Technical data

Configuring XDMCP-Compatible X Displays
19.1 Key Concepts
To reinitialize the X terminal, the XDM process had to be restarted. This problem
was solved through the development of the XDM Control Protocol.
Now, because of XDMCP, XDM can listen for management requests from X
terminals as well as use the XSERVERS file for the X terminals that were not
XDMCP compatible. Most X terminals today are XDMCP compatible.
The TCP/IP Services implementation of XDM is based on the X11R6.1 release
from X Consortium.
19.2 XDMCP Queries
XDMCP provides the following methods to query XDM for service:
• Direct
X terminals, configured for the direct request method, send a connection
request to a specific host.
• Broadcast
X terminals, configured for a broadcast request, send out a general query to
ask for service from all nodes running XDM. A list of the responding nodes is
then presented to the user for selection by the client software.
• Indirect
An indirect request is used to relay a request for service from one XDM node
to another.
The TCP/IP Services implementation of XDM does not support the indirect query
with a chooser box supported by some other XDM servers.
An authentication protocol is supported for all three types of requests.
19.3 XDM Configuration Files
If the files are present, XDM uses the following files to configure the X display
environment:
• Master configuration (XDM_CONFIG.CONF)
• Servers (XSERVERS.TXT)
• Access (XACCESS.TXT)
• Keys (XDM_KEYS.TXT)
• Session (XDM_XSESSION.COM)
After installing XDM, you can use the TCP/IP Services-supplied configuration
templates located in SYS$SPECIFIC:[TCPIP$XDM] to create the configuration
files. The default directory location of the configuration and template files is the
SYS$SPECIFIC:[TCPIP$XDM] directory.
19.3.1 Master Configuration File
The master configuration file, which is an optional file, specifies the location and
file names of the other configuration files used to control the operation of XDM.
Example 19–1 shows the contents of the default configuration template file
(XDM_CONFIG.TEMPLATE) supplied with XDM:
19–2 Configuring XDMCP-Compatible X Displays