Red Hat® and Fedora® | ThinLinc by Cendio

The following information relates to installation of ThinLinc on an Red Hat Enterprise Linux or Fedora platform. The latest recommended version of this platform for use with ThinLinc can be found in the ThinLinc Administrator's guide, under "Server Requirements" .

Installation program hangs on Wayland

When trying to install the ThinLinc Server on systems running Wayland (rather than X11), the installation program will hang. To avoid this, launch the installation in text mode from a terminal.

$ DISPLAY= ./install-server

No automatic dependencies with DNF

The package tool Yum is being replaced with DNF, and ThinLinc does not yet support DNF for automatic installation of the necessary dependencies. They can be installed manually by running the following command before installing ThinLinc:

$ sudo dnf install lsb xorg-x11-xauth python-ldap \
  pygtk2 pygtk2-libglade selinux-policy-devel

Failure to start desktop or applications (missing OpenGL/GLX)

Modern Fedora includes a version of Mesa that disrupts OpenGL in remote desktop systems such as ThinLinc ([1]). This causes desktop environments such as GNOME, KDE and Cinnamon to crash. Make sure Mesa 12 or older is installed to ensure proper function of ThinLinc.

$ sudo dnf downgrade --allowerasing mesa-* 

If you don't want to downgrade, you will be able to run desktop environments like LXDE, XFCE or Mate that doesn't require OpenGL.

Note that a bug in the package libepoxy causes segmentation faults in cases when no OpenGL is found. Many applications, for example all GTK3 applications, attempt to initiate OpenGL regardless of whether they need it or not. This means that such applications fail to start, even if you run a desktop environment that otherwise works. This bug was fixed in libepoxy version 1.4.

Polkit authentication dialogs during login

Recent versions of both GNOME 3 and KDE contains bugs ([1],[2],[3]) which causes Polkit authentication dialogs to appear during login, when resizing the session etc. It is possible to prevent such dialogs by creating the file /etc/polkit-1/rules.d/40-thinlinc-no-auth-dialogs.rules with this content:

polkit.addRule(function(action, subject) {
   if (action.id == "org.freedesktop.color-manager.create-device" ||
        action.id == "org.freedesktop.color-manager.create-profile" ||
        action.id == "org.freedesktop.color-manager.delete-device" ||
        action.id == "org.freedesktop.color-manager.delete-profile" ||
        action.id == "org.freedesktop.color-manager.modify-device" ||
        action.id == "org.freedesktop.color-manager.modify-profile") {
	if (!subject.local) {
		return polkit.Result.NO;
	}
   }
});

polkit.addRule(function(action, subject) {
   if (action.id == "org.freedesktop.packagekit.system-network-proxy-configure" ||
       action.id == "org.freedesktop.packagekit.system-sources-refresh") {
	if (!subject.local) {
		return polkit.Result.NO;
	}
   }
});

Please note that the file should be created in /etc/polkit-1/rules.d. Otherwise it may be necessary to restore the SELinux context by running restoreconf on the file. For more information, see Bug 5584.

SELinux

See section SELinux for information about configuring SELinux on this platform.