NoMachine Terminal Server Node - Installation and Configuration Guide (v.6)

Welcome to the NoMachine Terminal Server Node - Installation and Configuration Guide v. 6.

What is NoMachine Terminal Server Node for?
NoMachine Terminal Server Node is designed to be specifically installed on a Linux remote node and be part of a multi-node environment ruled by a NoMachine Enterprise Terminal Server. It is not a standalone server and cannot accept direct connections to its host.

Once installed, the NoMachine Terminal Server Node has to be added to the Enterprise Terminal Server. Users will connect to the Enterprise Terminal Server which is the single point of access to all the available nodes. Depending on the Enterprise Terminal Server's configuration, users will be able to choose the node on which to run their virtual desktop and/or sessions will be automatically load-balanced among the nodes (default).

Setting-up a multinode environment made of a NoMachine Enterprise Terminal Server plus a scalable number of Terminal Server Nodes is a solution for centralizing access to multiple hosts and distributing the load among them.

A Graphical Interface
The NoMachine Terminal Server Node package includes the NoMachine GUI which provides the graphical interface (Server preferences) for administering the Terminal Server Node services. This GUI also acts as client for running sessions and connecting to remote desktops.

The most common operations detailed in this guide can be performed by the NoMachine UI and the Server preferences panel running on the local installation of the Terminal Server Node:

More details about the Server preferences GUI can be found in the dedicated guide available in the Documents section at: https://www.nomachine.com/all-documents

The Terminal Server Node is ready once installed
Installation provides a fully operative NoMachine node with a default configuration suitable for the majority of environments. All the necessary services are automatically started. Just add it to the Enterprise Terminal Server.

A node of the Enterprise Terminal Server
NoMachine Terminal Server Node, available for Linux only, supports unlimited concurrent virtual desktops. A virtual desktop is an individual instance of the remote desktop. Sharing of a virtual desktop is also supported. The number of users is not limited.

Document Conventions and Important Notices
The following conventions are used in this guide:

BaseDirectory
is the base directory where the NoMachine binaries and libraries are installed.
By default, BaseDirectory is: /usr.

InstallationDirectory
is: BaseDirectory/NX, i.e. /usr/NX.

The command line interface
NoMachine server and node programs have a command line interface to execute operations.

You need to be a privileged system user to access all these functionalities. These commands can be run from an xterm or similar using the sudo utility or as root.

On Linux invoke the 'nxserver' and 'nxnode' programs from /etc/NX, for example:

Online Resources
Visit the NoMachine Support Area to access a variety of online resources including the NoMachine Forums, tutorials and FAQs: https://www.nomachine.com/support

Find a list of all documents and tutorials: https://www.nomachine.com/all-documents

Use the Knowledge Base search engine to access articles, FAQs and self-help information: https://www.nomachine.com/knowledge-base

Leave Feedback About This Guide
Our goal is to provide comprehensive and clear documentation for all NoMachine products. If you would like to send us your comments and suggestions, you can use the contact tool available at https://www.nomachine.com/contact-request, selecting Web Quality Feedback as your option.

Supported Operating Systems
Windows 32-bit/64-bit XP/Vista/7/8/8.1/10

Windows Server 2008/2012/2016

Mac OS X Intel 64-bit 10.7 to 10.14

Linux 32-bit and 64-bit

RHEL 4 to RHEL 8
SLED 10 to SLED 15
SLES 10 to SLES 15
openSUSE 10.x to openSUSE 15.x
Mandriva 2009 to Mandriva 2011
Fedora 10 to Fedora 30
Debian 4.0 to Debian 9
Ubuntu 8.04 to Ubuntu 19.04

Raspberry Pi 2/3 ARMv6/ARMv7/ARMv8

Hardware requirements
Intel Core2 Duo or AMD Athlon Dual-Core or equivalent
1 GB RAM
Network connection (either a LAN, or Internet link: broadband, cable, DSL, etc...)
Size required on disk:
Linux 115 MB

Software requirements
A desktop environment must already be installed. This applies also to headless Linux machines.

