualLength": 3,
    "Verifications": [
      {
        "Key": "duplicati-20250909T010000Z.dlist.zip.aes",
        "Value": []
      },
      {
        "Key": "duplicati-i4d4825bac23d477ea7c280f50ace1995.dindex.zip.aes",
        "Value": []
      },
      {
        "Key": "duplicati-bb43e19678a984582b4698e3e19a3bc5c.dblock.zip.aes",
        "Value": [
          {
            "Key": "Error",
            "Value": "Received an unexpected EOF or 0 bytes from the transport stream."
          }
        ]
      }
    ],
    "ParsedResult": "Success",
    "Interrupted": false,
    "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
    "EndTime": "2025-09-09T01:14:07.880471Z",
    "BeginTime": "2025-09-09T01:01:56.1251527Z",
    "Duration": "00:12:11.7553183",
    "MessagesActualLength": 0,
    "WarningsActualLength": 0,
    "ErrorsActualLength": 0,
    "Messages": null,
    "Warnings": null,
    "Errors": null,
    "BackendStatistics": {
      "RemoteCalls": 31,
      "BytesUploaded": 175842069,
      "BytesDownloaded": 3245642,
      "FilesUploaded": 9,
      "FilesDownloaded": 2,
      "FilesDeleted": 0,
      "FoldersCreated": 0,
      "RetryAttempts": 17,
      "UnknownFileSize": 0,
      "UnknownFileCount": 0,
      "KnownFileCount": 1498,
      "KnownFileSize": 38481209698,
      "LastBackupDate": "2025-09-09T02:00:00+01:00",
      "BackupListCount": 4,
      "TotalQuotaSpace": 0,
      "FreeQuotaSpace": 0,
      "AssignedQuotaSpace": -1,
      "ReportedQuotaError": false,
      "ReportedQuotaWarning": false,
      "MainOperation": "Backup",
      "ParsedResult": "Success",
      "Interrupted": false,
      "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
      "EndTime": "0001-01-01T00:00:00",
      "BeginTime": "2025-09-09T01:00:00.1610489Z",
      "Duration": "00:00:00",
      "MessagesActualLength": 0,
      "WarningsActualLength": 0,
      "ErrorsActualLength": 0,
      "Messages": null,
      "Warnings": null,
      "Errors": null
    }
  },
  "ParsedResult": "Error",
  "Interrupted": false,
  "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
  "EndTime": "2025-09-09T01:14:07.9227126Z",
  "BeginTime": "2025-09-09T01:00:00.1610087Z",
  "Duration": "00:14:07.7617039",
  "MessagesActualLength": 81,
  "WarningsActualLength": 0,
  "ErrorsActualLength": 2,
  "Messages": [
    "2025-09-09 02:00:00 +01 - [Information-Duplicati.Library.Main.Controller-StartingOperation]: The operation Backup has started",
    "2025-09-09 02:00:01 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: List - Started:  ()",
    "2025-09-09 02:00:03 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: List - Completed:  (1.45 KB)",
    "2025-09-09 02:00:14 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-b65d8caac4c8144da81cb8a06a76b7ed7.dblock.zip.aes (49.71 MB)",
    "2025-09-09 02:00:14 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-b2eabac39cbb4439e9f6c09053834805a.dblock.zip.aes (49.53 MB)",
    "2025-09-09 02:00:34 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Completed: duplicati-b65d8caac4c8144da81cb8a06a76b7ed7.dblock.zip.aes (49.71 MB)",
    "2025-09-09 02:00:34 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-i3e1aeec2ca234e629f647547cc4242eb.dindex.zip.aes (17.58 KB)",
    "2025-09-09 02:00:34 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Retrying: duplicati-i3e1aeec2ca234e629f647547cc4242eb.dindex.zip.aes (17.58 KB)",
