VNC sessions are supported by NoMachine NoMachine Terminal Server and Enterprise Terminal Server but are not enabled by default.

In its current implementation, the VNC server doesn't have an empty password set.

To enable VNC virtual desktop sessions, perform steps 1-4 below on the NoMachine host.
 

Let's call:

host A, the NoMachine Linux host.

host B, the VNC Server host to be connected via RFB.

For multinode environments
In case of multi-node environments (Enterprise Terminal Server + NoMachine Terminal Server Nodes), you need to perform the following operations on each of the NoMachine node machines you want to use for starting VNC sessions.

Step 1:  Be sure you have a VNC client

Ensure that VNC viewer is installed on host A. You can use for example TightVNC, RealVNC or TigerVNC.

Check if the VNC password utility is available (try to execute the vncpasswd command) on host A.

If not, you need to install also the VNC server on host A. The VNC server is necessary only to provide the vncpasswd utility when it's not installed by the VNC client.

Step 2: Instruct NoMachine to launch the VNC client

On host A edit the node configuration file: /usr/NX/etc/node.cfg.

Specify path and name of the command to launch the VNC client: ensure that the CommandStartRFB key is not commented and set a proper value.

For example for TigerVNC, RealVNC and TightVNC:

CommandStartRFB "vncviewer -fullscreen"

Step 3: Add VNC to the list of available session types in the node configuration file

On host A edit /usr/NX/etc/node.cfg.

Uncomment and edit the AvailableSessionTypes key.  Add value: vnc if it is not present yet.

For example:

AvailableSessionTypes physical-desktop,shadow,unix-xsession-default,unix-gnome, vnc

Step 4: Add VNC to the list of available session types in the server configuration file

On host A edit the server configuration file: /usr/NX/etc/server.cfg.

Uncomment and edit the AvailableSessionTypes key. Add value: vnc if it is not present yet.

For example:

AvailableSessionTypes physical-desktop,shadow,unix-xsession-default,unix-gnome, vnc
 

Step 5: Launch the NoMachine VNC virtual desktop

How to connect by the client

On the user's machine, launch NoMachine (client) and create a new connection.

In the 'Host' field specify hostname or IP address of host A.

Launch the connection, in the login form provide username and password of a user account enabled to log-in to host A.

Once connected to the NoMachine server on host A, click on 'Create a new desktop or custom session'.

Then choose 'Create a new VNC virtual desktop'.

In the 'VNC remote desktop' panel, provide IP or hostname of the VNC server (host B) and port and continue.

In the next panel you will be requested to provide username and password to login to the VNC server.

Tip:

by clicking on 'Save this setting in the connection file' and 'Save this password in the connection file', all data will be re-used next time.

How to connect by the web

Open a browser and point it to:

http://serverName:4080

where serverName is hostname or IP of host A.

In the login form provide username and password of a user account enabled to log-in to host A.

Once connected to the NoMachine server on host A, click on 'Create a new desktop or custom session'.

Then choose 'Create a new VNC virtual desktop'.

In the 'VNC remote desktop' panel, provide IP or hostname of the VNC server (host B) and port and continue.
In the next panel you will be requested to provide username and password to login to the VNC server.

It's not possible to save settings in case of web sessions.