Microsoft Remote Desktop On Linux



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  • Mar 20, 2019 The Remote Desktop Protocol is an intuitive and responsive way to control a Windows 10 computer from another computer on your network. You can do this from another Windows 10 PC, or from a Linux.
  • Students can use Microsoft Remote Desktop (RDP) to connect to their Linux VMs after their instructor sets up their lab with RDP and GUI packages for a Linux graphical desktop environment (such as MATE, XFCE, and so on). Here are the steps to connect: On the tile.

As it prepares Windows 11, Microsoft has been laying the groundwork for such a radical release. I’ve long toyed with the idea that Microsoft could release a desktop Linux. Now I’ve started.

This article shows you how to do the following tasks:

  • Enable graphical remote desktop sessions for a Linux VM
  • How to connect to a Linux VM using RDP (Remote Desktop Protocol) or X2Go remote desktop clients

Set up graphical remote desktop solution

When a lab is created from a Linux image, SSH (Secure Shell) access is automatically configured so that the instructor can connect to the template VM from the command line using SSH. Likewise, when the template VM is published, students can also connect to their VMs using SSH.

To connect to a Linux VM using a GUI (graphical user interface), we recommend using either RDP or X2Go. Both of these options require the instructor to do some additional setup on the template VM:

RDP Setup

To use RDP, the instructor must:

  • Enable remote desktop connection; this is specifically needed to open the VM's port for RDP.
  • Install the RDP remote desktop server.
  • Install a Linux graphical desktop environment (such as MATE, XFCE, and so on).

X2Go Setup

To use X2Go, the instructor must:

  • Install the X2Go remote desktop server.
  • Install a Linux graphical desktop environment (such as MATE, XFCE, and so on).

X2Go uses the same port that is already enabled for SSH. As a result, no extra configuration required to open a port on the VM for X2Go.

Note

In some cases, such as with Ubuntu LTS 18.04, X2Go provides better performance. If you use RDP and notice latency when interacting with the graphical desktop environment, consider trying X2Go since it may improve performance.

Important

Some marketplace images already have a graphical desktop environment and remote desktop server installed. For example, the Data Science Virtual Machine for Linux (Ubuntu) already has XFCE and X2Go Server installed and configured to accept client connections.

Enable remote desktop connection for RDP

This step is only needed to connect using RDP. If instead you plan to use X2Go, you can skip to the next section since X2Go uses the SSH port.

  1. During lab creation, the instructor has the option to Enable Remote Desktop Connection. The instructor must enable this option to open the port on the Linux VM that is needed for an RDP remote desktop session. Otherwise, if this option is left disabled, only the port for SSH is opened.

  2. On the Enabling Remote Desktop Connection message box, select Continue with Remote Desktop.

Install RDP or X2Go

After the lab is created, the instructor needs to ensure that a graphical desktop environment and remote desktop server are installed on the template VM. Instructors must first connect to the template VM using SSH to install the packages for:

  • Either the RDP or X2Go remote desktop server.
  • A graphical desktop environment, such as MATE, XFCE, etc.

After this is set up, the instructor can connect to the template VM using either the Microsoft Remote Desktop (RDP) client or X2Go client.

Follow the below steps to set up the template VM:

  1. If you see Customize template on the toolbar, select it. Then, select Continue on the Customize template dialog box. This action starts the template VM.

  2. After the template VM is started, you can select Connect template and then Connect via SSH on the toolbar.

  3. You see the following Connect to your virtual machine dialog box. Select the Copy button next to the text box to copy it to the clipboard. Save the SSH connection information. Use this connection information from an SSH terminal (like Putty) to connect to the virtual machine.

  4. Install either RDP or X2Go along with the graphical desktop environment of your choice. Refer to the following instructions:

Connect to the template VM via the GUI

After the template VM is set up, the instructor can connect via the GUI using either the Microsoft Remote Desktop (RDP) client or X2Go client. The client that you use depends on if RDP or X2Go is configured as the remote desktop server on the template VM.

Microsoft Remote Desktop (RDP) client

The Microsoft Remote Desktop (RDP) client is used to connect to a template VM that has RDP configured. The Remote Desktop client can be used on Windows, Chromebooks, Macs and more. Refer to the article on Remote Desktop clients for further details.

Follow the below steps based on the type of computer used to connect to the template VM:

  • Windows

    1. Click Connect to template on your lab's toolbar and select Connect via RDP to connect to the template VM.
    2. Save the RDP file and use it to connect to the template VM using the Remote Desktop client.
    3. Typically, the Remote Desktop client is already installed and configured on Windows. As a result, all you need to do is click on the RDP file to open it and start the remote session.

  • Mac

    1. Click Connect to template on your lab's toolbar and then select Connect via RDP to save the RDP file.
    2. Then, refer to the how-to article Connect to a VM using RDP on a Mac.

  • Chromebook

    1. Click Connect to template on your lab's toolbar and then select Connect via RDP to save the RDP file.
    2. Then, refer to the how-to article Connect to a VM using RDP on a Chromebook.

