[SOLVED] Single file failing with "generic error" and recreating tmp file

[tomasz86]

I have had this problem for ~2 days with one folder getting stuck in this state, where it cannot finish synchronisation with a single file stuck in a “generic error”.

The file is indeed not syncing, but it seems that a new ~syncthing~xxx.tmp temp file keeps getting created in the folder in question. I have tried setting the folder to Receive Only and using STRECHECKDBEVERY=1s, but to no avail. The file itself is nothing special, and other files in the same folder do continue to be synced properly. It is only this one file that fails.

This is a VM, so I do not suspect any hardware failures. What can be a possible reason for this? I cannot post the full debug logs publicly, as this is a real system with possibly sensitive file names.

Syncthing version is 1.11.1.

[imsodin (Simon)]

That’s a protocol error that occurred when trying to pull a block from a remote. We should add some context on that error, e.g. which device is the origin of the error. If you know which device it is pulling from, you can enable model debug logging there and look for lines containing REQ(in), which will have details on why it fails.

[tomasz86]

Thank you. I have found the culprit.

[D4DZU] 2020/11/09 model.go:1442: DEBUG: model@0x12a44000 REQ(in): XXXXX: "ghgck-scplg" / "xxx" o=0 s=1536 t=false
[D4DZU] 2020/11/09 model.go:2426: DEBUG: readOffsetIntoBuf.Open xxx open \\?\xxx: Access is denied.
[D4DZU] 2020/11/09 model.go:1509: DEBUG: model@0x12a44000 REQ(in) failed reading file (open \\?\xxx: Access is denied.): XXXXX: "ghgck-scplg" / "xxx" o=0 s=1536

I am not sure what happened, but the file’s permissions were messed up. I fixed them, and then the synchronisation finally succeeded.