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

What is NoMachine Enterprise Terminal Server for?
NoMachine Enterprise Terminal Server is a standalone server that provides access to unlimited concurrent virtual desktops distributed on multiple machines (nodes). Designed for setting-up a multinode environment, it works in conjunction with NoMachine Terminal Server Node(s). The multi-node system provides individual instances of the remote desktop (terminal services) and lets users having their own separate desktop environment. Each user has his/her own desktop or application, store and manage files inside the session and, in case, share his/her own resources with another user. The session load can be also balanced among the nodes according to different methods.

Available for Linux, the Enterprise Terminal Server accepts connections via a browser (thanks to its built-in web server) or via NoMachine client.

Additionally, it can also be federated under a Cloud Server. This solution is suitable to centralize the access to multiple NoMachine servers distributed across the world.

A Graphical Interface
The NoMachine Enterprise Terminal Server server package includes the NoMachine User Interface which provides the graphical interface (Server preferences) for administering the server and its services. It provides also the client User Interface for running sessions and connecting to remote desktops.

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 server:

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

The server is fully operative once installed
Installation is conceived to provide a fully operative NoMachine server with a default configuration suitable for the greatest part of environments. All the necessary services are automatically started.

A standalone server
NoMachine Enterprise Terminal Server, available for Linux only, supports unlimited concurrent virtual desktops distributed among its Terminal Server Nodes and -by default- its host machine. A virtual desktop is an individual instance of the remote desktop. It supports also connections to the physical display of its host. Number of users is not limited. NoMachine Enterprise Terminal Server is a single server (standalone server), to all effects.

A federated server
NoMachine Enterprise Terminal Server can be also federated under a Cloud Server v. 6 which provides a single point of access to multiple server subsystems. In this case, it's possible configuring the Enterprise Terminal Server to not accept direct connections. For more specific instructions about federating the Enterprise Terminal Server, refer to the Cloud Server administrative's guide.

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 included 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://kb.nomachine.com

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 195 MB

Software requirements
A desktop environment must already be installed. This applies also to headless Linux machines. Connections by the web and by NoMachine clients are supported.

Compatibility with older versions
Connections by the web and by NoMachine clients are supported.
Even if it's advisable to upgrade client installations to the same version 6 of the Enterprise Terminal Server, compatibility with clients v. 4 and 5 is preserved.

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

Version of Enterprise Terminal Server and Terminal Server Node must be the same on the main server host and on each of the remote nodes.

Note also that when the Enterprise Terminal Server works as a federated server, NoMachine Cloud Server v. 6 requires a client v. 6.

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 to download the package from your Customer Area: https://www.nomachine.com/support#login.

Successive updates
The update procedure for server and node installations requires to stop all NoMachine services in order to correctly replace libraries and binaries. This implies that the Enterprise Terminal Server 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

TIP

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-enterprise-terminal-server

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

INSTALL

UPDATE

UNINSTALL

TIP

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-enterprise-terminal-server

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

INSTALL

UPDATE

UNINSTALL

TIP

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

Customers' packages
include a temporary (30-days) node.lic and server.lic files for evaluation.
Such license files have to be replaced with the customer's license files acquired from NoMachine. This can be done via the NoMachine server User Interface in the 'Updates' panel: click on the server.lic and node.lic links to open their license panel and replace the license.

You can find a Guide for UI 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://kb.nomachine.com.

To activate the license files from command line instead, please follow instructions here: https://www.nomachine.com/AR11O00942

To verify from command line that server.lic and node.lic are correctly in place and check their validity, run:

A NoMachine multi-node environment is made up of a central server (the Enterprise Terminal Server) and nodes (Terminal Server Nodes) to which the server sends connection requests. Note that only the Enterprise Terminal Server is able to accept direct connections to its host, it acts as a single point of access to the nodes. A Terminal Server Node is not a server, it refuses all direct connections and can work only behind an Enterprise Terminal Server. By default, virtual desktops can be started also on the Enterprise Terminal Server host.

To set-up the multinode environment:
Step 1- Install NoMachine Enterprise Terminal Server on machine A. Activate the customer's license files, server.lic and node.lic.

Step 2- Install NoMachine Terminal Server Node on machine B. Activate the customer's license file, node.lic (TSN has only one license file!).

Step 3-Add the node to the server.

For high-availability, it's possible to set-up two Enterprise Terminal Servers in a failover cluster, as shown in the following diagram.

The multi-node setup will automatically make available the Terminal Server Nodes for the automatic load balancing of virtual desktop sessions among such nodes and the Enterprise Terminal Server host. The last can be excluded from the list for load-balancing. If needed, you can activate the 'manual-node' selection of the nodes. It means that all users, or only some specific users, will be able to choose on which node to create their virtual desktop.

TIP

It's recommended to keep versions of Enterprise Terminal Server and Terminal Server Nodes always aligned. You may find step-by-step instructions to update a multi-node environment in the 'All NoMachine documents' section here: https://www.nomachine.com/all-documents.

You can add the Terminal Server Node from the NoMachine User Interface.
Ensure to have an account with NoMachine administrator's privileges. To assign these privileges use:

Then connect via NoMachine client to the Enterprise Terminal Server as a NoMachine administrator. Click on the 'New node' button to add the Terminal Server Node.
Step-by-step instructions are available in the 'Adding Terminal Server Nodes to Enterprise Terminal Server via the UI' tutorial on our web site: https://www.nomachine.com/all-documents.

Otherwise you can add the node from command line.
Execute the following command on the Enterprise Terminal Server Host:

When running the --nodeadd command, NoMachine Enterprise Terminal Server tries to connect to the node. If it cannot authenticate using NoMachine server's public key, it will ask you to login as a privileged user to that node and will try to add the server public key there. It's therefore necessary to have an account with administrative privileges on each Terminal Server Node.

You can specify settings different from the default ones while adding the node or later by editing it. The available options are:

For example:

TIP

If two Enterprise Terminal Servers are set in a failover cluster, when a new node is added to the primary server or removed, it's then necessary to update the cluster to synchronize it. For example, execute on the primary Enterprise Terminal Server:

/etc/NX/nxserver --nodeadd testdrive2.nomachine.com /etc/NX/nxserver --clusterupdate

The following command permits to synchronize node information on server side:

The other commands available to manage the remote nodes are:

TIPS
I	To modify name of the node, remove it and add it again by specifying the new IP or hostname.
II	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 password can be different.

It's possible to configure NoMachine Enterprise Terminal Server to manage the following alternative configurations:

To verify current settings, run:

The following alternative configurations apply to the whole system, i.e. they apply to all users.

Configuration I
This is the default configuration. The server will use only automatic load-balancing and rely on any of the available load-balancing algorithm to choose the node where the virtual desktop will be started. The manual node selection is disabled.

Profile rules to set-up this configuration are:

Configuration II
The server will allow users to choose the remote node (manual node selection) where to start their virtual desktops. The automatic load-balancing of sessions is disabled.

Profile rules to set-up this configuration are:

Configuration III
The server will load-balance virtual desktops according to any of the available algorithms and will allow the manual selection of the nodes as well. It's possible to configure a node only for load-balancing or manual selection.

Profile rules to set-up this configuration are:

Configuring load-balancing and manual node selection on a per-user basis
The previous configurations I, II and III can be also set on a per-user or per-group of users basis by specifying the --user USERNAME and --group GROUPNAME options respectively.

The following examples assume to have a default environment (multi-node support and load-balancing enabled and manual node selection disabled for the whole system).

Limiting the number of virtual desktops on each Terminal Server Node
The following profile rule permits to set the maximum number of concurrent virtual desktops that can be run on each of the available nodes:

NoMachine Enterprise Terminal Server supports multiple alternatives to manage the load-balancing of virtual desktops:

CONFIGURATION I - Plain round robin algorithm
To make the server using a plain round-robin algorithm, set in the server configuration file:
LoadBalancingAlgorithm round-robin

CONFIGURATION II - Weighted round robin algorithm (default)
As for configuration I, the following key has to be set in the server configuration file:
LoadBalancingAlgorithm round-robin

In order to apply the weighted round algorithm it's necessary to assign a weight to at least one of the remote nodes (all nodes which don't have weight set have weight 0 by default). If weight is not assigned, this algorithm is equivalent to a plain round-robin.

The node with the higher weight is the node where the session will be started first. If the limit for connections on the node is reached, the algorithm falls back to choose the first node provided by the server list.

A weight can be assigned while adding the node by using the '--weight WEIGHT' option or can be specified later by editing the node:

CONFIGURATION III - Custom algorithm
You can create a custom script according to your needs. The custom load-balancing script has to be written in Perl and Perl has to be installed on the system.

To use a custom algorithm for load-balancing of virtual desktops set in the server configuration file:
LoadBalancingAlgorithm custom

Then provide path and name to the custom script in the following server configuration key:
NodeSelectionScript "/usr/NX/scripts/lb/nxweightedroundrobin.pl"

The installation package comes with a custom script: /usr/NX/scripts/lb/nxweightedroundrobin.pl written in perl and intended to provide an example.