    "2025-09-09 02:00:41 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-b7c59a126ee054ce8ac28aa7df4f74a50.dblock.zip.aes (49.25 MB)",
    "2025-09-09 02:00:44 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Rename: duplicati-i3e1aeec2ca234e629f647547cc4242eb.dindex.zip.aes (17.58 KB)",
    "2025-09-09 02:00:44 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Rename: duplicati-ied9ba38491a341bea7a2ffb4f86ee829.dindex.zip.aes (17.58 KB)",
    "2025-09-09 02:00:44 +01 - [Information-Duplicati.Library.Main.Operation.Backup.BackendUploader-RenameRemoteTargetFile]: Renaming \"duplicati-i3e1aeec2ca234e629f647547cc4242eb.dindex.zip.aes\" to \"duplicati-ied9ba38491a341bea7a2ffb4f86ee829.dindex.zip.aes\"",
    "2025-09-09 02:00:44 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-ied9ba38491a341bea7a2ffb4f86ee829.dindex.zip.aes (17.58 KB)",
    "2025-09-09 02:00:45 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Retrying: duplicati-b2eabac39cbb4439e9f6c09053834805a.dblock.zip.aes (49.53 MB)",
    "2025-09-09 02:00:48 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Completed: duplicati-ied9ba38491a341bea7a2ffb4f86ee829.dindex.zip.aes (17.58 KB)",
    "2025-09-09 02:00:55 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-b322ab5e9a88f4498a8f65ccc2bfbc093.dblock.zip.aes (15.96 MB)",
    "2025-09-09 02:00:55 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Rename: duplicati-b2eabac39cbb4439e9f6c09053834805a.dblock.zip.aes (49.53 MB)",
    "2025-09-09 02:00:55 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Rename: duplicati-bc34ed652998d48529923f8f6ffccfe2e.dblock.zip.aes (49.53 MB)",
    "2025-09-09 02:00:55 +01 - [Information-Duplicati.Library.Main.Operation.Backup.BackendUploader-RenameRemoteTargetFile]: Renaming \"duplicati-b2eabac39cbb4439e9f6c09053834805a.dblock.zip.aes\" to \"duplicati-bc34ed652998d48529923f8f6ffccfe2e.dblock.zip.aes\"",
    "2025-09-09 02:00:56 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-bc34ed652998d48529923f8f6ffccfe2e.dblock.zip.aes (49.53 MB)"
  ],
  "Warnings": [],
  "Errors": [
    "2025-09-09 02:14:07 +01 - [Error-Duplicati.Library.Main.Operation.TestHandler-FailedToProcessFile]: Failed to process file duplicati-bb43e19678a984582b4698e3e19a3bc5c.dblock.zip.aes\nIOException: Received an unexpected EOF or 0 bytes from the transport stream.",
    "2025-09-09 02:14:07 +01 - [Error-Duplicati.Library.Main.Operation.TestHandler-Test results]: Verified 3 remote files with 1 problem(s)"
  ],
  "BackendStatistics": {
    "RemoteCalls": 31,
    "BytesUploaded": 175842069,
    "BytesDownloaded": 3245642,
    "FilesUploaded": 9,
    "FilesDownloaded": 2,
    "FilesDeleted": 0,
    "FoldersCreated": 0,
    "RetryAttempts": 17,
    "UnknownFileSize": 0,
    "UnknownFileCount": 0,
    "KnownFileCount": 1498,
    "KnownFileSize": 38481209698,
    "LastBackupDate": "2025-09-09T02:00:00+01:00",
    "BackupListCount": 4,
    "TotalQuotaSpace": 0,
    "FreeQuotaSpace": 0,
    "AssignedQuotaSpace": -1,
    "ReportedQuotaError": false,
    "ReportedQuotaWarning": false,
    "MainOperation": "Backup",
    "ParsedResult": "Success",
    "Interrupted": false,
    "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
    "EndTime": "0001-01-01T00:00:00",
    "BeginTime": "2025-09-09T01:00:00.1610489Z",
    "Duration": "00:00:00",
    "MessagesActualLength": 0,
    "WarningsActualLength": 0,
    "ErrorsActualLength": 0,
    "Messages": null,
    "Warnings": null,
    "Errors": null
  }
}

