I use Samba 4.11.6 with ubuntu 20.04 & Mac os Big Sur 11.0.1. I connected my macbook and server (intel nuc) via thunderbolt 3. It works fast, speeds around 800MB/s. I can easily transfer multiple files or 1 large file, but when I try to transfer any web project with a lot of files and subfolders, the finder freezes and only hard reset helps. I tried transferring files via finder and via cp -av ..., the result is the same - the terminal freezes and control + c does not work. Several files with a total size of a couple of KB are transferred and nothing else. The problem is similar to this jamf.com/jamf-nation/discussions/26464/macos-high-sierra-10-13-2-finder-issues-when-copying-files-in-mounted-shares. I tried changing nsmb.conf to this [default] signing_required=no dir_cache_off=yes But it didn't help at all :( When I don't connect via thunderbolt 3, but when i connected via wifi, I can transfer my project to the smb folder.