The algorithm of this script, given a weight for each node and a limit of connections for that node, selects the node with a higher weight counted as:
weight = [weight of node] - [number of sessions connected to the node]

Since v. 6.1, the following environment variables are available in the script: NX_USERNAME and NX_CLIENT_IP.
In this way the custom load-balancing algorithm may take into account which user is connecting and for example force the server to start the session on a particular node.

Since v. 6.3.6, the server passes to the custom script only those nodes that are effectively available to the user.

CONFIGURATION IV - Load average
The server can be configured to choose the node with the minimum load average. To apply this configuration, edit the server.cfg file and set:
LoadBalancingAlgorithm load-average

CONFIGURATION V - System load (from v. 6.5 onward)
The server can be configured to choose the node with the lowest system load calculated according to the algorithm specified in the /usr/NX/scripts/lb/nxreportsystemload.pl script set on the node.

By default, the algorithm takes in account the CPU Run Queue normalized by CPUs/Cores and I/O Wait and applies the following calculation:

load = (procs_running / cpus) + procs_blocked

This calculation can be edited in the nxreportsystemload.pl script and adapted to different situations.

To apply this configuration, edit the server.cfg file and set:
LoadBalancingAlgorithm system-load
and restart the NoMachine server:

A Practical Example
Premises
Load-balancing is configured to use the Load-average algorithm. Two or more nodes have zero-load set. Some of these zero-load nodes are hosting NoMachine sessions in status disconnected. Other zero-load nodes don't have NoMachine sessions.

Requirement
According to the load-average algorithm, the server chooses the node with the minimum load. This doesn't take into account if sessions are already running or not on the node. It's instead necessary that the server chooses the zero-load node without NoMachine sessions as first option.

Solution
Adopting a custom script which sets a weight for each NoMachine session and uses a combination of load average and number of sessions to choose the node where to start a new session.

To use this script, named in our example 'customLoadAverage.pl':
1. Copy the script below to a directory accessible by the nx user, for example: /usr/NX/scripts/lb/.
2. Set read-execute permissions for the nx user.
3. Edit server.cfg and set:
LoadBalancingAlgorithm custom
NodeSelectionScript "/usr/NX/scripts/lb/customLoadAverage.pl"

The customLoadAverage.pl script is:

Notes:

A NoMachine failover cluster is a group of two servers that work together to maintain high availability of applications and services running on the Terminal Server Node hosts in a multi-node environment. This is an active/passive cluster where the primary server is at the beginning active and ready to accept users' connections, while the secondary server is passive, its task is to constantly monitor the primary server.

When the secondary server looses contact with the primary server, the cluster failover occurs: the secondary server takes place of the primary server to grant the continuity of services. Sessions running on the remote nodes continue to stay running, management of server-node connections is passed from the primary to the secondary server, the virtual IP of the cluster is taken by the secondary server, an ARP notification is sent to local network devices to update their ARP cache entries (Ethernet MAC to IP address link associations).

Pre-requisites for creating the cluster are:

Set-up the failover cluster

STEP 1: Identify which Enterprise Server will be the primary server (ETS1) and which will be the secondary server (ETS2).

STEP 2: Ensure that ETS1 is already configured for the multi-node set-up (as explained in the previous paragraph).

STEP 3: Prevent sessions from being started on ETS1 and ETS2.
On ETS1, identify the node local to the server by running:

It's not necessary to repeat this operation on ETS2: DBs of the secondary server ETS2 will be automatically syncrhonized with DBs of the primary server ETS1 when ETS2 is added to the cluster.

STEP 4: Set-up the primary server role to ETS1.
On ETS1 execute:

Optionally you may specify the following parameters while creating the cluster with the previous command:

STEP 5: Set-up the secondary server role to ETS2
Always on ETS1 execute:

Optionally it's possible to issue the --interface INTERFACE and --netmask MASK parameters to specify a network interface and subnet mask different from default 'eth0:0' and '255.255.255.0'.

STEP 6: Restart ETS1 and ETS2.
Firstly on ETS1, then on ETS2 execute:

TIP

It's mandatory to restart both the primary and the secondary server.

A practical example
Target is to set-up the failover cluster between 2 NoMachine Enterprise Terminal Servers hosts, Enterprise1 and Enterprise2.

1. Install your Enterprise Terminal Server on Enterprise1.

2. Install the Terminal Server Node on node1 and on node2.

3. Add node1 and node2 to Enterprise1:

4. Install the second Enterprise Terminal Server on Enterprise2.

5. Assign to Enterprise1 the active role (execute the command on Enterprise1):

6. Associate the second Enterprise Terminal Server to the cluster with the following command (execute the command on Enterprise1):

7. Restart nxserver on Enterprise1:

8. Restart nxserver on Enterprise2:

9. Connect via NoMachine client or browser to virtual IP (in our example it's: 172.17.10.100).

Finally, you can then verify that high-availability works as expected.

10. Kill Enterprise1: you will be disconnected.

11. Reconnect to virtual IP (172.17.10.100 in our example) while leaving Enterprise1 down and you should be given the option to connect again as Enterprise2 should have now taken over duty.

TIP

When the mutual connections between cluster servers are re-established and both the primary and the secondary server are available, the primary server should take back its role of active server, while the secondary server will be restarted and will be in the passive state. No manual intervention is needed for restoring the original primary server.

Tuning the Failover Cluster Parameters
Default settings apply to the most common cases. It may be necessary, however, to tune some parameters to fit some specific business requirements or network conditions.

The global failover time depends on:
global failover time = grace period + timeout + router's convergence time

These are the default settings which define the cluster's heartbeat and rule health detection between the two NoMachine servers in the cluster:

Administering the Failover Cluster
The primary and secondary Enterprise Terminal Servers use a RSA key pair to connect and synchronize information between their databases. This key pair is valid only for the nx user. You may replace the default RSA key-pair provided with the installation by generating your own key-pair. Detailed instructions are provided in the guide for using different keys and certificates with NoMachine, available here: https://www.nomachine.com/all-documents.

Once replaced, remember to update the cluster configuration by running on the primary server or on the secondary server (configurations will be propagated to the other server in the cluster) the following command:

Adding or removing a new node to the primary server
When a new node is added to the Enterprise Terminal Server (primary server) or removed, it's then necessary to update the cluster to synchronize it. For example, execute on ETS1:

Changing cluster's settings
To change network interface and/or subnet mask for the given Enterprise Terminal Server machine:

Updating the installed software requires the termination of all the running virtual desktops (connected or disconnected). These sessions cannot be recovered later.

The cleanest way to upgrade a multi-node environment is to:
1. Initially update the installation on each of the nodes (Terminal Server Node).
2. Then update server's installation.

If the failover cluster is set, update the primary server and the secondary server (order of update is not relevant). After the update, restart both cluster servers to make sure that the cluster interface is created on the primary server.

A step-by-step guide to upgrade a multinode environment is available in the https://www.nomachine.com/all-documents section.

First of all, ensure that the user has a system account on the Enterprise Terminal Server host and on the Terminal Server Node(s) where he/she will run the session. You can create the account by using system tools or by using nxserver commands. Empty password is not supported.

Once the multinode environment is set-up, the Enterprise Terminal Server is ready to go.

The end-user should point the browser on his/her device to:

http://SERVER:4080

Where SERVER is either the name or IP address of the host you want to reach.

E.g., if Enterprise Terminal Server is installed on a host named 'myserver.com', the URL will look like this:

http://myserver.com:4080

Connection will be automatically switched to HTTPS protocol:

https://myserver.com:4443/nxwebplayer

In the login form, the end-user has to provide username and password of his/her system account on the Enterprise Terminal Server host and connect.

TIPS
I	Auto-reconnection is supported: when the connection is lost for whatever reason (including when browser's computer has entered sleep mode), the NoMachine web application will automatically try to reconnect for as long as the user keeps 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.
III	In order to be able to connect over the internet, port 4000 and 4443 must be open between the user's device and server. This is mandatory to allow sessions from the web.

From a client device, where you have already installed a NoMachine package type or the Enterprise Client, run the NoMachine GUI from the programs or applications menu. A wizard will take you through the steps necessary to set-up your first connection, just click on 'Create a new connection'. If you prefer to skip the wizard, click on 'Continue'.

The fastest way to create a new connection is to write the name or IP of the NoMachine host you want to connect to in the text field and click on the 'Press enter to create a new connection' link. This method will use the default NX protocol on port 4000. Otherwise, specify the SSH protocol.

Alternatively, you can click on the 'New' icon next to the white text field to configure the session in more detail.

TIPS
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 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.
III	Connections by NX protocol by default use port 4000. Connections by SSH use port 22. Any of these ports must be open between the user's device and server. This is mandatory to allow sessions from client.

To prevent NoMachine users from storing their credentials, use the EnableCredentialsStoring key in the server configuration file. The accepted values are:
player Only users connected via NoMachine client are enabled to save username and password in the connection file stored on their devices (computer, tablet etc ...)
webplayer Only users connected via browser can choose to save their access credentials. They are stored in the browser's cookie, given that the user's browser has cookies enabled.
both All users, regardless if connected via NoMachine client or via web, can store their credentials.
none Users cannot save their username and password. They will be requested to provide their log-in credentials at each connection.