It seems to be a different block each time, and I’m happy to provide logs for previous runs - I just didn’t want to clutter this first post up.

And a manual verification runs fine:

Manual Test log 
            {
  "MainOperation": "Test",
  "VerificationsActualLength": 3,
  "Verifications": [
    {
      "Key": "duplicati-20250907T010000Z.dlist.zip.aes",
      "Value": []
    },
    {
      "Key": "duplicati-i2ec4e501dadb4011999f586fc7a16084.dindex.zip.aes",
      "Value": []
    },
    {
      "Key": "duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes",
      "Value": []
    }
  ],
  "ParsedResult": "Success",
  "Interrupted": false,
  "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
  "EndTime": "2025-09-09T07:59:53.2445473Z",
  "BeginTime": "2025-09-09T07:55:10.1845186Z",
  "Duration": "00:04:43.0600287",
  "MessagesActualLength": 18,
  "WarningsActualLength": 0,
  "ErrorsActualLength": 0,
  "Messages": [
    "2025-09-09 08:55:10 +01 - [Information-Duplicati.Library.Main.Controller-StartingOperation]: The operation Test has started",
    "2025-09-09 08:55:11 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: List - Started:  ()",
    "2025-09-09 08:55:14 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: List - Completed:  (1.46 KB)",
    "2025-09-09 08:55:14 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Started: duplicati-20250907T010000Z.dlist.zip.aes (2.93 MB)",
    "2025-09-09 08:55:16 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Completed: duplicati-20250907T010000Z.dlist.zip.aes (2.93 MB)",
    "2025-09-09 08:55:16 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Started: duplicati-i2ec4e501dadb4011999f586fc7a16084.dindex.zip.aes (2.54 KB)",
    "2025-09-09 08:55:16 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Completed: duplicati-i2ec4e501dadb4011999f586fc7a16084.dindex.zip.aes (2.54 KB)",
    "2025-09-09 08:55:17 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Started: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:56:07 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Retrying: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:56:17 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Started: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:57:02 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Retrying: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:57:12 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Started: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:58:02 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Retrying: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:58:12 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Started: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:58:59 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Retrying: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:59:09 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Started: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:59:53 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Get - Completed: duplicati-b1831fde37e234b53840cf0ad53d1d545.dblock.zip.aes (49.01 MB)",
    "2025-09-09 08:59:53 +01 - [Information-Duplicati.Library.Main.Operation.TestHandler-Test results]: Successfully verified 3 remote files"
  ],
  "Warnings": [],
  "Errors": [],
  "BackendStatistics": {
    "RemoteCalls": 8,
    "BytesUploaded": 0,
    "BytesDownloaded": 54469607,
    "FilesUploaded": 0,
    "FilesDownloaded": 3,
    "FilesDeleted": 0,
    "FoldersCreated": 0,
    "RetryAttempts": 4,
    "UnknownFileSize": 0,
    "UnknownFileCount": 0,
    "KnownFileCount": 1498,
    "KnownFileSize": 38481209698,
    "LastBackupDate": "2025-09-09T02:00:00+01:00",
    "BackupListCount": 4,
    "TotalQuotaSpace": 0,
    "FreeQuotaSpace": 0,
    "AssignedQuotaSpace": -1,
    "ReportedQuotaError": false,
    "ReportedQuotaWarning": false,
    "MainOperation": "Test",
    "ParsedResult": "Success",
    "Interrupted": false,
    "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
    "EndTime": "0001-01-01T00:00:00",
    "BeginTime": "2025-09-09T07:55:10.1845271Z",
    "Duration": "00:00:00",
    "MessagesActualLength": 0,
    "WarningsActualLength": 0,
    "ErrorsActualLength": 0,
    "Messages": null,
    "Warnings": null,
    "Errors": null
  }
}

What’s odd to me is that I’m running an identical backup (same source, at least), but instead of a B2 Bucket, this is going to Google Drive. This gdrive backup runs with no errors, so there’s presumably no issue with post-upload verification.

