Hi,

recently I've updated from FC24 to FC27. Since then remote X connections don't work anymore. For my environment I'm typically starting an xterm shell from another computer displaying on my workstation.

When using "gdm", remote X access is en-/disabled with the "DisallowTCP" setting in "/etc/gdm/custom.conf".

Now, there is a trap door. Xorg changed the default for remote connections a few releases ago. Old releases listened on the network unless "-nolisten tcp" was specified. Newer releases only listen on the network if "-listen tcp" is specified on the command line to start the X server.

This means that gdm either needs to add "-nolisten tcp" (old server, DisallowTCP=true) or "-listen tcp" (new server, DisallowTCP=false) to the X server command line.

This is handled by conditional compilation in gdm (depending on a HAVE_XSERVER_THAT_DEFAULTS_TO_LOCAL_ONLY define).

The setting for this define is determined in configure.ac, lines

dnl --------------------------------------------------------------------------- dnl - Check if Xorg is new enough to require '-listen tcp' (1.17) dnl ---------------------------------------------------------------------------

if $PKG_CONFIG --atleast-version=1.17 xorg-server; then    AC_DEFINE([HAVE_XSERVER_THAT_DEFAULTS_TO_LOCAL_ONLY], [], [XServer disables tcp access by default]) fi

Now, my installed gdm seems to think that my Xserver doesn't default to "local only". If I set DisallowTCP to true, it adds a "-nolisten tcp" parameter to the X command line. While it shouldn't add anything in this case. If I set DisallowTCP to false it doesn't add anything to the command line (where it should add "-listen tcp").

On my system, running the test above returns correct results:

$ pkg-config --atleast-version=1.17 xorg-server ; echo $? 0 $

I've build the gdm RPM from source on my local machine, installed it, and, hey, now everything works as expected.

So I guess that the machine used to build the official packages still has an old X server installed. If that's true, could this be fixed?

regards, chris