For example, to allow only users connecting via NoMachine client to store credentials, set in the server configuration file:
EnableCredentialsStoring player

The configuration file for the web player program (which provides the graphical front-end) and the web client program (which manages web sessions) is server.cfg, located in the BaseDirectory/NX/etc directory on Linux: /usr/NX/etc/server.cfg.

Default settings
The Section directive defines settings for the NoMachine server(s) where the web player application will connect. This directive, by default, points to localhost and looks like:

Section "Server"

Name "Connection to localhost"
Host localhost
Protocol NX
Port 4000
Authentication password

EndSection

Name is a label that can be displayed as an alternative to show hostname of the server.
Host is IP or hostname of the NoMachine server host.
Protocol and Port indicates protocol and port that web player will use to connect to the NoMachine server.
Authentication defines the authentication method to be used when connecting by the web: 'password' for password-based authentication (default) or 'private-key' for key-based authentication.

Changing protocol and port
By default when users connect via web, they will use the NX protocol on port 4000. Supported protocols are NX and SSH with system login.

To use the NX protocol (this is the default), set:

Protocol NX
Port 4000

To use SSH protocol and system login, set:

Protocol system
Port 22

Define the authentication method
When connecting by the web and since v. 6.6.8, it's possible to use password-based authentication or key-based authentication (available at the moment only for the NX protocol).

To use password-based authentication (this is the default), set:

Authentication password

To use SSH key-based authentication, set:

Protocol NX
Authentication private-key

TIP

NoMachine uses by default port 22 for SSH protocol on Linux.The default port for NX protocol is 4000. In order to change the port for NX protocol, change the port for the nxd service and restart it. See the paragraph 'Connecting by NX Protocol'. To change the port for connections by SSH it's necessary to modify the listen port for the SSH server on the system.

Showing hostname or a custom label
To display hostname or IP of the Enterprise Terminal Server host when connecting by the web, set the following key. This is the default:

EnableWebConnectionName 0

To display the label set in the Name field of Section "Server" set:

EnableWebConnectionName 1

Hiding the tutorial wizard at web session startup
To not display the tutorial wizard for the menu panel at session startup, set:

EnableWebMenuTutorial 0

and to show it (this is the default):

EnableWebMenuTutorial 1

You can start and stop the NoMachine HTTP server (nxhtd)
from the Server preferences GUI -> Server preferences -> Network services panel. From the NoMachine GUI you can also change the port where the web server will be listening (by default 4080 and 4443 for secure connections).

From command line it's possible to do the following.

Stop, start or restart nxhtd

Automatic restart of the nxhtd service
Each service is automatically restarted at the next boot. You can change the default behavior for the nxhtd service by setting:

The nxserver --startmode command operates on the StartHTTPDaemon server configuration key:

StartHTTPDaemon Automatic

and:

StartHTTPDaemon Manual

Disabling the starting of the NoMachine HTTP server
Edit the server configuration file and remove HTTP from the ClientConnectionMethods key. It should then look like:
ClientConnectionMethods NX,SSH

Then restart NoMachine server to make this change effective:

NoMachine Enterprise Terminal Server is designed to provide a fully integrated service to deploy sessions on the web which doesn't require additional software to be installed or manual configuration. The minimal Apache web server, nxhtd, provides the necessary modules and is pre-configured to work with the web player application.

However, it is possible to run the web player application with an alternative Apache web server. Look for detailed instructions in our Knowledge Base, section Articles, by searching for the 'Apache' keyword: https://kb.nomachine.com .

The implementation of WebRTC support in browser-based remote desktop sessions has inititally been released as beta and must be enabled explicitly by the administrator by editing the server.cfg file.

With the help of a STUN/TURN server for negotiating NAT traversal, peer-to-peer WebRTC communication can be established also when the web session has to be run behind a NAT.

STEP 1: Uncomment and set the AcceptedWebMethods key as follows to enable the use of WebRTC:

AcceptedWebMethods webrtc

STEP 2: If the node machine where the web session will be started is behind a NAT, you need to uncomment the following section in server.cfg:

Section "STUN"

Host hostname
Port portnumber
User username
Password password

EndSection

and provide relevant information to contact a STUN or TURN server. In this last case change Section name to "TURN".

Specific articles can be found in the Knowledge Base, https://kb.nomachine.com.

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

Other 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:

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

HW H.264 encoding is possible when the Enterprise Terminal Server host machine have an hardware accelerated video cards (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.

TIP

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 on 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 contents are 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 suggested for multimedia contents or applications with many graphical effects.

It also may 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 User Interface
in the Server preferences UI -> Performances panel

or in the node configuration file
Edit the node configuration file, uncomment and set the AgentX11VectorGraphics key (previously named 'AgentLightweightMode') to '0' for disabling the the X11 vector graphics mode:
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 https://www.nomachine.com/AR05P00982

The configuration file for the nxserver and nxweplayer/nxwebclient programs is server.cfg. The configuration file for the nxnode program is node.cfg.

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

The Default Configuration
NoMachine Enterprise Terminal Server 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 the server if not otherwise specified.

Installation and upgrade procedures take care of configuring and starting all the necessary services to make NoMachine Enterprise Terminal Server ready to accept and serve users' requests for virtual desktops and custom sessions. The necessary services are configured to be restarted at each reboot of the host machine.

You can stop and start accepting new connections via:

the GUI
from the Server status GUI click on 'Stop the server' and 'Start the server' respectively: this will prevent users from running new connections

or from command line
to disable accepting new connections from the command line, run:

All NoMachine services can be stopped via:

the GUI
all NoMachine services can be stopped by the Server status GUI ('Shutdown the server'). When doing so, you will be asked if services must be started at the next reboot or not. You can restart services also from the Server status GUI ('Start the server').

or from command line.

Stopping all the NoMachine services

Starting NoMachine server and services

Specifying the start mode
It's possible to set the 'start mode' (if services will be started automatically at boot or not) by using:

Stopping and restarting NoMachine server and services

The NoMachine networks services available for NoMachine Enterprise Terminal Server are nxd and nxhtd:

You can stop a single service:

via the GUI
in the Server status -> Server preferences -> Network services GUI. You can choose there also the start mode: if the service must be started automatically at the next boot or not.

or from command line.

Stopping a service

where SERVICE can be:
nxd, the Network Server for accepting connection by NX protocol
nxhtd, the NoMachine web server for web sessions

Starting or restarting a service

Specifying the start mode
By default each service is automatically restarted at the next boot. You can configure that on a per-service basis by running:

Commands above operate on the configuration keys listed below. You can change them manually in the server configuration.

For each session, NoMachine uses ports that are used only locally on the server 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, UDP communication).

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 and select the 'Hide the NoMachine icon in the system tray' option. 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 ballon 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

TIP

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 if you need to permit the connection without explicit authorization.

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

Then restart the server:

By default NoMachine Enterprise Terminal Server broadcasts information to let other NoMachine computers to discover it on the local network. You can disable this feature via:
the GUI
in the Server status -> Server preferences -> "Network services" GUI

or in the server configuration file
set the following key in the server configuration:

EnableNetworkBroadcast 0

Then restart the server to make changes effective:

NoMachine provides an instant messaging tool, named whiteboard which allows also drawing and sharing files with connected users and fast-track access to file transfer. To access it, connect to the user's desktop and from the Monitor (!M icon) in your system tray click on 'Show the whiteboard'. Note that if multiple users are connected at the same time to the same session, they will all see the message.

As an alternative, it's possible to issue a dialog in the connected sessions to show a custom message by sending it from command line.

Sending a message to all running sessions:

It is possible to welcome users when session is started by issuing a greeting message, either only the first time the user logs-in or every time the user connects to the Enterprise Terminal Server. Update the node configuration file by writing the text of your message in any of the following keys:

NodeFirstLoginGreeting "Welcome to your first NX session"
NodeLoginGreeting "Welcome to your NoMachine session"

NoMachine
connections by default use the NX protocol which is its own protocol for secure communication over the network. Encryption in the NX protocol is implemented using OpenSSL TLS/SSL, based on ECDHE-RSA-AES128-GCM-SHA256 as the default cipher suite. ECDHE-RSA-AES128-GCM-SHA256 is an AES (Advanced Encryption Standard) block cipher with 128 bits key in GCM (Galois/Counter Mode). RC4 (ECDHE-RSA-RC4-SHA cipher suite) is used as a backward compatibility when connecting from or to versions 4.0.

When using the NX protocol, NX data can travel on TCP and UDP streams, even at the same time. The client and server can decide dynamically what transport to use, based on the type of data and the network conditions. Client and server negotiate the UDP transport at session startup, after having negotiated the main TCP link. UDP uses symmetric Blowfish encryption, with key negotiated on the secure TCP link. UDP is presently not available when using the SSH tunneling, to ensure that all data goes through the same SSH link, as it was in legacy version 3. UDP protocol can be also disabled.