The most recent log of my equivalent gdrive backup 
            {
  "DeletedFiles": 1,
  "DeletedFolders": 0,
  "ModifiedFiles": 117,
  "ExaminedFiles": 27893,
  "OpenedFiles": 1474,
  "AddedFiles": 1357,
  "SizeOfModifiedFiles": 112589960,
  "SizeOfAddedFiles": 118707369,
  "SizeOfExaminedFiles": 38886976268,
  "SizeOfOpenedFiles": 231297337,
  "NotProcessedFiles": 0,
  "AddedFolders": 834,
  "TooLargeFiles": 0,
  "FilesWithError": 0,
  "ModifiedFolders": 0,
  "ModifiedSymlinks": 0,
  "AddedSymlinks": 0,
  "DeletedSymlinks": 0,
  "PartialBackup": false,
  "Dryrun": false,
  "MainOperation": "Backup",
  "CompactResults": {
    "DeletedFileCount": 0,
    "DownloadedFileCount": 0,
    "UploadedFileCount": 0,
    "DeletedFileSize": 0,
    "DownloadedFileSize": 0,
    "UploadedFileSize": 0,
    "Dryrun": false,
    "VacuumResults": null,
    "MainOperation": "Compact",
    "ParsedResult": "Success",
    "Interrupted": false,
    "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
    "EndTime": "2025-09-09T01:15:59.8535117Z",
    "BeginTime": "2025-09-09T01:15:59.31883Z",
    "Duration": "00:00:00.5346817",
    "MessagesActualLength": 0,
    "WarningsActualLength": 0,
    "ErrorsActualLength": 0,
    "Messages": null,
    "Warnings": null,
    "Errors": null,
    "BackendStatistics": {
      "RemoteCalls": 13,
      "BytesUploaded": 157460155,
      "BytesDownloaded": 54935895,
      "FilesUploaded": 7,
      "FilesDownloaded": 3,
      "FilesDeleted": 1,
      "FoldersCreated": 0,
      "RetryAttempts": 0,
      "UnknownFileSize": 0,
      "UnknownFileCount": 0,
      "KnownFileCount": 1497,
      "KnownFileSize": 38475362341,
      "LastBackupDate": "2025-09-09T02:14:08+01:00",
      "BackupListCount": 3,
      "TotalQuotaSpace": 107374182400,
      "FreeQuotaSpace": 63789788866,
      "AssignedQuotaSpace": -1,
      "ReportedQuotaError": false,
      "ReportedQuotaWarning": false,
      "MainOperation": "Backup",
      "ParsedResult": "Success",
      "Interrupted": false,
      "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
      "EndTime": "0001-01-01T00:00:00",
      "BeginTime": "2025-09-09T01:14:08.4051386Z",
      "Duration": "00:00:00",
      "MessagesActualLength": 0,
      "WarningsActualLength": 0,
      "ErrorsActualLength": 0,
      "Messages": null,
      "Warnings": null,
      "Errors": null
    }
  },
  "VacuumResults": null,
  "DeleteResults": {
    "DeletedSetsActualLength": 1,
    "DeletedSets": [
      {
        "Item1": 1,
        "Item2": "2025-09-08T02:04:34+01:00"
      }
    ],
    "Dryrun": false,
    "MainOperation": "Delete",
    "CompactResults": {
      "DeletedFileCount": 0,
      "DownloadedFileCount": 0,
      "UploadedFileCount": 0,
      "DeletedFileSize": 0,
      "DownloadedFileSize": 0,
      "UploadedFileSize": 0,
      "Dryrun": false,
      "VacuumResults": null,
      "MainOperation": "Compact",
      "ParsedResult": "Success",
      "Interrupted": false,
      "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
      "EndTime": "2025-09-09T01:15:59.8535117Z",
      "BeginTime": "2025-09-09T01:15:59.31883Z",
      "Duration": "00:00:00.5346817",
      "MessagesActualLength": 0,
      "WarningsActualLength": 0,
      "ErrorsActualLength": 0,
      "Messages": null,
      "Warnings": null,
      "Errors": null,
      "BackendStatistics": {
        "RemoteCalls": 13,
        "BytesUploaded": 157460155,
        "BytesDownloaded": 54935895,
        "FilesUploaded": 7,
        "FilesDownloaded": 3,
        "FilesDeleted": 1,
        "FoldersCreated": 0,
        "RetryAttempts": 0,
        "UnknownFileSize": 0,
        "UnknownFileCount": 0,
        "KnownFileCount": 1497,
        "KnownFileSize": 38475362341,
        "LastBackupDate": "2025-09-09T02:14:08+01:00",
        "BackupListCount": 3,
        "TotalQuotaSpace": 107374182400,
        "FreeQuotaSpace": 63789788866,
        "AssignedQuotaSpace": -1,
        "ReportedQuotaError": false,
        "ReportedQuotaWarning": false,
        "MainOperation": "Backup",
        "ParsedResult": "Success",
        "Interrupted": false,
