NIS users cannot authenticate via NoMachine on Fedora 33, RHEL8 and CentOS 8. A similar problem can occur also on macOS. Problem affects connections by NX protocol and SSH protocol as well.

Error is: Cannot authenticate to the requested node. 

The NoMachine server log reports:

1888 1888 2021-04-01 09:49:12 650.050 NXSERVER WARNING! User USER.DOMAIN doesn’t exist in system.
1888 1888 2021-04-01 09:49:12 650.195 NXSERVER WARNING! NXLogin: Cannot retrieve absolute username for user: USER.DOMAIN

This issue affects also NoMachine v.6.