Arch Linux

While Arch Linux documentation on nbd is scanty and other docs are mostly out-dated, it was hard for a beginner like me to find out why I couldnt connect to a nbd-server neither with oldstyle nor with newstyle. The pre-packaged config leads to errors if only the export-part is being edited, because nbd running as "nbd-user" seems not working correctly.

nbd-client will report:
Negotiation: ..Error: Server closed connection
Exiting.

nbd-server will report:
Spawned a child process
virststyle ipliteral
Child exited with 1

"ps aux | grep nbd" will report that /usr/bin/nbd-server is running as "nbd" not "root"
(to start nbd-server as root I was trying it manually from command-line similar how it is written as an example in man pages > but this isnt recommended, didnt work for me and gave also errors not starting the nbd-server)

Steps to reproduce:
@SERVER:
------
/etc/nbd-server/config
[generic]
user = nbd
group = nbd
# oldstyle = true
[testfile]
exportname = /path/to/testfile
# port = 12345
------
# systemctl start nbd

@CLIENT:
# modprobe nbd
# nbd-client <Server-IP> /dev/nbd0 -name testfile

same if using oldstyle-config without #'s and: nbd-client <Server-IP> 12345 /dev/nbd0

old- and newstyle is working if nbd-server is started without user and group in config > running as root
..maybe this would work with non-root if the user and group permissions for nbd are tweaked?

Additional info:
pkg-version: nbd 3.8-1
configfile: /etc/nbd-server/config (probably taken from https://github.com/yoe/nbd)
tested on: Arch Linux x86_64