I want to tunnel via ssh a Xdmcp protocol. To access sicure to a remote login. An easy solution can be openvpn, but I want to try socat+ssh first. The server is Solaris 10 The client is Slackware 15. On Client ssh -L 6667:localhost:6667 192.168.201.200 on server socat tcp4-listen:6667,reuseaddr,fork UDP:192.168.201.200:177 on Client sudo socat udp4-listen:177,reuseaddr,fork tcp:localhost:6667 Now on client i run Xephyr and... Xephyr -query localhost -screen 1024x767 :2 Using Xdcmp directly without tunnel works, but is unsafe

I want to be able to connect remotely to my daily driver (Debian 11) within my LAN from my laptop and other devices. Ssh works fine but niether Chrome nor Firefox are happy running over ssh / some tasks are easier done from a GUI environment. The laptop runs MS-Windows 10 and I usually use Mobaxterm to connect. Specifically, I want the computer to continue functioning as a workstation running X with graphical login while also providing multi-user GUI sessions over the network. My choices therefore appeared to be: XDMCP, VNC or RDP. I have in the past provisioned all 3 successfully - but none recently. I expected this to be straightforward. As a precursor to running the following, I installed lightdm in pace of sddm and ensured that there were no iptables rules in place. Login via the console is still functioning, but I have failed to get XDMCP or VNC working. I've not tried with RDP as my previous experience was that this was not as robust as the other mechanisms. 1) Trying XDMCP: Amended /etc/lightdm.conf , added: [XDMCPServer] enabled=true Rebooted. netstat -nap showed lightdm listening on UDP 0.0.0.0:177. When I attempted to connect from a MS-Windows machine running Mobaxterm, a window opened and closed immediately. lightdm.log shows:

[+344.80s] DEBUG: Got Query(authentication_names=[]) from 192.168.0.87:57445
[+344.80s] DEBUG: Send Willing(authentication_name='' hostname='animal' status='') to 192.168.0.87:57445
[+345.04s] DEBUG: Got Request(display_number=1 connections=[] authentication_name='' authentication_data= authorization_names=['MIT-MAGIC-COOKIE-1' 'XDM-AUTHORIZATION-1'] manufacturer_display_id='') from 192.168.0.87:57445
[+345.04s] DEBUG: Send Decline(status='No valid address found' authentication_name='' authentication_data=) to 192.168.0.87:57445

Google found 6 hits when I searched for the error message in the last log entry there - they didn't help me. 2) Trying VNC. I backed out the changes above, added:

[VNCServer]
	enabled=true
	command=Xvnc
	port=5900
	listen-address=0.0.0.0
	width=1024
	height=768
	depth=8

Rebooted. Again netstat -nap showed lightdm listening on TCP 0.0.0.0:5900. On trying to connect using Mobaterm, the client prompted me for a password which I left blank and got "Connection closed". This repeated a second time. Log entries shown below.