        "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
        "EndTime": "0001-01-01T00:00:00",
        "BeginTime": "2025-09-09T01:14:08.4051386Z",
        "Duration": "00:00:00",
        "MessagesActualLength": 0,
        "WarningsActualLength": 0,
        "ErrorsActualLength": 0,
        "Messages": null,
        "Warnings": null,
        "Errors": null
      }
    },
    "ParsedResult": "Success",
    "Interrupted": false,
    "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
    "EndTime": "2025-09-09T01:15:59.8535186Z",
    "BeginTime": "2025-09-09T01:15:57.8219145Z",
    "Duration": "00:00:02.0316041",
    "MessagesActualLength": 0,
    "WarningsActualLength": 0,
    "ErrorsActualLength": 0,
    "Messages": null,
    "Warnings": null,
    "Errors": null,
    "BackendStatistics": {
      "RemoteCalls": 13,
      "BytesUploaded": 157460155,
      "BytesDownloaded": 54935895,
      "FilesUploaded": 7,
      "FilesDownloaded": 3,
      "FilesDeleted": 1,
      "FoldersCreated": 0,
      "RetryAttempts": 0,
      "UnknownFileSize": 0,
      "UnknownFileCount": 0,
      "KnownFileCount": 1497,
      "KnownFileSize": 38475362341,
      "LastBackupDate": "2025-09-09T02:14:08+01:00",
      "BackupListCount": 3,
      "TotalQuotaSpace": 107374182400,
      "FreeQuotaSpace": 63789788866,
      "AssignedQuotaSpace": -1,
      "ReportedQuotaError": false,
      "ReportedQuotaWarning": false,
      "MainOperation": "Backup",
      "ParsedResult": "Success",
      "Interrupted": false,
      "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
      "EndTime": "0001-01-01T00:00:00",
      "BeginTime": "2025-09-09T01:14:08.4051386Z",
      "Duration": "00:00:00",
      "MessagesActualLength": 0,
      "WarningsActualLength": 0,
      "ErrorsActualLength": 0,
      "Messages": null,
      "Warnings": null,
      "Errors": null
    }
  },
  "RepairResults": null,
  "TestResults": {
    "MainOperation": "Test",
    "VerificationsActualLength": 3,
    "Verifications": [
      {
        "Key": "duplicati-20250909T011408Z.dlist.zip.aes",
        "Value": []
      },
      {
        "Key": "duplicati-i2a906781ff9f4f40a4d2e2e3194d7c30.dindex.zip.aes",
        "Value": []
      },
      {
        "Key": "duplicati-b2ccec1762c9e411fb0659060f4ee7e43.dblock.zip.aes",
        "Value": []
      }
    ],
    "ParsedResult": "Success",
    "Interrupted": false,
    "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
    "EndTime": "2025-09-09T01:17:20.9813527Z",
    "BeginTime": "2025-09-09T01:16:15.0523187Z",
    "Duration": "00:01:05.9290340",
    "MessagesActualLength": 0,
    "WarningsActualLength": 0,
    "ErrorsActualLength": 0,
    "Messages": null,
    "Warnings": null,
    "Errors": null,
    "BackendStatistics": {
      "RemoteCalls": 13,
      "BytesUploaded": 157460155,
      "BytesDownloaded": 54935895,
      "FilesUploaded": 7,
      "FilesDownloaded": 3,
      "FilesDeleted": 1,
      "FoldersCreated": 0,
      "RetryAttempts": 0,
      "UnknownFileSize": 0,
      "UnknownFileCount": 0,
      "KnownFileCount": 1497,
      "KnownFileSize": 38475362341,
      "LastBackupDate": "2025-09-09T02:14:08+01:00",
      "BackupListCount": 3,
      "TotalQuotaSpace": 107374182400,
      "FreeQuotaSpace": 63789788866,
      "AssignedQuotaSpace": -1,
      "ReportedQuotaError": false,
      "ReportedQuotaWarning": false,
      "MainOperation": "Backup",
      "ParsedResult": "Success",
      "Interrupted": false,
      "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
      "EndTime": "0001-01-01T00:00:00",
      "BeginTime": "2025-09-09T01:14:08.4051386Z",
      "Duration": "00:00:00",
      "MessagesActualLength": 0,
      "WarningsActualLength": 0,
      "ErrorsActualLength": 0,
      "Messages": null,
      "Warnings": null,
      "Errors": null
    }
  },
  "ParsedResult": "Success",
  "Interrupted": false,
  "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
  "EndTime": "2025-09-09T01:17:20.9908094Z",
  "BeginTime": "2025-09-09T01:14:08.4051232Z",
  "Duration": "00:03:12.5856862",
  "MessagesActualLength": 36,
  "WarningsActualLength": 0,
  "ErrorsActualLength": 0,