SSH Protocol
NoMachine Enterprise Terminal Server also provides tunneling of connections using SSH and full integration with any authentication backend supported by the host SSH server.

Authentication methods
These are the authentication methods supported by NoMachine when connections use the NX protocol or the SSH protocol:

Protocols are defined in the ClientConnectionMethods key in the server configuration. They are specified as a comma-separated list of values:

ClientConnectionMethods NX,SSH,HTTP

This key is automatically populated during the installation or the update of the package. It is possible to exclude any of the available protocols to force users to connect by the desired protocol.

For example, to use only NX protocol, set this key to:
ClientConnectionMethods NX

and restart the server to make changes effective:

TIPS
I	If your server supports SSH but it still reports that SSH is not available, check the ClientConnectionMethods key and ensure that the SSH values is set. Then restart the server.
II	Removing 'HTTP' from the ClientConnectionMethods key will disable the starting of the NoMachine HTTP server and prevent connections via web.

Administrators may decide how the user should authenticate on the server by defining which authentication method(s) is/are available. Authentication methods can be set in the server configuration file by editing this key:

AcceptedAuthenticationMethods all

By default all methods are accepted. They can be restricted by providing a comma-separated list of values, they will indicate which authentication method is permitted.

Accepted values for connections by NX protocol are:
NX-password to allow password authentication.
NX-private-key to allow key-based authentication.
NX-kerberos to allow Kerberos ticket-based authentication.

while for connections by SSH protocol:
SSH-system to allow all methods supported for the system login. SSH authentication methods for the system login have to be set on the system for example in the PAM configuration.

For example, to accept key-based and Kerberos ticket-based authentication for the NX protocol:

AcceptedAuthenticationMethods NX-private-key, NX-kerberos

Settings in the client GUI
Users can select the authentication method in their connection settings from the NoMachine GUI in the Advanced panel for the NX protocol and SSH protocol settings respectively.

They correspond to the following options in the client GUI:

Protocol and authentication methods can be set when creating a new connection via client GUI:

or changed later by modifying the connection settings (right mouse click on the connection icon in the client GUI to edit it).

The default setting of NoMachine is to run connections via the NX protocol on port 4000. On server side, the Network Server, nxd, is listening on port 4000. It's mandatory that this port is open between client and server to allow connections by NX protocol.

If you change the listen port for nxd, connecting users will have to specify the new value in their connection settings in the client GUI.

It's possible to modify the port for nxd
from the GUI
in the Server status -> Server preferences -> Network services GUI

or in the server configuration file by editing this key:
NXPort 4000

Restaring the nxd service is necessary to make this change effective:

When NX protocol is used, UDP communication for multimedia is enabled by default. UDP traffic uses a range of ports between 4011 and 4999. These ports must be open between client and server. If they are not available, traffic will fall back to TCP communication. You can change port range, define a comma-separated list of ports or a single port by changing value set for the following key in the server configuration:
UDPPort 4011-4999

Users can disable UDP in their connection settings from the NoMachine GUI in the Advanced panel for the NX protocol settings.

The default port used for the SSH protocol is 22 on Linux. On such platform NoMachine relies on the SSH server installed on the system. If your SSHD is configured to listen on a port different from 22 you need to align the NoMachine server configuration accordingly. Connecting users will have to specify such value in their connection settings in the client GUI.

If your SSH server is listening on a port different than 22, change the SSH port in the NoMachine configuration

in the Server status -> Server preferences -> Network services GUI

or in the server configuration file by editing this key:
SSHDPort 22

Automatic discover of the NoMachine Enterprise Terminal Server host is possible only when the server and the user's machine are on the same LAN. When the user connects over the internet or from a different network, it's mandatory to know the public (or external) IP of the Enterprise Terminal Server.

When the server is behind a firewall, you have to configure the router to forward external port to the nxd service (to use the NX connection protocol), to the SSH server (to use the SSH protocol) and to the nxhtd service (to connect by the web). By default the required ports are TCP ports: 4000 for NX, 4080 and 4443 for HTTP/HTTPS and UDP ports in the 4011-4999 range. Note that users will have to specify the external port in their connection settings in the client GUI.

If the router on the server side supports UPnP/NAT-PMP, you can let NoMachine try to enable port forwarding in the router automatically. External ports will be selected randomly from the 20000 - 30000 range. Also in this case users will have to specify the external port in their connection settings in the client GUI.

For connections by NX protocol, at session startup NoMachine will also try to map UDP ports by using UPnP.

Enabling the automatic port forwarding
Step 1: Set in the server configuration:
EnableFirewallConfiguration 1

Step 2: Specify for which service the port forwarding must be enabled by listing them in the following key:
EnableUPnP NX,SSH,HTTP

Step 3: Specify the port where the NX service will be redirected by editing respectively:
NXUPnPPort ""; SSHDUPnPPort "" and HTTPUPnPPort ""

TIP

To permit only connections by SSH (on external port 20048 for example) and use the automatic port forwarding, set in the server configuration: ClientConnectionMethods SSH EnableFirewallConfiguration 1 EnableUPnP SSH SSHDUPnPPort "20048" and restart the server.

You can enable port forwarding for connections by NX and HTTP/HTTPS protocol also from the GUI
via the Server preferences -> Network services GUI by selecting the service and enter its settings (click on 'Configure'). Then check the Gateway port option.

Retrieving information about UPnP port mapping
When the automatic port mapping is enabled, you can retrieve information about UPnP port mapping, e.g. IP of the gateway device, external port and port mapped by running:

Use of NoMachine DBs can be configured by editing the server configuration. The table below reports which configuration key value has to be set to enable or disable specific behavior as defined in the 'Target' field:

You can manage (create, delete and modify) user accounts by using tools provided by your Operating System or the NoMachine server commands as explained below.

Creating Accounts
The Enterprise Terminal Server is able to handle two types of accounts: system accounts and NoMachine accounts. The latter allows to separate the system password from the NoMachine password by activating EnablePasswordDB, but the system account is still necessary.

Creating a System Account
The system account will be created with the default system settings. The new user will be also added to the NoMachine Users db:

Creating a NoMachine Account
Use this command when the user already has a system account:

TIPS
I	To assign a password different from system password to a system user, enable NoMachine Password DB (EnablePasswordDB 1) in server.cfg.
II	To verify if the user's authentication is based or not on NoMachine Password db:
nxserver --userauth USERNAME
III	If this Enterprise Terminal Server is federated under a Cloud Server, each user must have the same system account on the Cloud Server host and on this Enterprise Terminal Server. Password can be different.

Enabling and Disabling access for a NoMachine User
Prerequisites are:

i) The user has run at least one session or have been added to NoMachine dbs by means of 'nxserver --useradd' command.

ii) NoMachine Users DB is enabled (EnableUserDB 1 is set in server.cfg)

You can enable/disable a user and allow/forbid his access to the Enterprise Terminal Server by running:

Modifying the User's Password
You can modify user's system password by running:

Listing the NoMachine Users
All users who have run at least one session or have been added to NoMachine dbs are stored in the Users db. You can retrieve the complete list by running:

The output of this command provides the following fields:
Redirected to: IP/hostname of the server to which the user's connection is redirected (by means of the 'nxserver --redirect' command when supported).
Trusted for: it shows if the user is trusted.
Screen Sharing: it shows which user has the sharing of their physical screen disabled.
Access: it shows if the user is enabled or not to access the NoMachine system. This works in conjuction with the use of the NoMachine Users DB: when enabled (EnableUserDB 1 in the server configuration), it's possible to enable/disable user's access to the whole NoMachine system.
Forwarded to: this field is applicable only when the server is a NoMachine Cloud Server, so it's always empty in case of Enterprise Terminal Server.

Removing Accounts
To remove an account from the system:

NoMachine Enterprise Terminal Server supports the creation of groups of users with the possibility to set attributes (e.g. the trusted flag) to the group or create profiles rules which apply to all users belonging to the given group (e.g. disable the possibility to print and share disk).

Creating a new group and manage groups' users

Setting the 'trusted' flag to the group
The 'trusted' flag can be specified when creating the group, or later by editing the group. To create or make a group trusted for connections to virtual desktops:

Making the group trusted for specific users' desktops
This feature is available since v. 6.4.6. You can assign the 'trusted' flag and make the group (and all users belongin to that group) trusted only for those desktops owned by a specific user or list of users. For example, if a new group (groupB) should be created and made trusted only for desktop of userA:

Setting profile rules for a group
In order to set a profile rule on a per-group basis, it's necessary to specify the '--group GROUP' option when adding the rule. See the chapter dedicated to Profiles for more information about the available rules. The general format of the command is:

Setting the group's priority level

When the same users belongs to multiple groups, the most permissive settings among those configured for such groups, apply to the user. It's however possible to assign a priority level to each group. This can be done when creating the group or later by editing the group settings. PRIORITY is an integer positive number, for example:

The automatic generation of guests accounts is not enabled by default and must be activated via profile rules. If enabled, the server generates a new system account on demand when the user connects with the 'Login using a guest account' GUI option.