[+50.20s] DEBUG: Got VNC connection from 192.168.0.87:52259
[+50.20s] DEBUG: Seat vnc0: Loading properties from config section Seat:*
[+50.20s] DEBUG: Seat vnc0: Starting
[+50.20s] DEBUG: Seat vnc0: Creating greeter session
[+50.20s] DEBUG: Seat vnc0: Creating display server of type x
[+50.20s] DEBUG: XServer 1: Logging to /var/log/lightdm/x-1.log
[+50.20s] DEBUG: XServer 1: Writing X server authority to /var/run/lightdm/root/:1
[+50.20s] DEBUG: XServer 1: Launching X Server
[+50.20s] DEBUG: Launching process 1430: /usr/bin/Xvnc -rfbauth /etc/vncpasswd :1 -auth /var/run/lightdm/root/:1 -nolisten tcp -inetd -geometry 1024x768 -depth 8
[+50.20s] DEBUG: XServer 1: Waiting for ready signal from X server :1
[+50.20s] DEBUG: Registering seat with bus path /org/freedesktop/DisplayManager/Seat1
[+50.23s] DEBUG: Process 1430 exited with return value 1
[+50.23s] DEBUG: XServer 1: X server stopped
[+50.23s] DEBUG: XServer 1: Removing X server authority /var/run/lightdm/root/:1
[+50.23s] DEBUG: Seat vnc0: Display server stopped
[+50.23s] DEBUG: Seat vnc0: Stopping session
[+50.23s] DEBUG: Seat vnc0: Session stopped
[+50.23s] DEBUG: Seat vnc0: Stopping display server, no sessions require it
[+50.23s] DEBUG: Seat vnc0: Stopping; greeter display server failed to start
[+50.23s] DEBUG: Seat vnc0: Stopping
[+50.23s] DEBUG: Seat vnc0: Stopped
[+57.93s] DEBUG: Got VNC connection from 192.168.0.87:52260
[+57.93s] DEBUG: Seat vnc1: Loading properties from config section Seat:*
[+57.93s] DEBUG: Seat vnc1: Starting
[+57.93s] DEBUG: Seat vnc1: Creating greeter session
[+57.93s] DEBUG: Seat vnc1: Creating display server of type x
[+57.93s] DEBUG: XServer 1: Logging to /var/log/lightdm/x-1.log
[+57.93s] DEBUG: XServer 1: Writing X server authority to /var/run/lightdm/root/:1
[+57.93s] DEBUG: XServer 1: Launching X Server
[+57.93s] DEBUG: Launching process 1431: /usr/bin/Xvnc -rfbauth /etc/vncpasswd :1 -auth /var/run/lightdm/root/:1 -nolisten tcp -inetd -geometry 1024x768 -depth 8
[+57.93s] DEBUG: XServer 1: Waiting for ready signal from X server :1
[+57.93s] DEBUG: Registering seat with bus path /org/freedesktop/DisplayManager/Seat2
[+57.94s] DEBUG: Process 1431 exited with return value 1
[+57.94s] DEBUG: XServer 1: X server stopped
[+57.94s] DEBUG: XServer 1: Removing X server authority /var/run/lightdm/root/:1
[+57.94s] DEBUG: Seat vnc1: Display server stopped
[+57.94s] DEBUG: Seat vnc1: Stopping session
[+57.94s] DEBUG: Seat vnc1: Session stopped
[+57.94s] DEBUG: Seat vnc1: Stopping display server, no sessions require it
[+57.94s] DEBUG: Seat vnc1: Stopping; greeter display server failed to start
[+57.94s] DEBUG: Seat vnc1: Stopping
[+57.94s] DEBUG: Seat vnc1: Stopped

I also tried with 'command=Xvnc -SecurityTypes None' and with 'command=Xvnc -rfbauth /etc/vncpasswd' after setting a VNC password. Logs were similar to above. I also tried the first configuration using an Android tablet withe RealVNC viewer. This did not prompt for a password, but reported "connection closed" immediately.

Is there any way to start a **XDMCP** session, say with **Xephyr** in **LightDM**, locally through **Unix Sockets** instead of **IP**? For performance I was wondering if, somehow, I can avoid any network stack working with **Xephyr** and the **XDMCP** server in the same machine.

I have a Digital Unix 4.0 emulation running without a display (FreeAXP). I have an X app (Open Genera 2) on this host that I would like to use. I managed to configure both Unix and Linux and I can do X login from Linux (Debian 11 at the moment) to Unix. Both X and CDE environments seem to be working fine. However, when I run the mentioned application, I only see a (white) blank window without any contents. I tried a different X server (on Windows) and also not using XDM but setting display explicitly and running the program from telnet, but no change. I can see the network traffic (on 6000/tcp) with tcpdump on Unix. I am considering using Xvfb on Unix to see if it works locally and also proxy/debug X messages on Linux, but I dont see why it would be different. What am I missing ?

I know XDMCP cannot be forwarded over SSH because XDMCP uses UDP and SSH uses TCP. Can XDMCP be forwarded over SSL or TLS instead? XDMCP is not encrypted by default. Can AES or RSA be added to XDMCP connection?

My environment consist of a Ubuntu 14.04 LTS VM. This is acting as the Xnest server on socket :2 and port 6002 (as seen by netstat). I'm running the Xnest as client on a Fedora 20 VM. The Ubuntu system runs Xnest 2:1:15:1. My Xnest version on Fedora is 1.14.4-14.fc20. When I try to remote connect from Fedora I can seem to connect but I get a black screen and not sure what I am doing wrong, if anything. I start the server on Ubuntu by running: Xnest :2 From Fedora (the Client) I run: Xnest -ac -query 192.168.17.105 :2 -geometry 1024x768 And here is what I see in Fedora: Any ideas as to what I may be doing wrong, or if this is possibly a bug?