  "Messages": [
    "2025-09-09 02:14:08 +01 - [Information-Duplicati.Library.Main.Controller-StartingOperation]: The operation Backup has started",
    "2025-09-09 02:14:09 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: List - Started:  ()",
    "2025-09-09 02:14:26 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: List - Completed:  (1.46 KB)",
    "2025-09-09 02:14:38 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-b5ce973f96be74c07aa2b1c1e2458d42f.dblock.zip.aes (49.71 MB)",
    "2025-09-09 02:14:40 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-b1b7749a1a76846b6ae4e468e3838884d.dblock.zip.aes (49.03 MB)",
    "2025-09-09 02:15:11 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Completed: duplicati-b5ce973f96be74c07aa2b1c1e2458d42f.dblock.zip.aes (49.71 MB)",
    "2025-09-09 02:15:11 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-i6b10dd81838f46e0b41b073af68391b3.dindex.zip.aes (17.62 KB)",
    "2025-09-09 02:15:13 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Completed: duplicati-i6b10dd81838f46e0b41b073af68391b3.dindex.zip.aes (17.62 KB)",
    "2025-09-09 02:15:15 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Completed: duplicati-b1b7749a1a76846b6ae4e468e3838884d.dblock.zip.aes (49.03 MB)",
    "2025-09-09 02:15:15 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-i0cbc51e8aa844e0e88b0557039dc9000.dindex.zip.aes (9.18 KB)",
    "2025-09-09 02:15:23 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Completed: duplicati-i0cbc51e8aa844e0e88b0557039dc9000.dindex.zip.aes (9.18 KB)",
    "2025-09-09 02:15:24 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-b2c632a19059c4db3a111588e44fb3639.dblock.zip.aes (48.18 MB)",
    "2025-09-09 02:15:39 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Completed: duplicati-b2c632a19059c4db3a111588e44fb3639.dblock.zip.aes (48.18 MB)",
    "2025-09-09 02:15:39 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-i2b5700f157d94175b26e89320ba5c497.dindex.zip.aes (128.29 KB)",
    "2025-09-09 02:15:40 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Completed: duplicati-i2b5700f157d94175b26e89320ba5c497.dindex.zip.aes (128.29 KB)",
    "2025-09-09 02:15:41 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Started: duplicati-20250909T011408Z.dlist.zip.aes (3.09 MB)",
    "2025-09-09 02:15:57 +01 - [Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: Put - Completed: duplicati-20250909T011408Z.dlist.zip.aes (3.09 MB)",
    "2025-09-09 02:15:57 +01 - [Information-Duplicati.Library.Main.Operation.DeleteHandler:RetentionPolicy-StartCheck]: Start checking if backups can be removed",
    "2025-09-09 02:15:57 +01 - [Information-Duplicati.Library.Main.Operation.DeleteHandler:RetentionPolicy-FramesAndIntervals]: Time frames and intervals pairs: 7.00:00:00 / 1.00:00:00, 28.00:00:00 / 7.00:00:00, 365.00:00:00 / 31.00:00:00",
    "2025-09-09 02:15:57 +01 - [Information-Duplicati.Library.Main.Operation.DeleteHandler:RetentionPolicy-BackupList]: Backups to consider: 09/08/2025 02:04:34, 09/07/2025 02:05:17, 09/05/2025 18:42:55"
  ],
  "Warnings": [],
  "Errors": [],
  "BackendStatistics": {
    "RemoteCalls": 13,
    "BytesUploaded": 157460155,
    "BytesDownloaded": 54935895,
    "FilesUploaded": 7,
    "FilesDownloaded": 3,
    "FilesDeleted": 1,
    "FoldersCreated": 0,
    "RetryAttempts": 0,
    "UnknownFileSize": 0,
    "UnknownFileCount": 0,
    "KnownFileCount": 1497,
    "KnownFileSize": 38475362341,
    "LastBackupDate": "2025-09-09T02:14:08+01:00",
    "BackupListCount": 3,
    "TotalQuotaSpace": 107374182400,
    "FreeQuotaSpace": 63789788866,
    "AssignedQuotaSpace": -1,
    "ReportedQuotaError": false,
    "ReportedQuotaWarning": false,
    "MainOperation": "Backup",
    "ParsedResult": "Success",
    "Interrupted": false,
    "Version": "2.1.0.5 (2.1.0.5_stable_2025-03-04)",
    "EndTime": "0001-01-01T00:00:00",
    "BeginTime": "2025-09-09T01:14:08.4051386Z",
    "Duration": "00:00:00",
    "MessagesActualLength": 0,
    "WarningsActualLength": 0,
    "ErrorsActualLength": 0,
    "Messages": null,
    "Warnings": null,
    "Errors": null
  }
}