In case of web sessions, set the following key if you need that users connect by the web always as guest users:
EnableWebGuest 1
If this key is disabled, users will have the possibility to choose if log-in with their credentials or as a guest.

Policies to create guest accounts, keep them alive and others can be set by editing the NoMachine server configuration file

It is also possible to define a set of profile rules on a per-guest basis only. Such rules will not apply to other users.

Enabling the automatic generation of guest accounts
Use the following command to create the profile rule for enabling guests on the server:

Then edit the following key in the server configuration:
GuestUserGroup ""
to set the Group Identifier (GID) for NoMachine guest users. The specified GID must already exist on the system.

To enable the login as guest also via web, then set in the server configuration
EnableWebGuest 1

Configuring Guest Accounts (advanced)
The server creates guest accounts by adding a progressive number as a postfix to the base guest name. The range used for incrementing the postfix varies from a minimum and a maximum value. Base name and range for the postfix are configurable:
GuestName guest
BaseGuestUserId 10
GuestUserIdLimit 200

By default the server creates the guest users' homes in the /home directory. To define a different place, edit: GuestUserHome /home

A guest account remains valid for 30 days, but you can set a different time of expiry:
GuestUserAccountExpiry 2592000 (This value has to be set in seconds)

A further configuration key define the maximum number of sessions a guest can run on this server before the account expires (by default 5):
GuestUserConnectionLimit 5

While the following key defines for how long (in seconds) a guest can run the session before the account expires. By default the guest session is never terminated (the key is set to 0):
GuestConnectionExpiry 0

When the account expires, the server by default doesn't remove the guest's home. To remove also guest's home, set:
EnableGuestWipeout 1

Guest users can disconnect their virtual desktops and reconnect them later. To disabled the possibility to reconnect the session and force the session to be terminated when the guest user close it, set:
GuestUserAllowSuspend 0

To limit the number of concurrent guests on this server (by default 10), use:
GuestUserLimit 10

Additionally, it's also possible to allow the server to set disk quota for guests by setting:
EnableGuestQuota 0
and configuring the following keys according to your needs:
GuestQuotaProtoname protoguest
GuestQuotaInodeSoftlimit 0
GuestQuotaInodeHardlimit 0
GuestQuotaBlockSoftlimit 0
GuestQuotaBlockHardlimit 0
GuestQuotaInodeGracePeriod 0
GuestQuotaBlockGracePeriod 0
GuestQuotaFilesystems all

Listing or Removing Guests To retrieve information about the existing guest accounts, included their time of expiry, use:

TIP

Guest users don't know their username and password and cannot therefore unlock the remote screen if screen locking it's enabled. Be sure to disable screen locking if you want to let guest users to connect to the remote desktop.

By default, NoMachine allows the running of sessions as privileged system user ('root' or 'sudo' on Linux). You can however configure the NoMachine Server to disallow it. Do it by disabling the following server configuration key:

EnableAdministratorLogin 0

To re-enable the possibility to log in as root or administrator, set:

EnableAdministratorLogin 1

By default when the connecting user is different from the owner of the virtual desktop, the desktop owner has to authorize the user for the connection.

It is possible to define in advance a number of trusted users who don't need the specific owner's permission to connect to virtual desktops owned by a different user.

In order to create a list of trusted users, administrators should use the nxserver commands for creating and editing users. These commands provide the --trusted option to define if the user is trusted for connections to the virtual desktop or not.

To create on the system a new trusted user for virtual desktops:

Since v. 6.2, it's possible to make the user trusted for a specific node or a list of nodes:

To make a user trusted for specific users' desktops
This feature is available since v. 6.4.6. You can assign the 'trusted' flag and make the user trusted only for those desktops owned by a specific user or list of users. For example, if a new user (userB) should be created on the system and made trusted only for desktops of userA:

To list only trusted users:

Each session on the same server is uniquely identified by a session id (which can look like: B253864E822F5A235825F3AB8853AF00) and a display id (e.g.,1002).

A session on the NoMachine Enterprise Terminal Server can be in any of the following statuses:
Connected - when it's connected to the remote display.
Disconnected - this status is available only for virtual desktop sessions and custom sessions. A session is marked as disconnected when it's disconnected from the remote display. A disconnected session can be reconnected at any time even from a different machine (migration). While a session is disconnected, applications on the remote server stay running.
Finished - the session has been closed in a clean way and all NoMachine processes have been shut-down smoothly.
Failed - any of the NoMachine processes has failed to start or it has been "un-cleanly" terminated.
Transitional statuses are Connecting, Disconnecting and Terminating.

NoMachine Enterprise Terminal Server is able to manage different types of sessions, named internally as in the table below. You can see the complete list of supported session types by running:

Session types supported by the Enterprise Terminal Server and their descriptions are:

You can monitor sessions from command line tools. Below are the server commands to be run from xterm or console.

Listing Running Sessions
To list all the running sessions, their display, session owner, remote IP of the connected client, session ID and session host:

The number of active connections on the server corresponds to the number of sessions in status Connected. Session status is shown in the output of session history command.

Session History
History is preserved for a certain amount of time as set in the server configuration (SessionHistory key). To see the complete list of sessions, including those that have been cleanly terminated or failed, run:

Debugging a Failed Session with Session History
If a session is marked as failed in the session history output, the following command should provide information about the reason of the failure. Since v. 6.7 the output of the following commands has been extended to provide a short report helpful for a preliminary debug of the problem:

Retrieving Statistics about Sessions with Session History
This feature is available since v. 6.7. It elaborates a number of information about sessions, contained in the current session history. For example the number of sessions started, terminated, running and failed and their average startup time. The command to retrieve statistics is:

Clearing Sessions History
You can reset the history backlog by running the following command.

Configuring the Session History Backlog
Data is preserved for 30 days. You can modify that in the server configuration file by uncommenting and setting a different value for the following key:
SessionHistory 2592000

This key accepts the following values:
< 0 Never delete data from NX session history.
0 Disable NX session history.
> 0 Keep data in session history for this amount of seconds.

Disconnecting a Virtual Desktop Session from Command Line
You can disconnect a session, if it's a virtual desktop one, by running:

TIP

Take SESSIONID or DISPLAYID from the output of the 'nxserver --list' command, they are the 'Session ID' and 'Display' column respectively. The same output shows also the user's name.

Disconnecting or Terminating Virtual Desktops Automatically
To disconnect a virtual desktop or custom sessions after a certain time of inactivity, uncomment and set a proper timeout value, in seconds, in the following node configuration key. For example, if you want to terminate sessions after 10 minutes of inactivity you need to set:
DisplayServerExtraOptions "-timeout 600"

If the NoMachine display agent doesn't receive any input from the user in the given timeout, it will either disconnect or terminate the session. Termination of the session will be carried out if the session is not persistent or no X application is connected to the display. Otherwise the agent will disconnect the session so that the X applications will be left running.

Note that the DisplayServerExtraOptions key is only for virtual desktops or custom sessions with X11 vector graphics enabled (default).

For web sessions, sessions connected to a virtual desktop (sharing of the virtual desktop), virtual desktops with X11 vector graphics disabled and connections to the physical desktop, set instead:
DisplayAgentExtraOptions "-timeout 600"

Terminating the Session from Command Line
To terminate a virtual deskto or custom session:

Terminating Automatically Virtual Desktop/Custom Sessions in Status Disconnected
It's possible to specify for how long the server has to keep alive virtual desktops in the disconnected status. When the time has expired, the server will terminate virtual desktops if no user is connected there. To let the server terminate a disconnected virtual desktop after XXX seconds, edit the server configuration file, uncomment and set the timeout value (XXX) expressed in seconds in the following key:
DisconnectedSessionExpiry XXX

For example, by setting:
DisconnectedSessionExpiry 600
a virtual desktop will terminate after ten minutes provided there is no activity.

Terminating Automatically Virtual Desktop/Custom Sessions when the Maximum Number is Reached
To terminate a disconnected session when the maximum number of virtual desktops (see 'Limiting the Number of Virtual Desktops' below) is reached and make room for a new virtual desktop or custom session, enable the following key in the server.cfg file:
EnableAutokillSessions 1

Limiting the Number of Virtual Desktops or Custom sessions
You can set a limit for the number of virtual desktops provided that such limit does not exceed the number of connections allowed by the server license value (it's the 'Virtual Desktops' field in the server.lic file). NoMachine Enterprise Terminal Server allows up to four concurrent virtual desktops.

For example to configure the server to allow only two concurrent virtual desktops, edit the server configuration and set:
VirtualDesktopsLimit 2

You can also specify how many virtual desktops a single user may run. For example, to allow 1 connection per-user, uncomment and set the following key in the server configuration file:
VirtualDesktopsUserLimit 1

A Practical Example
Limit the number of virtual desktops to three and keep alive a virtual desktop (inactive & disconnected) for one day. If a new virtual desktop is requested, the server will terminate the oldest virtual desktop in status disconnected to make room for the new session.
VirtualDesktopsLimit 3
EnableAutokillSessions 1
DisconnectedSessionExpiry 86400

Automatic Disconnection of Users
The automatic disconnection is a server configuration to rule the server behavior when the limit of users is exceeded and a new user is requesting to connect.
Current options are:
enabled (1): the server will automatically disconnect the user to make room for the new user.
disabled (0): the server will issue a pop-up message before disconnecting the user. The current user can accept or not to
disconnect itself. If no choice is made, the server will automatically disconnect this user and let the incoming user to connect.