While digging into X Windows or X11 stuff I found that X display uses MIT-MAGIC-COOKIE to allow client-server to exchange display data. One thing I don't understand is that I am able to locate and view the MIT-MAGIC-COOKIE in the server(Xclient) with the command xauth list and I see stuff like James5/unix:10 MIT-MAGIC-COOKIE-1 1bcafdd569b2e1e6dd0dfaf446f437a6 James5/unix:13 MIT-MAGIC-COOKIE-1 5e536e4c17c94372ebc932f6d1c43abc James5/unix:15 MIT-MAGIC-COOKIE-1 999ac8b086f2f8091aa970f40b739ff4 James5/unix:11 MIT-MAGIC-COOKIE-1 89287e67dfc851c5e7188fc5b7e4dc31 but from what I've learned, the user side should also have this cookie as well in order to compare the cookie from the received X display data. but when I come back to my 'user side' laptop and type Black@Black-PC ~ $ xauth list an error message like this appears... xauth: file /home/Black/.Xauthority does not exist Where on earth can I locate the .Xauthority file on the user side?

In RHEL5, I can press F10 to choose "remote login via xdmcp" at the login window, how to do the same thing in RHEL6/7?

The network structure is: Server -> NAT router1 -> switch <- NAT router2 <- Client The part I cannot solve is that, after xserver connects to 177/udp of xdm, xdm connects back to xserver, say 6001/tcp. So the server network does not know how to connect to the IP inside another NAT. The NAT routers are not rich functioned (as to routing), just exposes any ports necessary. For example, I exposed 22/tcp and 177/udp from Server. I tried xqproxy, xdm just rejects the session id.

Providing XDMCP service itself is not hard. Some configuration with XDM is enough. But XDM has to start a X process and show something, if there is some hardware issues, it tails to start. While in my opinion, XDMCP server is pure CPU task. So, is it possible to provide XDMCP service without using video card or screen? Just like running Nginx in background? When I tried it in my case, the X process started by XDM died due to "no screens found". I do not want to pay attention on fixing that since local monitor means nothing to me. I followed https://wiki.archlinux.org/index.php/XDMCP to do the modification. And xdm.log says:

xdm info (pid 1048): Starting xdm 1.1.12
xdm error (pid 1048): error binding socket address 177: Cannot assign requested address
xdm info (pid 1048): Starting X server on :0

X.Org X Server 1.20.5
X Protocol Version 11, Revision 0
Build Operating System: Linux Arch Linux
Current Operating System: Linux 9b8258ba662e 4.14.122-rancher #1 SMP Tue May 28 01:50:21 UTC 2019 x86_64
Kernel command line: BOOT_IMAGE=../vmlinuz-4.14.122-rancher printk.devkmsg=on rancher.state.dev=LABEL=RANCHER_STATE rancher.state.wait panic=10 console=tty0  initrd=../initrd-v1.5.2
Build Date: 30 May 2019  06:44:40PM
 
Current version of pixman: 0.38.4
	Before reporting problems, check http://wiki.x.org 
	to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.0.log", Time: Wed Jun  5 07:05:01 2019
(==) Using system config directory "/usr/share/X11/xorg.conf.d"
(EE) 
Fatal server error:
(EE) no screens found(EE) 
(EE) 
Please consult the The X.Org Foundation support 
	 at http://wiki.x.org 
 for help. 
(EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
(EE) 
(EE) Server terminated with error (1). Closing log file.
xdm error (pid 1048): server unexpectedly died
xdm error (pid 1048): Server for display :0 can't be started, session disabled

When using CDE on older Solaris systems (2.5.x) remotely using XDMCP with TrueColor visuals, on-screen pixmaps are missing the blue channel and have the red and green channels swapped. This means that white appears as yellow, green as red, red as green, blue as black, etc. Is there some X server setting I can use to override this or work around it, or alternate X server that is compatible with whatever the Solaris apps are doing? This does not affect all on-screen elements; window borders, text-labelled widgets like menus and buttons are coloured according to the default CDE colour scheme and have their normal colours. Icons and other visual elements that are xpm images, such as the background pattern and elements of the CDE front panel, have incorrect colours as noted. In addition, when I open an xpm in the icon editor (dticon) both the multicolour preview and the magnified pixel area have incorrect colours, however the 2-colour preview and the colour palette have correct colours. I have the same problem whether the XDMCP client is Cygwin/X or Xming in Windows or Xorg in Debian. If I use Xorg in Debian with -depth 8 (which I guess selects PseudoColor visuals instead of TrueColour) colour channels are not swapped and colours appear as one would expect in 256-colour mode, however I'd rather have 24-bit colour support and avoid the added inconvenience of having to run X through virtualization or switch Windows to 256-colour mode.