Web sessions and NoMachine client's sessions are supported. Users must connect to the Enterprise Terminal Server in order to run the session on the Terminal Server Node host (the node doesn't accept direct connections).

Even if it's advisable to upgrade client installations to the same version 6 of the Enterprise Terminal Server and Terminal Server Node, compatibility with clients v. 4 and 5 is preserved.

It's strongly advisable to keep version of Enterprise Terminal Server and of its Terminal Server Nodes always aligned.

NoMachine v. 6 is not compatible with the legacy NX version 3.5.0 (no longer supported since December 2016).

Installing for the first time
You can install, update and uninstall using the graphical package manager of your Linux distribution or from command line by running commands from an xterm or similar with the sudo utility, or as root user if you don't have sudo installed. Instructions below refer to installation by command line.

If you own a customer license we recommend you download the package from your Customer Area: https://www.nomachine.com/support#login.

Successive updates
The update procedure for server and node installations requires all NoMachine services to be stopped in order to correctly replace libraries and binaries. This implies that the Terminal Server Node is not accessible to users during the update procedure. Current sessions will be terminated, users will be able to connect again later.

There are two ways to update your current installation:

If you want to install to default location, namely /usr/NX/:

INSTALL

UPDATE

UNINSTALL

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For non-default locations, for example /opt/NX:

INSTALL # rpm -ivh <pkgName>_<pkgVersion>_<arch>.rpm --prefix /opt UPDATE # rpm -Uvh <pkgName>_<pkgVersion>_<arch>.rpm --prefix /opt UNINSTALL # rpm -e nomachine-terminal-server-node

If you want to install to default location, namely /usr/NX/:

INSTALL

UPDATE

UNINSTALL

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For non-default locations, for example /opt/NX:

INSTALL $ sudo NX_INSTALL_PREFIX=/opt dpkg -i <pkgName>_<pkgVersion>_<arch>.deb UPDATE $ sudo NX_INSTALL_PREFIX=/opt dpkg -i <pkgName>_<pkgVersion>_<arch>.deb UNINSTALL $ sudo dpkg -r nomachine-terminal-server-node

If you want to install to default location, namely /usr/NX/, ensure that the package is placed there.

INSTALL

UPDATE

UNINSTALL

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For non-default locations, for example /opt/NX:

INSTALL $ sudo NX_INSTALL_PREFIX=/opt /usr/NX/nxserver --install UPDATE $ sudo NX_INSTALL_PREFIX=/opt /usr/NX/nxserver --update UNINSTALL $ sudo /opt/NX/scripts/setup/nxserver --uninstall $ sudo rm -rf /opt/NX

Customer packages
include a temporary (30-days) node.lic file for evaluation.
Such license file has to be replaced with the customer's license file acquired from NoMachine. This can be done via the NoMachine server GUI in the 'Updates' panel: click on the node.lic links to open its license panel and replace the license.

You can find a Guide for GUI usage in the Documents section on the NoMachine web site: https://www.nomachine.com/all-documents. Look for the keyword 'license' to find out in the knowledge base, section 'Articles' how to activate licenses manually: https://www.nomachine.com/knowledge-base.

To verify from command line that node.lic is correctly in place and check its validity, you may run:

First of all, ensure that the user has a system account on the Terminal Server Node host: you can create it by using system tools or by using nxserver commands. Empty password is not supported. Note that users need to have a valid system account on the Enterprise Terminal Server host and on each of the Terminal Server Nodes. Username must be the same on all machines but the password can be different.

Once added to the Enterprise Terminal Server, the Terminal Server Node is ready to go.

To connect via web, the end-user should point the browser on his/her device to the name or IP address of the Enterprise Terminal Server host.

In a similar way, when connecting form a client device, the user will have to specify the IP or hostname of the Enterprise Terminal Server while creating the connection.