The automatic disconnection applies when the maximum number of available connections to the desktops or the maximum number of available virtual desktops is exceeded.

To enable the automatic disconnection set the following key in the server.cfg file:
AutomaticDisconnection 1

To let the connected user decide or refuse to disconnect, set:
AutomaticDisconnection 0

Disabling persistent virtual desktops
Users may be forced to terminate their virtual desktop session by setting in the server configuration:
DisablePersistentSession all

In this way when the user closes the virtual desktop, the session is terminated instead of being disconnected. This server configuration key accepts also a list of comma-separated usernames and will be applied to the specified users. Non persistent sessions cannot be reconnected.

Pre-requisite to connect by NoMachine is that a desktop environment is installed on the system even if the host is headless or it's not started in graphics mode.

During its installation, NoMachine detects the default desktop environment set on the system and configures the node accordingly. Path and command to start the system desktop environment is defined in the node configuration file by the DefaultDesktopCommand key. The Enterprise Terminal Server is able to detect GNOME, Unity, KDE and LXDE and Xfce (since NoMachine v. 6.7). If you have a different desktop environment, it's necessary to edit the DefaultDesktopCommand key accordingly.

For example to run MATE:
DefaultDesktopCommand "/usr/bin/mate-session"

or to run Pantheon:
DefaultDesktopCommand "/usr/bin/gnome-session --session=pantheon"

If there are multiple desktop environments installed, you can specify in the same key the desktop to be launched. For example if you have KDE, GNOME and Xfce installed installed on Ubuntu 16.04 and want users to be able to run new virtual KDE desktops, set the configuration key to:
DefaultDesktopCommand "/etc/X11/Xsession startkde"

If you want they create new GNOME virtual desktops instead, set:
DefaultDesktopCommand "/etc/X11/Xsession 'gnome-session --session=gnome'"

or for creating Xfce virtual desktops:
DefaultDesktopCommand "/etc/X11/Xsession startxfce4"

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If you want to let users choose between creating new KDE or GNOME virtual desktops (given that they are both installed) set desktop=1 in the ConnectPolicy key in the server configuration. With this key set, the server uses the following keys (in node.cfg) to start respectively KDE and GNOME virtual desktops: CommandStartKDE and CommandStartGnome.

RDP sessions are encapsulated inside a virtual desktop session and they use the RDP client. So, prerequisite is that this RDP client (by default rdesktop) is installed on the host machine where the NoMachine RDP virtual desktop will be run, this is likely to be any of the Terminal Server Node hosts.

Note that behaviour of RDP sessions is strictly related to features supported by the RDP client. For example, running a Windows application as a single application is possible only if the version of the RDP client supports it.

Support for RDP sessions is not enabled by default in NoMachine Enterprise Terminal Server. To enable it, please follow instructions at: https://www.nomachine.com/AR07J00645

VNC sessions are encapsulated inside a virtual desktop session and they use the VNC client. So, prerequisite is that this VNC client (by default vncviewer) is installed on the host machine where the NoMachine VNC virtual desktop will be run, this is likely to be any of the Terminal Server Node hosts.

Note that behaviour of VNC sessions is strictly related to features supported by the VNC client.

Support for VNC sessions is not enabled by default in NoMachine Enterprise Terminal Server. To enable it, please follow instructions at: https://www.nomachine.com/AR10K00720

The server configuration provides a number of keys that can be activated to execute a custom script upon a certain event. According to the event, a number of parameters can be specified for each script. In a similar way, a number of keys is present in the node configuration file to allow to execute a custom script on a certain NoMachine node event. In both cases and according to the event, a number of parameters can be specified for each script.

(*) 'main session id' and 'main session type' parameters are available only when the user connects to an already running virtual desktop (session shadowing). They indicate respectively the id and type of the session to which the user is connected with his/her own session qualified by 'session id' and 'session type'.

A further key in the node configuration file (available since v. 6.3.6), allows to run a custom script triggered on change resolution events (resize of the remote screen). The related key is:
UserScriptAfterRemoteResize

Note that order of parameters is relevant. For example, a custom script to be run on node event 'UserScriptBeforeSessionStart' should use the $2 variable to retrieve username and $4 to retrieve display.

Pre-requisites to run custom scripts
Custom scripts must be executable. Custom scripts set-up in server.cfg are common to all the users who are accessing the server and are executed by the nxserver program. Since nxserver is running as the nx user, you have to grant this user the necessary permissions in order to execute the custom script.

Custom scripts set-up in node.cfg are executed by the nxnode program, which is run as the connected user. Place the script in a directory that is accessible by the node, i.e. accessible by the connected user(s).

By default if the execution of the scripts fails, the nxserver and nxnode will terminate. This means that the user's session will not start. You can override this behavior by forcing exit 0 inside the custom script and let the session start even if the custom script is failed.

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If NoMachine Enterprise Terminal Server is federated under a Cloud Server consider that custom scripts have to be placed in server.cfg or node.cfg file on the Enterprise Terminal Server host, not on the Cloud Server.

Multiple connections to a virtual desktop
By default users can connect to their virtual desktops and to virtual desktops owned by other users. When the desktop owner is different from the connecting user, he/she is always required to authorize the incoming request for connection. Authorization is not requested when the incoming user and the desktop owner are the same. This allows different users sharing the same instance of the virtual desktop and access all applications and resources interactively or in view-mode only. This feature is suitable for collaborative sessions and desktop sharing.

Request for desktop owner's authorization and interaction level can be configured
via the GUI
You can configure how users will connect to a desktop owned by another user from the Server preferences GUI -> Security panel. You can basically determine if users can connect or not without asking the desktop owner's permission and if users will be able to interact with the desktop. Allowing connections in interactive mode grants the user full access to the desktop resources and applications. View-only mode is suggested for example when making presentations or teaching a lesson.

or in the server configuration file
besides using the graphical tools, you can configure the server by editing the server configuration file, uncommenting and setting a proper value for keys as illustrated in the following paragraphs.

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I	Configurations made from the GUI apply to connections to physical and virtual desktops. If you want to set a separate configuration for these desktops, you have to edit the server configuration manually.
II	Rather than allow all users to connect without virtual desktop's owner authorization or click accept for every single user which would like to connect, it is possible to define in advance a number of trusted users who don't need the specific owner's permission.
III	When the Enterprise Terminal Server is federated under a Cloud Server, each user must have the same system account on the Enterprise Terminal Server host and on the Cloud Server host. Password can be different.

Connect to the physical desktop

NoMachine Enterprise Terminal Server supports the screen blanking feature: when active, the local user will see a black screen on the physical monitor while somebody is connected from remote to the physical desktop. Operations made on the physical screen are not shown and the local user cannot interact with the desktop until the remote user logs-out. Control is given back to the local user once the remote user has logged off. Screen blanking is available for physical hosts, it is not supported on virtual machines since it has effect on the physical monitor

You can activate the screen blanking feature on the Enterprise Terminal Server host machine
via the GUI:
in the Server preferences GUI -> Security panel select the 'Blank the physical screen when somebody connects' option.

or in the server configuration file.
Uncomment and set the following key:
EnableScreenBlanking 1

To disable the screen blanking, set:
EnableScreenBlanking 0

In both cases then restart the server to make this change effective:

The screen blanking feature can be used in conjunction with the automatic lock of the remote screen: even if the user didn't lock the screen before disconnecting by NoMachine, when the screen is unblanked the system lock screen should be activated automatically to keep the remote desktop protected even if the computer is running unattended.

You can enable the automatic remote screen lock from the GUI:
in the Server preferences -> Security panel select the 'Lock the physical screen on disconnect' option

or in the server configuration file, server.cfg.
Uncomment and set the following key:
EnableLockScreen 1

To disable the automatic screen lock, set:
EnableLockScreen 0

Then restart the server to make this change effective:

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For versions previous than v. 6.1: The option to manage the screen blanking from the server User Interface was named 'Lock the physical screen when somebody connects' and the server configuration key was: EnableScreenLock. The possibility to automatically lock the remote screen when the user disconnects was not available.

By default users can connect to virtual desktop sessions owned by a different user. To forbid this capability, set in the server configuration file:
VirtualDesktopSharing 0

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This setting disables also the listing of other user's virtual session in the client GUI.

To forbid users to interact with the desktop once connected set in the server configuration:
VirtualDesktopMode 0

In this way, the connected user will access the virtual desktop in view-only mode.

To allow interaction instead, ensure to have:
VirtualDesktopMode 1

To request for the explicit authorization of the desktop owner before connecting the user, be sure that the following key is set in the server configuration:
VirtualDesktopAuthorization 1

Users trusted for virtual desktops, and by default also system administrators and NoMachine administrators, will be able to connect without the need for the desktop owner's approval.