I am trying to set up remote desktop into a Debian stretch distribution, I set up the file /etc/gdm3/daemon.conf. [daemon] WaylandEnable = false [security] DisallowTCP = false [xdmcp] Enable = true Port = 177 [chooser] [debug] # Uncomment the line below to turn on debugging # More verbose logs # Additionally lets the X server dump core if it crashes Enable = true But when I restart the debian system, I see the following output on netstat: udp6 0 0 :::177 :::* 11059/gdm3 That is using udp6 and not udp4. I have tried disabling inet6 into the system with the following lines into /etc/sysctl.conf: net.ipv6.conf.all.disable_ipv6 = 1 net.ipv6.conf.default.disable_ipv6 = 1 net.ipv6.conf.lo.disable_ipv6 = 1 I refresh the settings with sysctl -p, and restart the services with sudo init 3; sudo unit 5, but nothing change. I have rebooted the VM even, and still the same. Any idea how I can force xdcmp to be listening on UDP v4 and not udp6?? Thanks in advance. I am doing this to figure out the settings needed into another machine with the same linux distribution where I want to set up remote access to the desktop (so, I am gonna get the same issue). Actually I can access with xvnc running into the other host, but I want to set up xdmcp to request the login on remote access. The exact system I am running: $ lsb_release -a No LSB modules are available. Distributor ID: Debian Description: Debian GNU/Linux 9.4 (stretch) Release: 9.4 Codename: stretch $ apt-cache show gdm3 Package: gdm3 Version: 3.22.3-3+deb9u1 . . .

I'm trying to set up a remote desktop connection to access my desktop PC from my laptop (both running Trisquel) over wifi. I've tried VNC and it was terribly slow, so I'm looking at alternative options. What I would ideally like to do is to start a remote X session over SSH, which would run on a separate tty on my laptop (i.e. tty8), using X forwarding. It seems like it should be possible, but I'm trying to get my head around how it works. The X forwarding over the SSH tunnel seems to work fine for individual X applications, using ssh -X. I can also start a new local X session on tty8 by using the following command (with xinit installed): startx lxsession -- :1 tty8 So, putting two and two together, I should be able to start a remote session over the SSH connection by typing the following command after logging in to the remote machine with SSH, right?: startx gnome-session -- :1 tty8 But no, it doesn't work! I get the following error: X: user not authorized to run the X server, aborting. From what I've read, it seems that I need to use either XDMCP and/or X nesting to accomplish this. So, my question is: why is it necessary to use these extra packages to do this? I thought that X is supposed to have network transparency, in which case, why would it know/care whether the tty I'm trying to use is on a local or a remote machine? What does XDMCP/X nesting bring in to the picture, that X doesn't include by default? I'm just trying to get my head around this and understand it a bit better.