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I	Auto-reconnection is supported: when the connection is lost for whatever reason (including when the client host has entered sleep mode), the client will automatically try to reconnect for as long as the user keeps the GUI or the web page open. If reconnecting is not possible, then the user will have to reconnect manually.
II	IPv6 is supported: specify the IP address of the server host in IPv6 format (e.g. 2001:0:5ef5:79fb:30c6:1516:3ca1:5695) if you want to use it instead of IPv4.

By default, the NoMachine Enterprise Terminal Server makes available the Terminal Server Node for the automatic load-balancing of virtual desktops. This means that the server, based on its load-balancing algorithm, will select the node where the new virtual desktop will be started. The server can be also configured to let the user choose the node. See the NoMachine Enterprise Terminal Server guide for instructions to configure multi-node access: https://www.nomachine.com/all-documents

In the case of web sessions, by default, session data is streamed in video frames compressed and decompressed by using the MJPEG lossy algorithm, which is the video-format widely supported by browsers.

Oher video codecs like VP8 and H.264, require a browser which supports WebRTC and HTML5.

NoMachine web sessions use the H.264 video streaming when the following requirements are all met, otherwise VP8 is used. In practice, when WebRTC is enabled, the H.264 or VP8 encoding will be used, otherwise MJPEG will be the codec:

(*) Terminal Server Node packages for customers provide the H.264 libraries necessary to support the SW H.264 encoding.

HW H.264 encoding is possible when the Terminal Server Node host machine has a hardware accelerated video card (GPU) with any of the supported microarchitectures: Nvidia Kepler microarchitecture onward and Intel Quick Sync processors. Enabling HW acceleration by Quick Sync requires however a manual configuration as explained here: https://www.nomachine.com/AR09O00938

Optimizations
Optimizations can be done in two ways: (I) by adjusting display settings in the session or (II) by enabling WebRTC.

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You may verify which encoding method is in use from the NoMachine menu inside the session: press ctrl+alt+0 or click on the page peel in the upper right corner of the window to open it. Then click on the 'Display' button and finally on 'Display settings'. The codec actually in use is reported at the bottom left of the menu.

Sessions run by NoMachine client use a combination of video and image encoding based on standard codecs and a number of techniques developed by NoMachine. Frames are encoded into a video stream optimized by means of a compression and decompression algorithm of real-time image and audio data. VP8, H.264 and MJPEG encoding are supported.

In general VP8 and H.264 are suitable for all situations, while MJPEG can be an alternative when the end-user's computer is less powerful and the user is experiencing slow responsiveness.

The display encoder can be changed on the server:

from the GUI
In the GUI in the Server Performance panel.

or in the node configuration file
Enable the use of a specific codec by editing the node configuration file and enabling the following two keys:

EnableDisplayServerVideoCodec 1
DisplayServerVideoCodec CODEC

where CODEC can be: 'vp8','h264' or 'mjpeg'. For example:
EnableDisplayServerVideoCodec 1
DisplayServerVideoCodec mjpeg

The X11 vector graphics mode (previously called 'lightweight mode') is enabled by default for (i) virtual desktops and (ii) custom sessions in floating window mode. This mode is mainly a set of NoMachine techniques to compress and optimize the X11 protocol (by applying the same alghoritms available with the NX compression protocol v. 3). These compression techniques are applied to all non-video contents like textual elements, while multimedia content is encoded in a video stream (VP8 or H.264).

The X11 vector graphics mode is useful for avoiding loss of image quality and in general is the best option when working with traditional GUIs or a large amount of text. However it's not advisable for multimedia content or applications with many graphical effects.

This mode can also help to reduce bandwidth usage, decrease the HW requirements on client and server (expensive video encoding/decoding operations are applied only to multimedia contents), increase responsiveness on slow link and end-users' clients without hardware accelerated video encoding/decoding capabilities.

