nbd-server(1) on Linux
The text 529797344d50, as Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch) shipped it.
serve a file as a block device to other computers running the GNU/Linux(tm) or GNU/Hurd Operating System
Flags it lists
-
-C -
-M -
-V -
-c -
-d -
-m -
-r