X2Go client

The X2Go client is used to connect to a template VM that has X2Go configured. Using the template VM's SSH connection information, follow the steps in the how-to article Connect to a VM using X2Go.

Next steps

After an instructor sets up either RDP or X2Go on their template VM and publishes, students can connect to their VMs via the GUI remote desktop or SSH.

For more information, see:

How secure is Windows Remote Desktop?

Remote Desktop sessions operate over an encrypted channel, preventing anyone from viewing your session by listening on the network. However, there is a vulnerability in the method used to encrypt sessions in earlier versions of RDP. This vulnerability can allow unauthorized access to your session using a man-in-the-middle attack.

Remote Desktop can be secured using SSL/TLS in Windows Vista, Windows 7, Windows 8, Windows 10 and Windows Server 2003/2008/2012/2016. *Some systems listed are no longer supported by Microsoft and therefore do not meet Campus security standards. If unsupported systems are still in use, a security exception is required.

While Remote Desktop is more secure than remote administration tools such as VNC that do not encrypt the entire session, any time Administrator access to a system is granted remotely there are risks. The following tips will help to secure Remote Desktop access to both desktops and servers that you support.

Basic Security Tips for Remote Desktop

1. Use strong passwords

Strong passwords on any accounts with access to Remote Desktop should be considered a required step before enabling Remote Desktop. Refer to the campus password complexity guidelines for tips.

2. Use Two-factor authentication

Departments should consider using a two-factor authentication approach. This topic is beyond the scope of this article, but RD Gateways can be configured to integrate with the Campus instance of DUO. Other unsupported by campus options available would be a simple mechanism for controlling authentication via two-factor certificate based smartcards. This approach utilizes the Remote Desktop host itself, in conjunction with YubiKey and RSA as examples.

3. Update your software

One advantage of using Remote Desktop rather than 3rd party remote admin tools is that components are updated automatically with the latest security fixes in the standard Microsoft patch cycle. Make sure you are running the latest versions of both the client and server software by enabling and auditing automatic Microsoft Updates. If you are using Remote Desktop clients on other platforms, make sure they are still supported and that you have the latest versions. Older versions may not support high encryption and may have other security flaws.

4. Restrict access using firewalls

Linux

Use firewalls (both software and hardware where available) to restrict access to remote desktop listening ports (default is TCP 3389). Using an RDP Gateway is highly recommended for restricting RDP access to desktops and servers (see discussion below). As an alternative to support off-campus connectivity, you can use the campus VPN software to get a campus IP address and add the campus VPN network address pool to your RDP firewall exception rule. Visit our page for more information on the campus VPN service.

5. Enable Network Level Authentication

Windows 10, Windows Server 2012 R2/2016/2019 also provide Network Level Authentication (NLA) by default. It is best to leave this in place, as NLA provides an extra level of authentication before a connection is established. You should only configure Remote Desktop servers to allow connections without NLA if you use Remote Desktop clients on other platforms that don't support it.

  • NLA should be enabled by default onWindows 10, Windows Server 2012 R2/2016/2019.

  • To check you may look at Group Policy setting Require user authentication for remote connections by using Network Level Authentication found at ComputerPoliciesWindows ComponentsRemote Desktop ServicesRemote Desktop Session HostSecurity. This Group Policy setting must be enabled on the server running the Remote Desktop Session Host role.

6. Limit users who can log in using Remote Desktop

By default, all Administrators can log in to Remote Desktop. If you have multiple Administrator accounts on your computer, you should limit remote access only to those accounts that need it. If Remote Desktop is not used for system administration, remove all administrative access via RDP, and only allow user accounts requiring RDP service. For Departments that manage many machines remotely remove the local Administrator account from RDP access at and add a technical group instead.

  1. Click Start-->Programs-->Administrative Tools-->Local Security Policy

  2. Under Local Policies-->User Rights Assignment, go to 'Allow logon through Terminal Services.' Or “Allow logon through Remote Desktop Services”

  3. Remove the Administrators group and leave the Remote Desktop Users group.

  4. Use the System control panel to add users to the Remote Desktop Users group.

A typical MS operating system will have the following setting by default as seen in the Local Security Policy:

The problem is that “Administrators” is here by default, and your “Local Admin” account is in administrators. Although a password convention to avoid identical local admin passwords on the local machine and tightly controlling access to these passwords or conventions is recommended, using a local admin account to work on a machine remotely does not properly log and identify the user using the system. It is best to override the local security policy with a Group Policy Setting.

To control access to the systems, even more, using “Restricted Groups” via Group Policy is also helpful.

If you use a “Restricted Group” setting to place your group, e.g., “CAMPUSLAW-TECHIES” into “Administrators” and “Remote Desktop Users,” your techies will still have administrative access remotely, but using the steps above, you have removed the problematic “local administrator account” having RDP access. Going forward, whenever new machines are added in the OU under the GPO, your settings will be correct.