I am trying to get xdmcp working on a Redhat 6 server. I am mostly following the steps at: http://www.yolinux.com/TUTORIALS/GDM_XDMCP.html#RHEL In one of the steps it suggests: Edit file: Red Hat: /etc/X11/xdm/Xaccess On my system, I do not see this file or the xdm folder. I only have /etc/X11: $ ls -l /etc/X11 total 32 drwxr-xr-x. 2 root root 4096 Jun 29 2011 applnk drwxr-xr-x. 2 root root 4096 Oct 2 2013 fontpath.d -rwxr-xr-x 1 root root 1328 Aug 26 2014 prefdm drwxr-xr-x 4 root root 4096 Oct 29 17:43 xinit -rw-r--r-- 1 root root 547 Jun 6 2013 Xmodmap -rw-r--r--. 1 root root 68 Oct 2 2013 xorg.conf drwxr-xr-x 2 root root 4096 Nov 3 2016 xorg.conf.d -rw-r--r-- 1 root root 493 Jun 6 2013 Xresources So far, I am getting a blank screen if I try to open an xdmcp session via mobaXTerm. I have already followed most of the steps in the tutorial I noted above including disabling my firewall. I also have gdm running: $ ps -eaf | grep gdm root 1818 1 0 20:07 ? 00:00:00 /usr/sbin/gdm-binary -nodaemon root 1848 1818 0 20:07 ? 00:00:00 /usr/libexec/gdm-simple-slave --display-id /org/gnome/DisplayManager/Display1 root 1851 1848 0 20:07 tty1 00:00:00 /usr/bin/Xorg :0 -br -verbose -audit 4 -auth /var/run/gdm/auth-for-gdm-h5txFF/database vt1 gdm 1937 1 0 20:07 ? 00:00:00 /usr/bin/dbus-launch --exit-with-session gdm 1938 1 0 20:07 ? 00:00:00 /bin/dbus-daemon --fork --print-pid 5 --print-address 7 --session gdm 1939 1848 0 20:07 ? 00:00:00 /usr/bin/gnome-session --autostart=/usr/share/gdm/autostart/LoginWindow/ gdm 1946 1 0 20:07 ? 00:00:00 /usr/libexec/gconfd-2 gdm 1964 1939 0 20:07 ? 00:00:00 /usr/libexec/at-spi-registryd gdm 1965 1 0 20:07 ? 00:00:05 /usr/libexec/gnome-settings-daemon --gconf-prefix=/apps/gdm/simple-greeter/settings-manager-plugins gdm 1967 1 0 20:07 ? 00:00:00 /usr/libexec/bonobo-activation-server --ac-activate --ior-output-fd=12 gdm 1974 1 0 20:07 ? 00:00:00 /usr/libexec/gvfsd gdm 1975 1939 0 20:07 ? 00:00:00 metacity gdm 1976 1939 0 20:07 ? 00:00:00 /usr/libexec/polkit-gnome-authentication-agent-1 gdm 1978 1939 0 20:07 ? 00:00:00 /usr/libexec/gdm-simple-greeter gdm 1991 1 0 20:07 ? 00:00:00 /usr/bin/pulseaudio --start --log-target=syslog root 1998 1848 0 20:07 ? 00:00:00 pam: gdm-password At this point though, I do wish to be sure I have done the necessary xdm config. But how is it done with Redhat 6?

When I try to export the remote display I do: In my Ubuntu 17.04:

xhost +
access control disabled, clients can connect from any host

Then I make the connection to the server:

ssh user@server

Once in the server get this error:

user@server:~$ export DISPLAY=my_ip:0.0
user@server:~$ xeyes
Error: Can't open display: my_ip:0.0

My gdm configuration is: **root@my_ip:/etc/gdm3# cat custom.conf**

# GDM configuration storage
#
# See /usr/share/gdm/gdm.schemas for a list of available options.

[daemon]
# Uncoment the line below to force the login screen to use Xorg
#WaylandEnable=false

# Enabling automatic login
#  AutomaticLoginEnable = true
#  AutomaticLogin = user1

# Enabling timed login
#  TimedLoginEnable = true
#  TimedLogin = user1
#  TimedLoginDelay = 10

[security]
DisallowTCP=false

[xdmcp]
Enable=true
DisplaysPerHost=10 

[chooser]

[debug]
# Uncomment the line below to turn on debugging
# More verbose logs
# Additionally lets the X server dump core if it crashes
#Enable=true

**GDM3 Version**

gdm3 --version
GDM 3.24.0

**netstat -puta**

Conexiones activas de Internet (servidores y establecidos)
Proto  Recib Enviad Dirección local         Dirección remota       Estado       PID/Program name    
tcp        0      0 0.0.0.0:x11-1           0.0.0.0:*               ESCUCHAR    1477/Xorg           

**ps fax | grep X**

 1211 tty1     Sl+    0:01  |       \_ /usr/lib/xorg/Xorg vt1 -displayfd 3 -auth /run/user/120/gdm/Xauthority -background none -noreset -keeptty -verbose 3
 1477 tty2     Sl+    0:35          \_ /usr/lib/xorg/Xorg vt2 -displayfd 3 -auth /run/user/1000/gdm/Xauthority -listen tcp -background none -noreset -keeptty -verbose 3

