"Unknown error" and failure to upload folders and multiple files at once in both Web UI and Seafile Client

I have a managed instance of Seafile running on a Ubuntu 22.10 and Nginx reverse proxy, installed with Docker Compose (seafile-mc:latest, mariadb:10.5, memcached:1.6), which works — except for a sync fail with an “Unknown error” message which occurs on uploading either folders or multiple files, with both Web UI and Seafile Client for Linux.

I can provide any log or config file.

in the log file which error ?

Finally I found the solution here: "Unknown erorr" and "Server error" status syncing libraries since Seafile Server CE 7.0.5? - #2 by saljut7

  1. Outside the container, add client_max_body_size 0; to every server { ... } block of the Nginx config file for the reverse proxy. Normally there are two such server blocks: one for port 80 and one for port 443.
  2. Test Nginx config and, if no error is found, restart Nginx: sudo nginx -t && sudo systemctl restart nginx.service