Flamenco-Management/FLAMENCO_BUG_REPORT.md

System Information Operating System(s): Win11 25h2

Flamenco Version Is Broken: 3.8.2 Worked OK: unknown

When Flamenco is ran from a Windows machine, with the shared-storage set to an SMB share, the symlinks (Windows reparse points) created by Shaman appear to be either completely useless at worst, or context dependent at best.

I don't know if this is a bug, or if I'm doing something wrong. But I can't get a windows system to create proper Windows Reparse points on an SMB share. And I'm not the only one in recent history who has struggled to get Shaman to work with Windows and Samba.

1. Download and configure Flamenco
2. Configure the security policy as instructed in the documentation
3. Enable symlinks on the (Linux) machine hosting your SMB share, as instructed in the documentation
4. Set shaman: enabled: true.
5. Set shared_storage_path. I was originally hosting the files on a TrueNAS SMB share (mapped to F:). Testing it with a local drive (T:\Flamenco) results with the intended behavior.
6. Submit job

The symlinks created within jobs will not be universally accessible by Windows. All Windows workers (I have only tested Windows) will fail:

2026-01-08T15:51:58-07:00 Task assigned to worker i9kf (3690a968-f7ee-49d5-adb7-76154761d435)
2026-01-08T15:51:58-07:00 task changed status queued -> active
going to run:

    'F:\software\Blender\blender.exe' -b -y --gpu-backend opengl 'F:\jobs/SSD_2B/SSD_2B.flamenco.blend' --python-expr '
import bpy

cycles_prefs = bpy.context.preferences.addons['"'"'cycles'"'"'].preferences
cycles_prefs.compute_device_type = '"'"'OPTIX'"'"'
for dev in cycles_prefs.get_devices_for_type('"'"'OPTIX'"'"'):
    dev.use = (dev.type != '"'"'CPU'"'"')
' --python-expr 'import bpy; bpy.context.scene.cycles.device = '"'"'GPU'"'"'' --render-output 'F:/renders/SSD_2B/2026-01-08_151057/######' --render-format PNG --render-frame 0..15

pid=32124 > 00:10.047  reports          | ERROR File format is not supported in file "F:\jobs\SSD_2B\SSD_2B.flamenco.blend"
pid=32124 > Blender 5.0.1 (hash a3db93c5b259 built 2025-12-16 01:32:30)
pid=32124 > Cannot read ARP prefs
pid=32124 > Update armature presets...
pid=32124 > animation_layers_updater addon: Verbose is enabled
pid=32124 > animation_layers_updater addon: Read in JSON settings from file
pid=32124 > 
pid=32124 > Blender quit
Failed: command exited abnormally with code 1
2026-01-08T15:52:11-07:00 Task failed by 1 worker, Manager will mark it as soft failure. 2 more failures will cause hard failure.
2026-01-08T15:52:11-07:00 task changed status active -> soft-failed

Examining the jobfiles reveals the issue. The file is detected as .symlink type. However, the symlink points to the proper Shaman Blob.

If you right click and edit the symlink in notepad, it opens the blob: A proper blendfile with gzip compression.

When opened in VSCode, it opens blank.

When copied to another folder, it copies a blank file.

If you open the symlink in blender, the error is replicated: File format is not supported in file "F:\jobs\SSD_2B\SSD_2B.flamenco.blend"

Opening the actual blob in blender works, but obviously it's still pointing to files that cannot be found from the blob's directory. I only did this to verify that the blobs were written correctly, and they clearly are.

18:03.360  blend            | Read blend: "F:\file-store\stored\14\0c6efa48408ce1ee0a7296e057e798b1a162d7bc60d542b03d8938f33776c8\1253809.blob"
18:03.391  blend.readfile   | Read library: 'F:\file-store\stored\14\0c6efa48408ce1ee0a7296e057e798b1a162d7bc60d542b03d8938f33776c8\_outside_project\A\1 Amazon_Active_Projects\1 BlenderAssets\Amazon\Scenes\LivingRoom_v2.blend', '//_outside_project/A/1 Amazon_Active_Projects/1 BlenderAssets/Amazon/Scenes/LivingRoom_v2.blend', parent '<direct>'
18:03.391  blend.readfile   | Cannot find lib 'F:\file-store\stored\14\0c6efa48408ce1ee0a7296e057e798b1a162d7bc60d542b03d8938f33776c8\_outside_project\A\1 Amazon_Active_Projects\1 BlenderAssets\Amazon\Scenes\LivingRoom_v2.blend'
18:03.391  blend.readfile   | Read library: 'F:\file-store\stored\14\0c6efa48408ce1ee0a7296e057e798b1a162d7bc60d542b03d8938f33776c8\_outside_project\A\1 Amazon_Active_Projects\1 BlenderAssets\Amazon\Char\Customers\Mom.blend', '//_outside_project/A/1 Amazon_Active_Projects/1 BlenderAssets/Amazon/Char/Customers/Mom.blend', parent '<direct>'
18:03.391  blend.readfile   | Cannot find lib 'F:\file-store\stored\14\0c6efa48408ce1ee0a7296e057e798b1a162d7bc60d542b03d8938f33776c8\_outside_project\A\1 Amazon_Active_Projects\1 BlenderAssets\Amazon\Char\Customers\Mom.blend'
18:03.422  blend.readfile   | LIB: Collection: 'Living Room' missing from 'F:\file-store\stored\14\0c6efa48408ce1ee0a7296e057e798b1a162d7bc60d542b03d8938f33776c8\_outside_project\A\1 Amazon_Active_Projects\1 BlenderAssets\Amazon\Scenes\LivingRoom_v2.blend', parent '<direct>'
18:03.422

Root Cause

Windows creates Windows reparse points. The reparse points are not interpreted properly in all contexts, but only when read from the SMB share. When Flamenco's shared storage is set to a local drive, the reparse points work, but I haven't tested if sharing this folder via SMB works, and you'd probably still have to perform this step.

Workarounds

1. Use local storage: Set shared_storage_path to a local NTFS drive (symlinks work perfectly). This would possibly require hosting the SMB share from that same Windows machine, but I haven't tested if that works. It's possible SMB would behave the same.
2. Run Flamenco Manager on Linux/WSL: Use mfsymlinks mount option for SMB shares. Running the Manager from WSL on the Windows machine works, but running the Manager from the Linux machine hosting the storage makes more sense. This also requires setting up a two-way storage variable.
3. Disable Shaman. Most other Windows users seem to recommend this, and I ran without Shaman for nearly a year and it works. I just wanted to try tackling the root cause, which appears to be SMB. But I can't figure out why me - and other Windows users - can't get it to work, when Sybren's old demonstration appeared to work seamlessly.

Bottom line: has Windows or SMB changed the way Windows reparse points are interpreted over SMB? And what can be done with Shaman (and/or the documentation) do make this work again, if anything?