7. Set an account lockout policy

By setting your computer to lock an account for a set number of incorrect guesses, you will help prevent hackers from using automated password guessing tools from gaining access to your system (this is known as a 'brute-force' attack). To set an account lockout policy:

  1. Go to Start-->Programs--> Administrative Tools--> Local Security Policy
  2. Under Account Policies--> Account Lockout Policies, set values for all three options. Three invalid attempts with 3-minute lockout durations are reasonable choices.

Best Practices for Additional Security

1. Do not allow direct RDP access to clients or servers from off campus.

Having RDP (port 3389) open to off campus networks is highly discouraged and is a known vector for many attacks. The options below list ways of improving security while still allowing RDP access to system.

Once an RDP gateway has been set up, hosts should be configured to only allow RDP connections from the Gateway host or campus subnets where needed.

2. Use RDP Gateways (Best Option)

Using an RDP Gateway is strongly recommended. It provides a way to tightly restrict access to Remote Desktop ports while supporting remote connections through a single 'Gateway' server. When using an RD Gateway server, all Remote Desktop services on your desktop and workstations should be restricted to only allow access only from the RD Gateway. The RD Gateway server listens for Remote Desktop requests over HTTPS (port 443) and connects the client to the Remote Desktop service on the target machine.

Microsoft remote desktop linux client

  1. Utilize Campus RDP Gateway Service. This is the best option to allow RDP access to system categorized as UC P2 and lower. Includes DUO integration. RDP Gateway Service is provided by the Windows Team. Documentation is available here: https://berkeley.sharepoint.com/sites/calnetad/gateway.

    The RDP Gateway Service also supports the new Remote Access Services requirement of the draft MSSND update (requirement 8), which requires the use of an approved service (i.e., RDP gateway, dedicated gateway, or bSecure VPN) for access to the UC Berkeley network from the public Internet.

  2. Dedicated Gateway Service (Managed). Needed for rdp access to systems that are UC P4 or higher. Must also be configured for DUO
    Some campus units use an IST managed VPS as an RD Gateway. A rough estimate might be that 30-100 concurrent users can use one RD Gateway. The HA at the virtual layer provides enough fault-tolerant and reliable access; however a slightly more sophisticated RD gateway implementation can be done with network load balancing.

  3. Dedicated Gateway Service (Unmanaged). Installing and configuring RD Gateway on department run hardware.
    There are many online documents for configuring this embedded Windows 2016/2019 component. The official documentation is here: https://docs.microsoft.com/en-us/windows-server/remote/remote-desktop-se...
    Installing the configuring, the role service is mostly as described; however, using a Calnet issued trusted Comodo certificate is recommended. Using a self-signed cert is ok for testing, and using a CalnetPKI cert can work if all clients have trusted the UCB root. The Comodo cert is usually better accepted so that your end users do not receive certificate warnings.
    Configuring your client to use your RD Gateway is simple.The official documentation for the MS Client is here: http://technet.microsoft.com/en-us/library/cc770601.aspx

In essence, a simple change on the advanced tab of your RDP client is all that is necessary:


3. Change the listening port for Remote Desktop

Changing the listening port will help to 'hide' Remote Desktop from hackers who are scanning the network for computers listening on the default Remote Desktop port (TCP 3389). This offers effective protection against the latest RDP worms such, as Morto. To do this, edit the following registry key (WARNING: do not try this unless you are familiar with the Windows Registry and TCP/IP): HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlTerminal ServerWinStationsRDP-Tcp. Change the listening port from 3389 to something else and remember to update any firewall rules with the new port. Although this approach is helpful, it is security by obscurity, which is not the most reliable security approach. You should ensure that you are also using other methods to tighten down access as described in this article.

4. Tunnel Remote Desktop connections through IPSec or SSH

Microsoft Remote Desktop On Linux Version

If using an RD Gateway is not feasible, you can add an extra layer of authentication and encryption by tunneling your Remote Desktop sessions through IPSec or SSH. IPSec is built-in to all Windows operating systems since Windows 2000, but use and management are greatly improved in Windows 10 (see: http://technet.microsoft.com/en-us/network/bb531150). If an SSH server is available, you can use SSH tunneling for Remote Desktop connections.

5. Use existing management tools for RDP logging and configuration

Using other components like VNC or PCAnywhere is not recommended because they may not log in a fashion that is auditable or protected. With RDP, logins are audited to the local security log, and often to the domain controller auditing system. When monitoring local security logs, look for anomalies in RDP sessions such as login attempts from the local Administrator account. RDP also has the benefit of a central management approach via GPO as described above. Whenever possible, use GPOs or other Windows configuration management tools to ensure a consistent and secure RDP configuration across all your servers and desktops.

By enforcing the use of an RDP gateway, you also get a third level of auditing that is easier to read than combing through the domain controller logins and is separate from the target machine so it is not subject to tampering. This type of log can make it much easier to monitor how and when RDP is being used across all the devices in your environment.

Microsoft Remote Desktop Linux Server


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