In NoMachine version 9, when using the KDE Display Manager (KDM), the nxnode and nxexec processes remain active even after a physical user logs out.

After logout, the following processes stay running:

root 12345 ... /usr/NX/bin/nxexec –node ...

user1 12345 ... /usr/NX/bin/nxnode.bin

If these processes are manually killed (e.g., with pkill -9), they are immediately restarted.

This issue appears to be related to KDM not correctly updating the session status in systemd, which causes NoMachine to continue treating the session as active even after logout.

Workaround:

In some systems, the home directory of the 'kdm' user is set to /var, which does not allow the user to create directories. As a result, the nxnode process cannot operate correctly under the 'kdm' user. To handle this, nxnode is started as the special user 'nx':

nx 12345 ... /usr/NX/bin/nxnode.bin

This behavior can be avoided by configuring custom paths for user directories using the following configuration keys in node.cfg file:

CommonLogDirectory "/tmp/nxdir"

UsersDirectoryPath "/tmp/nxdir"

With this configuration in place, nxnode will run as expected:

kdm 12345 ... /usr/NX/bin/nxnode.bin

This issue is reproduced in version 8.17.2 as well.