Sorry if this is a solved issue, but I couldn’t find a similar issue on the forum besides this dead end: OneDrive backup contantly failing with "Failed to process file" error - #5 by ts678

Any and all help is welcome. I’ve only been running Duplicati for about a week, and am new to this space and to using B2, so please don’t hesitate to point out if that IOException could be caused by a newbie error! I’m crossing my fingers this is the case.

2

I’m starting to think this is a speed/network issue. Has anyone else encountered EOF related errors using B2 Storage?

I’ve found a couple of examples of rclone users running into this:

https://www.reddit.com/r/backblaze/comments/blqk39/issues_downloading_files_from_b2/

3

I’ve opened a support ticket with Backblaze, and will update here when I hear back.

4

Welcome to the forum @sudorand

It hardly counts since it’s so rare for me (and networks do odd things sometimes) but

Log data:
2023-11-30 07:25:00 -05 - [Error-Duplicati.Library.Main.Operation.TestHandler-FailedToProcessFile]: Failed to process file duplicati-b3587c0b3b216416eb5749e3e2f3203bf.dblock.zip.aes
System.IO.IOException: Received an unexpected EOF or 0 bytes from the transport stream.
   at Duplicati.Library.Main.BackendManager.GetForTesting(String remotename, Int64 size, String hash)
   at Duplicati.Library.Main.Operation.TestHandler.DoRun(Int64 samples, LocalTestDatabase db, BackendManager backend)

is in my Gmail, for “Received an unexpected EOF or 0 bytes from the transport stream.”
Searching for that in Google shows AI Overview of some possible causes and solutions.

Can’t totally agree.

compared to

I wouldn’t call it fine (it survived only by retries), but it did better than the run that failed.
number-of-retries (and related settings) can be changed, but it’s better to fix cause.

One statistic doesn’t break down retries on upload and download, and it doesn’t show distribution. To actually fail, one needs to exceed retries for a given operation (in a row).

Seeing exact non-fatal retry spots can be done, e.g. if you option up custom log-file.

It’s a sample, weighted towards files that were verified fewer times (so often new ones).

Advanced options backup-test-samples and backup-test-percentage set the size.

The TEST command can do manual runs. Easier than true CLI is in GUI Commandline.

In true CLI, you can use the below with destination URL from Export As Command-line.

BackendTool is good if you want full control to specify the operation and the file it uses.

BackendTester is good for an automated test. Modify the URL to test in an empty folder.

5

My backblaze support ticket has concluded with the following:

There is something causing an inconsistency between local and remote files; this is why we see the end of file error.

Basically, we have a file that is x bytes in size, while you have one that is y bytes. When comparing the two, Duplicati sees the difference in size and throws an error.

The only other possibility is packet loss from your network path to Backblaze.

I hope this clarifies things, and I apologize for the situation.

It seems fairly conclusively to be a networking issue. Adjusting number of retries and timeouts has made no change besides making backups take longer to run.

At least with my current ISP and Backblaze’s current NaaS provider, GTT, there doesn’t seem to be any hope in getting this resolved. So I’m giving up on B2 and probably cloud backups in general.

They had previously implied the issue to be from Duplicati’s end which I doubt looking at the traceroute they requested I do and how much loss there is entering their NaaS provider.

mtr from my box to backblaze, as requested by them in the ticket
mtr from my box to backblaze, as requested by them in the ticket1081×327 10.4 KB

Thanks @ts678 for your reply and troubleshooting suggestions, this was helpful for trying to understand the problem at the start.

6

Agree. I see the same problem from time to time.

When I change my default internet provider, the problem goes away.

Edit: possible workaround (not tested enough though) - use Cloudflare’s WARP or ZeroTrust, that allows to partially bypass ISP’s routing.