SMB Path Length Issue(?)

restic 0.18.1 compiled with go1.25.1 on darwin/arm64
restic backup --ignore-inode /Volumes/AjamiLab

I am trying to back up a huge samba mount - about 46,455,557,455,872 bytes (46.46 TB on disk). I can’t run it from the machine hosting the mount, I have to do it over samba or SFTP (ugh, don’t ask). I have a full snapshot of 37.60 TB now (dedupes and max compresses down to ~18TB). Apparently there’s some paths that I don’t have access to. I’m rerunning the snapshot (should take ~72 hours) and logging stderr this time so I can figure out what is missing.

The first error has hit, and it says…

error: readdirnames /Volumes/AjamiLab/BGMP_student_space/data_transfer/SCL230321BA/Aligned/Aligned/SCL230321BA_PPMI17_A_517/SC_MULTI_CS/SC_MULTI_CORE/MULTI_GEM_WELL_PROCESSOR/VDJ_T_GEM_WELL_PROCESSOR/SC_VDJ_CONTIG_ASSEMBLER/ASSEMBLE_VDJ/fork0 failed: fdopendir /Volumes/AjamiLab/BGMP_student_space/data_transfer/SCL230321BA/Aligned/Aligned/SCL230321BA_PPMI17_A_517/SC_MULTI_CS/SC_MULTI_CORE/MULTI_GEM_WELL_PROCESSOR/VDJ_T_GEM_WELL_PROCESSOR/SC_VDJ_CONTIG_ASSEMBLER/ASSEMBLE_VDJ/fork0: not a directory

I assumed it was some irregular file but, when I navigate to the path… it enumerates just fine:

So I’m wondering if there’s some path character limit with MacOS / samba, or if it’s on Restic’s side, or what? Not sure where to go from here. Going to wait for this snapshot to finish and get a list of what fails and copy out manually I suppose. But I thought I’d post here and see if anyone had any ideas.

These scientists are awful with file naming - horrendously long filenames, every special character you can think of (and some you can’t), leading/trailing spaces in file/folder names, and as many subdirectories as you can imagine. I’m constantly dealing with this sort of thing. Usually Restic is one of the only tools I have that just takes whatever I give it, but not today apparently haha

Interesting! There seems to be such a limit that can be overridden but then might fail at some other point. This is what I found:

Just don’t tell the scientists to shorten them or you’ll end up with abbreviations that can’t even be reversed using quantum computing.

Did you ever find out what the problem was?

I did not. We eventually ended up using Globus to transfer all the data instead.