Xmanager 7 XDMCP Configurations (gdm Based)

Unlike previous versions, Xmanager 7 supports the Gnome3 and Gnome40 based user environments.

OSes that support the Gnome 3 User Environment:

  • Ubuntu 12.10 or higher
  • CentOS 7.0 or higher
  • Redhat Enterprise Linux 7.0 or higher
  • Fedora 18 or higher
  • Other Linux OS packaged after 2013

OSes that support the Gnome 40 User Environment

  • Fedora 34 (currently in beta on 04/06/2021)


Xmanager 6 (and lower versions) as well as Xmanager 7 Classic do not support the Gnome3 user environment, so switching to the Xfce or KDE user environment were required. Xmanager 7 utilizes a new X server and does not require switching user environments and can use the default Gnome user environment.

However, you cannot create multiple sessions with the same user when using gdm or gdm3. After logging in, the desktop screen will not display properly or the session will terminate.

Therefore, even if you are using Xmanager 7's X server, you may run into issues. Please see the chart below for how certain XDMCP Daemon and User Desktop Environment combinations will perform.

Xmanager Type
XDMCP Daemon
User Desktop Environment
Supports Multi Session (Y/N)
Recommended (Y/N)
Xmanager 7, Xmanager 7 ClassiclightdmXfce , KDE, cinnamon...YY
Xmanager 7lightdmGnomeY (requires additional lightdm configurations)Y
Xmanager 7gdm, gdm3GnomeNN

For lightDM and Xfce installation and configuration instructions, refer to the XDMCP configuration section of your relevant OS in Remote Host Configuration.


gdm3 Configuration Instructions

  1. Configure XDMCP
    To configure the gdm3 environment, you need to edit the /etc/gdm/custom.conf or /etc/gdm3/custom.conf file and set Enable to 1 (or true) under the [xdmcp] section. If this file does not exist, create a file with the following contents.
    (/etc/gdm3/daemon.conf for Debian 10.9)

    [daemon]
    ...
    WaylandEnable=false
    ...
    
    [xdmcp]
    Enable=true
    MaxSessions=99
    DisplaysPerHost=99

    NOTE: With the gdm3 XDMCP daemon, you cannot create multiple different sessions with the same username. If you want to work with multiple different sessions with the same username , you should use another daemon such as lightdm instead of the default gdm3 daemon . For lightdm installation instructions, refer to the OS package installer or the XDMCP configuration section of your the OS in the UNIX/Linux OS configuration section of this FAQ.

  2. Reboot the Linux device or run the following command:

    # systemctl restart gdm OR systemctl restart gdm3
  3. After configuring the firewall, run Xmanager.
    If the iptable firewall is running on the system, you need to stop the iptable with the following command:

    # systemctl stop firewalld


    Or you can open up the ports below:

    • Open UDP port 177 from the PC to UNIX/Linux
    • Open TCP port 6000~6010 from UNIX/Linux to the PC