**tcpdump**

11:41:20.065425 IP server.41874 > my_ip.x11: Flags [S], seq 1478700027, win 29200, options [mss 1460,sackOK,TS val 22197350 ecr 0,nop,wscale 7], length 0
11:41:20.065447 IP my_ip.x11 > server.41874: Flags [R.], seq 0, ack 1478700028, win 0, length 0

I'm using XDMCP to access CentOS 6 hosts from Cygwin/X. Everything works fine, but every now and then attempting to connect results in the error message: XDMCP fatal error: Session declined maximum number of open sessions from your host reached However no session is active and I was wondering if there was a way to clear these phantom connections so as to be able to connect again without having to raise the number of sessions allowed. I'm aware that this problem can be solved by rebooting the system, but sometimes that is not an option.

How can I configure XDM server to accept remote X login and works as X server, which Configuration should be done on the clients if they want to connect to this X server?

this is my situation: there are three computers 1. lab server (CentOS) 2. lab personal computer(window s7) 3. personal laptop(ubuntu) since the lab server only allowed ip address of my desktop at the lab, I was unable to establish a direct remote connection to the lab server through my laptop. So I have reached to the point where I made my lap desktop into a ssh server where now I can eventually connect to the lab server through my laptop. But the problem is that I was only able to connect to the lab server only in the CLI basis. The real deal is that I want to use the simulation programs which involves X windows stuff. After a lot of struggling, with my laptop---lab desktop----lab server connected established, I execute the simulation program through my laptop but what really happens is the simulation program is executed and displayed at the 'lab desktop'.. in other words, I have failed to send the X windows display data from 'lab server' to 'my laptop'.. I guess this does make sense since eventually the regardless of how further I am logged in to the lab server, the connection coming 'out' from the lab server is tunneled to my 'lab desktop'. So I guess the X display data is automatically sent to my 'lab desktop'. So I am guessing that there could be two ways to solve this: 1. find a way that I don't know yet which will enable the X display data to be sent from the 'lab server' directly to 'my laptop'... 2. find a way to somehow 'port forward' my lab desktop so that the incoming X display data from the lab server toward 'my laptop'... Can anyone help me in anyway on this matter??

Connecting to a remote Solaris 10 system over X11 I observe inconsistent behavior regarding the used fonts. I am connecting from a Cygwin/X system. When I connect using ssh forwarding like this $ ssh -Y mymachine.example.org fonts work as expected, i.e. the rendering is very nice and programs seem to find all kind of different fonts (e.g. gvim or emacs). When I connect to the same machine via XDMCP (to the stock blue Solaris 10 login manager screen) and login there seems only 1 fixed size font available. An Emacs from OpenCSW even fails to execute because it can't find the fonts it needs. It prints that it can't find a font using following specification: -dt-interface user-medium-r-normal-m I establish the XDMCP connection like this: $ XWin -query mymachine.example.org -from mywindowsclient.example.org My objective is no to get also proper fonts for the XDMCP use case. How can I investigate this issue? Can I duplicate some configuration which is implicitly used with ssh -Y for the XDMCP case? How is the font-thing usually setup during ssh-X11-forwarding?

I have a RHEL6 server which we connect via XDMCP. If I start xdm (xdm &) it works but the login screen is the old xdm simple login and not gdm. Our RHEL5 servers connect to gdm just fine. The problem is that GDM isn't running. When I try to launch GDM (gdm &) it gives me the following message: ** (gdm-binary:3229): WARNING **: Couldn't connect to system bus: Failed to connect to socket /var/run/dbus/system_bus_socket: No such file or directory I've also tried using (gdm-binary &) and get the same message. cat /etc/gdm/custom.conf # GDM configuration storage [daemon] [security] DisallowTCP=false AllowRemoteRoot=true [xdmcp] Enable=true [greeter] IncludeAll=true [chooser] [debug] In /etc/X11/xdm/Xaccess I have the following uncommented: * #any host can get a login window In /etc/X11/xdm/xdm-config I have tried commenting and uncommenting the following: DisplayManager.requestPort: 0 I've referenced several tutorials such as: http://www.yolinux.com/TUTORIALS/GDM_XDMCP.html http://kosala-linux.blogspot.com/2013/02/x-manager-configurations-for-rheloel.html