Since v. 6.4, it's possible to request the owner's authorization also for administrators. To configure this, set:
VirtualDesktopAuthorization 2

To allow users connecting to the virtual desktop without explicit permissions, set:
VirtualDesktopAuthorization 0

Settings above apply to all users.

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To restrict the access without owner's authorization to given users, set: VirtualDesktopAuthorization 0 in the server configuration and edit each user to set the 'trusted for virtual' flag:

nxserver --useredit USERNAME --trusted virtual

By default, connections to the physical desktop are enabled and require the desktop owner's permissions.

Users trusted for physical desktop, system administrators and NoMachine administrators will be able to connect without the need for the desktop owner's approval.

Limit connections to the physical desktop
Connections to the physical desktop can be fully disabled by setting in the server.cfg file:
PhysicalDesktopSharing 0

It's possible to limit connections to the physical desktop to special users (system administrators, NoMachine administrators and trusted users and the desktop owner). They can connect without authorization, even when the server is configured to request it. This configuration can be helpful for example when the computer run unattended. Set:
PhysicalDesktopSharing 2

To allow all users connect to the physical desktop, set:
PhysicalDesktopSharing 1

Limit user's interaction with the physical desktop
To forbid users to interact with the desktop once connected set in the server configuration:
PhysicalDesktopMode 0

In this way, the connected user will access the physical desktop in view-only mode.

To allow interaction instead, ensure to have:
PhysicalDesktopMode 1

Enable or disable requesting the desktop owner's authorization
To request for the explicit authorization of the desktop owner before connecting the user, set in the server configuration:
PhysicalDesktopAuthorization 1

System administrators, NoMachine administrators, trusted users and the desktop owner will be still able to connect without authorization.

Since v. 6.4, it's possible to request the owner's authorization also for administrators. To configure this, set:
PhysicalDesktopAuthorization 2

To never request the desktop owner's authorization and allow all users connecting to the physical desktop without explicit permissions, set:
PhysicalDesktopAuthorization 0

System administrators
A privileged system user has to be defined by means of system tools.

The Enterprise Terminal Server allows by default administrative users to connect. You can disable it by setting in the server configuration:
EnableAdministratorLogin 0

To re-enable the possibility to log in as root or administrator, set:
EnableAdministratorLogin 1

NoMachine administrators
Permissions as NoMachine administrator are totally indipendent from system privileges and apply only to NoMachine. A NoMachine administrator, for example, can create a NoMachine infrastructure by adding server hosts to a central server. To create a new user on the system with NoMachine administrative permissions, execute:

NoMachine trusted users
To allow a restricted number of users to connect to the physical desktop without explicit authorization, assign the 'trusted' flag to a new system user. They don't have further privileges, neither on the system nor in NoMachine. To create a new user on the system trusted for NoMachine physical desktops, execute:

Since v. 6.2, it's possible to make the user trusted for a specific node or a list of nodes:

User's ability to disable accepting connections to the physical desktop
By default, the owner of the physical desktop, either sit in front of the computer or connected to the physical desktop via NoMachine, has the possibility to switch off/on the sharing of the screen at any moment.

This can be done via the NoMachine Monitor (click on the !M icon in the system tray to open it) and the 'Accepting connection is enabled/disabled' item in the menu.

When 'Accepting connection' is disabled, nobody can connect to that desktop by NoMachine. This setting lasts until the desktop owner changes it again. It persists also when the user physically is logged-out or closed the NoMachine connection. It's therefore strongly advisable to be very careful when disabling accepting connections from remote, since it will be no longer possible to reconnect to the desktop via NoMachine once the current session is closed.

As administrator, you can override user's settings and forcibly enable or disable the screen sharing for the given user. The user, however, will be still able to change it from the !M Monitor menu:

The Enterprise Terminal Server permits users to access and share their devices and resources from local to remote and vice-versa. Disks, printers, USB devices and more can be connected inside the session to easily access them from both client and server side. At present device sharing is not available with web sessions and requires to connect by NoMachine client.

Two-ways copy and paste is fully supported. Web sessions implements the NoMachine virtual clipboard provides for copying text from/to the session running in the browser and the local computer.

Download/upload files from the session to the local computer and vice-versa is also fully supported in client and web sessions, as well as drag and drop of a file from remote to local and from local to remote.

By default device sharing, copy&paste and file transfer are always permitted. You can however completely disable any of these services or disable it only partially, for example to prevent users from sharing their local printer in the NoMachine session but permitting them to use the remote printer.

NoMachine implements a self-contained infrastructure for making available physical and logical devices over the network from local to remote or vice-versa.

The NoMachine infrastructure for device sharing ensures that all services work out of the box without the need for any additional change or configuration. It is possible to connect disks, printers, USB devices, network port and smartcards.

Connecting devices is supported only by NoMachine client (web sessions don't support that). Devices can be connected through the NoMachine menu within the session (ctrl+alt+0 to open it). Connected devices can be disconnected during the life of the session and reconnected later. If option 'Export this deviceName at session startup' is checked in the menu panel, this device is automatically reconnected at the next session start-up.

Disabling device sharing
You can disable selectively the possibility to share a device

from the GUI
in the Server GUI -> Devices panel

or in the node configuration file
by editing the corresponding keys. The manual configuration permits also to limit only oneway of service, for example forbid to connect a local printer to remote. The next paragraphs deal with manual node configurations in detail.

The available devices are:

NoMachine allows access to local and remote file systems from within the session through the SSHFS file-sharing protocol and by means of FUSE, a technology to implement a fully functional filesystem in a userspace program.

Connected folders and disks can be disconnected during the life of the session or left as they are.

By default, all disks from the server are available to be connected to the end-user's machine. However you can specify a set of disks and folders by editing a proper value for the DiskSharingList key in the node configuration file. The default value is: all. Alternatively, you can specify a list of comma-separated directories. Note that $(HOME) and $(USER) are accepted values.

Disks from the end-user's machine can be connected on the server in 'Public' or 'Private' mode.

Connecting public disks
Disks from the end-user's machine can be connected on the server in 'Public' or 'Private' mode.
By default public disks are exported from player to "$(PUBLIC)" directory on the server, where $(PUBLIC) is: /media on Linux.

You can specify a different path by un-commenting and editing the DiskSharingPublicBasePath key in the node configuration file.
Note that $(USER) is an accepted value that can be also concatenated to specify the path to a directory, for example "/tmp/$(USER)".

The target directory must exist on the system!

Disabling Disks' Connection
To forbid disk and filesystem sharing, uncomment and set a proper value for the EnableDiskSharing key in the node configuration file:
client The filesystem on the client can be connected to server side and accessed from the session.
server The filesystem on the server can be connected to the end-user's machine and accessed through the whole life of the session.
both Client and server filesystem can be connected to remote and local sides respectively.
none Neither client or server filesystem can be connected.

For example, to forbid connecting disks from remote to local side, set in the node configuration:
EnableDiskSharing client

The printers sharing infrastructure integrates client-side printers with the server-side printing subsystem and vice-versa. Printers available on the client machine can be shared and used within the session as well as printers on the server side which can be made available on the end-user's machine.

Connected printers can be disconnected during the life of the session or left as they are. In this case, they are automatically shared at the next session start-up.

On Linux this service uses the CUPS infrastructure present on the system. With CUPS 1.4 or later, to ensure that users are able to connect a printer from local to their NoMachine session on Linux , it's necessary that the user already belongs to the CUPS System Group on the NoMachine server host. That's because, to add a printer to the CUPS system, the 'lpadmin' command line tool has to be executed by a user who belongs to the CUPS's System Group, which can be for example 'lpadmin' on Ubuntu, 'sys' on Fedora, RHEL and CentOS distributions.

Disabling Printers' Connection
To forbid printer sharing it is necessary to uncomment and set a proper value for the EnablePrinterSharing key in the node configuration file:
client Printers on the client can be connected to server side and made available within the session.
server Printers on the server can be connected to the end-user's machine.
both Client and server printers can be connected to remote and local sides respectively.
none Neither client or server printers can be connected.

For example, to forbid a server-side printer to be connected to the end-user machine, set in the node configuration:
EnablePrinterSharing client

This service creates a USB tunnel between client and server to forward devices over the network such as hard disk, web cams, barcode readers, and pen drives from local to remote desktops and vice-versa.

Disabling USB Forwarding
To forbid USB device sharing it is necessary to uncomment and set a proper value for the EnableUSBSharing key in the node configuration file:
client USB devices on the client can be forwarded to server side and made available within the session.
server USB devices on the server can be connected to the end-user's machine.
both Client and server USB devices can be connected to remote and local sides respectively.
none Neither client or server USB devices can be connected.

For example, to avoid that users can forward a USB devices from the server to its own machine, set in the node configuration:
EnableUSBSharing client

NoMachine can create virtual network interfaces and establish a bridge between local and remote sides or vice-versa to provide transparent access to network resources.

This service allows access to any of the default network servers like Samba, CUPS, FTP, SSH and Telnet or any other type, for example a MySQL server.

