7. XDMCP, VNC y Thin Clients


7.1 Habilitando el acceso por XDMCP

Habilitando XDMCP en KDE (ubuntu)

Let go ahead and make the changes to /etc/kde3/kdm/kdmrc first:

sudo vi /etc/kde3/kdm/kdmrc

Scroll down until you find a section starting with [Xdmcp], a few lines below you'll find a line as follows:


Get rid of the '#' and make sure it says Enable=true

Also get rid of the '#' in front of the following lines:





Go ahead and save the file.


Now we're going to make the changes to the Xaccess file:

sudo vi /etc/kde3/kdm/Xaccess

Only two changes to make to this file:

Get rid of the '#' at the beginning of the following line (and only the '#' at the beginning of the line, leave the second one there):

#*               #any host can get a login window

Same thing for this line too:

#*           CHOOSER BROADCAST  #any indirect host can get a chooser

Save the file.


Now we need to restart the KDM process so it will re-read the configuration file. The easiest way to do this is to just reboot the machine. The quickest is to do the following:

ps -ef | grep kdm

This will print out a list of processes with the letters 'kdm' in the name. Find the one that looks like the following (Specifically the one that ends in /usr/bin/kdm):

root    4530      1     0 0:09:20 ?          00:00:00 /usr/bin/kdm

See the number right after root? 4530 in my example, you will almost certainly have a different number. That's the process ID or PID. Type the following command to restart kdm (Substituting the PID number you have for the 4530 in my example):

sudo kill -HUP 4530

Habilitando XDMCP en Gnome (ubuntu)


  1. System > Administration > Login Screen Setup Menu
  2. Enter your administration password Enter Password
  3. Under the Security tab, Enable XDMCP
  4. You can then Close the window



edit /etc/X11/gdm/gdm.conf

Search for the section [XDMCP]
Change the line “Enable=false” to “Enable=true”

Restart X


Para otros sistemas/versiones



7.2 Clientes de XDMCP


7.3 VNC


7.4 Software para Thin Clients