Adding and Removing Displays and Terminals for AIX Common Desktop Environment

The login manager may be started from a system with a single local bitmap or graphics console. Many other situations are also possible, however (see figure). You may want to start AIX Common Desktop Environment from:

• Local consoles.
• Remote consoles.
• Bitmap and character-display.
• X Display Manager Control Protocol (XDMCP) Xstations.
• Non-XDMCP Xstations.
• Xterminal systems running on a host system on the network.

An Xterminal system consists of a display device, keyboard, and mouse that runs only the X server. Clients, including AIX Common Desktop Environment, are run on one or more host systems on the networks. Output from the clients is directed to the Xterminal display.

Wherever possible, you should use terminals that support XDMCP (X Display Manager Control Protocol).

The following Login Manager configuration tasks support many possible configurations.

• Adding an Xstation Terminal that supports XDMCP
• Adding a Non-XDMCP Xstation Terminal
• Removing a Local Display
• Adding an ASCII or Character-Display Terminal

Adding an Xstation Terminal that supports XDMCP

1. Make sure Login Manager is running on the host system.

2. Enable XDMCP on the Xterminal and direct it to contact Login Manager on the host system.

XDMCP provides a mechanism by which Xterminals can request login services from a network host. It ensures that the Xterminal is communicating with a valid login manager, and provides the protocol for exchanging authentication information between the Xterminal and the host login manager. Documentation for your Xterminal covers the procedure for enabling XDMCP.

Limiting Access by Xterminals to a Host

1. If the /etc/dt/config/Xaccess file does not exist, copy the /usr/dt/config/Xaccess file to the /etc/dt/config directory.

2. If you have to copy Xaccess to /etc/dt/config, you must change the Dtlogin.servers: line in /etc/dt/config/Xconfig to:

   Dtlogin.accessFile: 
   /etc/dt/config/Xaccess

3. Edit /etc/dt/config/Xaccess on the host. List only those X-terminals permitted to access Login Manager.

If Xaccess is empty, any host can connect.

Using a Workstation as an Xterminal

From a command line, enter:

/usr/bin/X11/X -query hostname

The X server of the workstation acting as an Xterminal must:

• Support XDMCP and the -query command-line option.
• Provide xhost permission (in /etc/X*.hosts) to the terminal host.

Adding a Non-XDMCP Xstation Terminal

1. If the /etc/dt/config/Xservers file does not exist, copy the /usr/dt/config/Xservers file to the /etc/dt/config directory.

2. If you have to copy Xservers to /etc/dt/config, you must change the Dtlogin.servers: line in /etc/dt/config/Xconfig to:

   Dtlogin*servers: /etc/dt/config/Xservers

3. Edit /etc/dt/config/Xservers to include an entry for each terminal. The display type of each terminal must be foreign.

4. Reread the Login Manager configuration files.

When Login Manager receives a SIGHUP, it rereads Xconfig and the Xservers file (or the file specified by the Dtlogin.servers resource). If it finds a new entry, dtlogin starts managing that display. If an entry has been removed, the process associated with that entry is immediately terminated.

Example

The following lines in Xservers directs dtlogin to manage sessions on two non-XDMCP terminals.

ext1:0 NPD200X foreign
ext2:0 QCP-19 foreign

Removing a Local Display

To remove a local display, remove its entry in the Xservers file in the /usr/dt/config directory.

Adding an ASCII or Character-Display Terminal

A character-display console is a configuration in which the console is not a bitmap device.

Adding an ASCII or Character-Display Console If No Bitmap Display Is Present

1. If the /etc/dt/config/Xservers file does not exist, copy the /usr/dt/config/Xervers file to the /etc/dt/config directory.

2. If you have to copy Xservers to /etc/dt/config, you must change the Dtlogin.servers: line in /etc/dt/config/Xconfig to:

   Dtlogin*servers: /etc/dt/config/Xservers

3. Comment out the line in /etc/dt/config/Xservers that starts the Xserver. This will disable the Login Option Menu.

   # * Local local@console /path/X :0

4. Reread the Login Manager configuration files.

Adding a Character-Display Console if a Bitmap Display Exists

1. If the /etc/dt/config/Xservers file does not exist, copy the /usr/dt/config/Xservers file to the /etc/dt/config directory.

2. If you have to copy Xservers to /etc/dt/config, you must change the Dtlogin.servers: line in /etc/dt/config/Xconfig to:

   Dtlogin*servers: /etc/dt/config/Xservers

3. Edit the line in /etc/dt/config/Xservers that starts the Xserver to read:

   * Local local@none /path/X :0 

4. Reread the Login Manager configuration files.