Connecting a Samba server allows access to resources on that server host via the SMB/CIFS protocol. Connecting a local CUPS server to the remote side allows mounting of printers (local to the user) on that remote CUPS subsystem so that files can be printed on the remote side via the IPP protocol.

Some typical examples of usage:
Print to remote printers from the session
If you have a Linux or Mac machine you can add the local CUPS server via the player toolbar. Choose to add a local server and select CUPS. In this way all printers that are available on your side will be available also on the server and you can print all your documents via the native CUPS (IPP) protocol.

Access a remote host not in your Network Neighborhood
If the remote host has a Samba server, you can add it via the player toolbar. Choose to add a remote server and select Samba as server type. Once that Samba server is added, the remote host shows up in your local Network Neighborhood. You can then connect to remote folders via SMB/CIFS protocol as if that host was in your local network.

Make available a client side HTTP server
You can add your local HTTP server via the player toolbar and make it available on the remote host where your session is running. In this way you can develop and test your web application directly inside the session, without the need for sharing or moving files from remote to local.

Connect to MySQL server behind a firewall
You can choose to add a remote server via the player toolbar. Select 'Custom' and specify MySQL and the port for the MySQL server, by default 3306. Once done, you can connect to that MySQL server via the MySQL client installed on your PC.

Disabling Network Port Forwarding
To forbid network server sharing it is necessary you uncomment and set a proper value for the EnableNetworkSharing key in the node configuration file: client Network servers on client side can be connected and made available within the session.
server Network server on the server side can be connected and made available on the end-user's machine.
both Network servers from client and server side can be connected to remote and local sides respectively.
none Neither client or server side network servers can be connected.

For example, to forbid users from connecting their local ports to the server, set in the node configuration:
EnableNetworkSharing server

When the smartcard reader plugged into the enduser's host is forwarded to the server host, the smartcard authentication is made available inside the session. It can be integrated on with Kerberos Ticket system for example for implementing single sign-on (SSO).

Disabling Smartcard readers' Forwarding
You can enable or disable support for smarcard forwarding by uncommenting and setting the EnableSmartcardSharing key in the node configuration to 1 or 0 respectively.

To disable it set in node configuration file:
EnableSmartcardSharing 0

By default users can copy and paste from local to the session and vice-versa.

You can configure the server to limit such operations by setting proper values in the configuration file as explained below.

Limiting copy & paste operations
To forbid copy & paste partially or totally, uncomment and set a proper value for the EnableClipboard key in the server configuration file:
client Content copied on the user's side can be pasted inside the session.
server Content copied inside the session can be pasted on the user's side.
none No copy and paste operations are allowed.
both Two-way copy and paste operations are allowed.

Limiting the Clipboard Buffer
By default, the clipboard buffer is unlimited. If you want, for example, to limit the clipboard buffer to 4MB, you have to uncomment and set the following key (value is espressed in bytes) in the node configuration file:
ClipboardBufferLimit 4194304

When a user is connected to the desktop, they have the possibility to transfer files by using the Connection Monitor tool from the system tray within the session. The user can transfer a file from their own PC to the remote host where the session is running and vice-versa. If multiple users are connected, each of them can send a file to a specific user or to all connected users. Drag and drop of a file is also supported

You can manage file transfer
from the GUI
In the Server GUI -> Transfers panel

or via node configuration.

Disabling File Transfer
To forbid file transfer you have to uncomment and set a proper value for the EnableFileTransfer key in the node configuration file:
client Files can be transferred from client machine to the server.
server Files can be sent from the server to clients.
both Client and server files can be transferred on remote and local respectively.
none Neither client or server files can be transferred.

For example, to forbid users from transferring a file from the server to their PC:
EnableFileTransfer client

On Linux, NoMachine audio framework is integrated with PulseAudio sound server. If PulseAudio is not available on the system, NoMachine is able to use ALSA (Advanced Linux Sound Architecture). This is automatically managed by the NoMachine server so that multimedia support can work out of the box without the need for any configuration. If both PulseAudio and Alsa are available, the administrator might want to configure the node to use one or the other.

Disabling or Setting Audio Support
To disable audio and microphone support, uncomment and set the AudioInterface key to 'disabled' in the node configuration file:
AudioInterface disabled

On Linux it is possible to define whether PulseAudio Server or ALSA has to be used by setting AudioInterface key to 'pulseaudio' or 'alsa' respectively. For example:
AudioInterface pulseaudio

NoMachine permits to record in a video all activities made inside the session or on the desktop. To start the recording of the session, users should open the NoMachine menu inside the session (ctrl+alt+0) and click on the 'Recording' button icon to access the Recording panel. From this panel it's possible to open the recording bar, change audio and video quality and open the recording directory to access all recorded files. Session recording is not available with sessions on the web.

To register activities made on the desktop, start the recording from the !M icon menu in the system tray of the Enterprise Terminal Server host and show the Recording bar from there. Desktop activities can be registered on the physical desktop without the need to be connected by NoMachine.

Recorded files are saved by default in WebM format and can be played back directly with NoMachine or any other player supporting that format. Video streams can be encoded only with VP8 or H.264 when supported. Recorded files are saved by default on the user's device in the NoMachine directory under the 'Documents' directory.

Disabling session recording
To prevent users from recording their session activities, edit the node configuration to set:
EnableSessionRecording 0

Disabling desktop recording
To prevent users from recording desktop activities, even when physically logged into the Enterprise Terminal Server host, edit the node configuration to set:
EnableLocalRecording 0

A profile is defined by a set of rules which restrict the default behavior. Rules can be set for all users (as an alternative, the same result can be achieved via configuration files) or can be applied on a per-user basis. For example you can create rules to disable copy&paste, or limit device sharing etc ...

Support for profiles is enabled by default. It can be disabled by creating the following rules. Disabling profiles doesn't delete the existing rules:

Some definitions

Default profile of NoMachine Enterprise Terminal Server
Until the administrator defines a set of rules, the server relies on its default profile, which allows all the supported functionalities, except for automatic generation of guest accounts that must be enabled explicitly.

Resources Availability
The default profile of the server is based on the list of resources available on that host. Setting profile rules is like creating a subset of available resources. When the user logs in to the system, NoMachine Server verifies what is allowed for that user by comparing available resources and the set of profile rules.

To retrieve the list of available resources:

Allow and deny class types
A rule to allow or deny a class type (e.g. forbid a session type) or set a behavior (e.g. limit the bandwidth usage) has to be explicitly set, otherwise the server continues to rely on its default behaviour.
If you need, for example, to deny all features except one, you may deny all features for the whole system and add a rule to allow only this feature.

The general format of the command to create a profile rule is:

Create a new group of users, add/remove users, delete a group of users

Create a new group of nodes, add/remove nodes, delete a group of nodes

You can retrieve the list of session types supported by this server by running:

Then you can create the rule to forbid any of the supported session types. For example forbid user 'nxtest01' (this has to be an existing user!) to connect to virtual desktops running on that host (session shadowing):

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Rules for session types: unix-gnome and unix-kde works only if server has the ConnectPolicy key enabled with the desktop=1 option set. With this settings, users are entitled to choose between starting a GNOME or a KDE desktop (if both are available on the system). Otherwise the default desktop environment set on the system is started.

OPTIONS can be:
--system to set the rule on a per-server basis. The rule will be applied to the whole NoMachine system and to every user accessing it. This is the default and can be omitted.
--user USERNAME to set the rule on a per-user basis (USERNAME). The rule will be applied to the specified user only.
--group GROUP to set the rule for the specified GROUP of users
--guest to apply the rule to all guest users. This will not affect other users.
--node NODE:PORT, to apply the rule to the given node. NODE:PORT is the name of the node as it appears in the output of the 'nxserver --nodelist' command.
--nodegroup GROUP, to apply the rule to all nodes in the given group.

Benefit of using profile rules instead than configuration keys is to gain more flexibility thanks to the possibility of setting the rule on per-user/group basis.

It's strongly advisable to not mix the two methods, use of profile rules and of server configuration.

The following directives, instead, are accepted:
Client IP Redirected to:
192.168.1.1 server a
192.168.1.* server b
192.168.*.* server c
The star wildcard can also be used when specifying hostnames. For example: *.nomachine.com

OPTIONS allow to define the criteria to be applied for log rotation. Accepted values are:
--timeinterval INTERVAL set the frequency of rotation. INTERVAL can be specified in seconds or by using any of these keywords: Daily or Weekly or Monthly or Yearly

--minsize MINSIZE use it in conjunction with --timeinterval to rotate the file only when it exceeds the given size. MINSIZE is by default in KB (K). Specify M or G to provide the size in MB or GB respectively.

--size SIZE apply rotation when the file exceeds the given size, regard- less of time frequency. SIZE is by default in KB (K). Specify M or G to provide the size in MB or GB respectively.

--compress yes|no compress or not the rotated file as gz archive (by default, rotated files are compressed).

--destination PATH specify where rotated files have to be stored. By default they are stored in the /usr/NX/var/log/logrotate directory.