You can disable/enable the X11 vector graphics mode
via the GUI
in the Server preferences GUI -> Performances panel

or in the node configuration file
for disabling the X11 vector graphics mode, edit the node configuration file, uncomment and set:
AgentX11VectorGraphics 0

or to enable it:
AgentX11VectorGraphics 1

TIPS
I	In the case of slow bandwidth, decreasing the quality level of images could help but if you need to have a perfect image without quality loss, you have to increase the display quality instead. It's also suggested to disable multi-pass encoding to avoid the 'out of focus' effect: multi-pass is an encoding technique which uses multiple passes to reach progressively the best definition of the image.
II	Quality level and multi-pass encoding can be tuned from the NoMachine menu inside the session in the Display -> Change settings panel. (Ctrl+alt+0 or click on the right upper corner of the window to open the NoMachine menu).

In NoMachine virtual desktops and custom sessions, OpenGL rendering is done by default by software components. This means that rendering tasks are accomplished by CPU and not offloaded onto GPU. Such operations could be resource-demanding, especially in the case of 3D desktop graphics effects, and make the user interface look slow.

A possible alternative is to configure the NoMachine server to use the VirtualGL libraries (included in the NoMachine package) and therefore activate support for HW accelerated OpenGL applications. This allows OpenGL applications, namely 3D applications, to use server side graphics hardware.

In order to activate support for VirtualGL, follow instructions at http://www.nomachine.com/AR05P00982

The configuration files for the Terminal Server Node are mainly node.cfg. In some cases it may be necessary to adjust some settings also in the server configuration file, server.cfg. In effect, the Terminal Server Node package includes the nxserver program as well, which still manages users and sessions on localhost but doesn't accept connections unless they come from the Enterprise Terminal Server.

Configuration files are placed in the BaseDirectory/NX/etc directory:
/usr/NX/etc/server.cfg
/usr/NX/etc/node.cfg

The Default Configuration
NoMachine Terminal Server Node comes with a default configuration that is sufficient to grant a working setup in the majority of environments. NoMachine administrators can tune their installation at any moment and according to their specific needs by setting the related configuration keys. In some cases this will require to restart all NoMachine services.

Edit the Configuration Files
NoMachine configuration files are text files made up of a number of key-value pairs. All the configuration files can be edited manually by a text editor, e.g. 'vi'.

Be sure to uncomment the configuration key (i.e., remove the '#' pre-pended to the key) to set a value different from the default.

When a configuration key supports an on/off status, set value to '0' to disable it and to '1' to enable it.

Make Changes to the Default Configuration Effective
Changes will be effective with the next new connection without the need to restart services if not otherwise specified.

For each session, NoMachine uses ports that are used only locally on the node host and network ports.

Some ports are mandatory and must be free, e.g. the session display number and the connection port. Other ports are used for services that can be disabled, e.g. USB forwarding.

It is possible to hide or show the !M (the Monitor) icon in the system tray. When the icon is hidden, notification messages will still be displayed when users are connecting. This can be configured
from the GUI:
In the Server status -> Server preferences -> Security panel by selecting 'Hide the NoMachine icon in the system tray'. When the icon is hidden, notification messages will still be displayed when users are connecting.

or in the node configuration file
This setting is ruled by the DisplayMonitorIcon key in the node configuration file. If you change them manually by editing the file, you then need to restart the server to make changes effective.

To hide the !M in the system tray set:
DisplayMonitorIcon 0

To display the !M in the system tray set:
DisplayMonitorIcon 1

In both cases, then restart the server:

By default NoMachine issues a balloon message to notify about events like user's disconnection or user's requests for connecting. You can disable notification messages by setting the following key in the node configuration:
DisplayMonitorNotifications 0

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If the displaying of monitor's notification messages is disabled, the desktop owner will be unable to accept connection's requests by other users. Configure trusted users on the Enterprise Terminal Server if you need to allow connections without explicit authorization.

If you want to disable the launching of the Whiteboard from the Monitor menu, edit the node configuration file to have:
EnableWhiteboard 0

Then restart the server:

You can manage create and delete user accounts by using tools provided by your Operating System or the NoMachine server commands as explained below. Note that the user who will connect by NoMachine must have an account also on the Enterprise Terminal Server (username must be the same, password can be different).

Creating Accounts