Change the device name in a DDU definition by using the RENAME command. The following command changes the device name of terminal TTE6 to TTE7. DDU displays a confirmation message when the device name is renamed.

DDU> RENAME TTE6 TTE7 Device TTE6 has been renamed to device TTE7

A device name can be a logical name, a physical device name, or a group device name. See Table 2-1 for a list of DDU group device names.

Change the login characteristics of a device by using the /[NO]CONTROLLED and /[NO]AUTOLOGIN qualifiers with the RENAME command. See Section 2.10 and Section 2.5.1 for descriptions of these qualifiers.

You cannot use the RENAME command to modify the default DDU definition. See Chapter 17 for more information on the RENAME command.

2.7 Removing DDU Definitions

If you want to restrict a terminal from accessing ACMS, use the REMOVE command to remove its device definition from the DDU authorization file. The REMOVE command deletes the device definition and displays a message confirming the deletion. The following command removes the DDU definitions for all LAT terminals:

DDU> REMOVE LT Device LT has been removed from the database

A device name can be a logical name, a physical device name, or a group device name. See Table 2-1 for a list of DDU group device names. See Chapter 17 for more information on the REMOVE command.

2.8 DDU DEFAULT Definition

The DDU command DEFAULT changes information in the DDU default definition. When you use the ADD command without any qualifiers, all new terminals receive the characteristics defined in the DDU default definition. The ADD command is the only command affected by the DDU default definition.

The first time you run DDU, the DDU default definition specifies that terminals receive the Not Controlled and No Autologin sign-in characteristics. You can use the /[NO]CONTROLLED, /[NO]AUTOLOGIN, and /PRINTFILE qualifiers with the DEFAULT command to change characteristics in the default definition.

The following DEFAULT command changes the DDU default definition so that new terminals receive the Controlled sign-in characteristic. You can use the /NOCONTROLLED qualifier to override the default definition. DDU displays a confirmation message when this command executes.

DDU> DEFAULT/CONTROLLED Device(s) has been modified

You can display the sign-in characteristics currently defined in the DDU default definition by using the DDU command SHOW and specifying DEFAULT as a device name. For example:

DDU> SHOW DEFAULT Device Name: DEFAULT CONTROLLED No Autologin Printfile:

The output display tells you that the default sign-in characteristics are Controlled, No Autologin, and No Printfile. All new terminals added with the ADD command without qualifiers are designated as ACMS-controlled terminals with automatic sign-ins disabled and No Printfile.

See Section 2.9 and Chapter 17 for more information about the SHOW command.

2.9 Displaying DDU Definitions

When you add or change device information, you can verify the terminal names and sign-in characteristics in the device authorization file with the DDU SHOW command. Specify a device name with the SHOW command to display all definitions that contain a particular device name, or use the wildcard character (*) to display all current DDU definitions. Example 2-1 shows the output from the SHOW command.

Example 2-1 DDU SHOW Command

DDU> SHOW * Device Name: $ALL NOT CONTROLLED Printfile: Device Name: DEFAULT CONTROLLED No Autologin Printfile: Device Name: LT NOT CONTROLLED No Autologin Printfile: Device Name: LTA12 CONTROLLED Autologin Username: SMITH Printfile: Device Name: TT NOT CONTROLLED No Autologin Printfile: Device Name: TTE5 NOT CONTROLLED No Autologin Printfile: SPOOLDEV::TXA0: Device Name: TTE6 CONTROLLED Autologin Username: TURKLES Printfile: Device Name: VTA65 NOT CONTROLLED No Autologin Printfile:

The SHOW command displays the name of the device, the sign-in characteristic of the device (whether it is controlled or not controlled), whether the autologin option was chosen for sign-in, whether a Printfile option was used and, if so, which one: print-file-spec or spooled-device-name. If the autologin option was chosen for sign-in, the user name used for automatic sign-in also appears.

To have the device information written to a file instead of displayed on a terminal, use the DDU command LIST. See Chapter 17 for more information about the LIST and SHOW commands.

2.10 Defining ACMS-Controlled Terminals

You can define local and LAT terminals as ACMS-controlled terminals. Specify the /CONTROLLED qualifier with the ADD, COPY, DEFAULT, MODIFY, or RENAME commands to control ACMS terminals. The /CONTROLLED qualifier assigns the sign-in characteristic Controlled to a terminal.

The following ADD command creates a device definition with the Controlled sign-in characteristic for local terminal TTE6:

$ RUN SYS$SYSTEM:ACMSDDU DDU> ADD TTE6 /CONTROLLED Device TTE6 has been added to the database DDU> EXIT $

The following ADD command creates a device definition with the Controlled sign-in characteristic for LAT terminal LTA11:

$ RUN SYS$SYSTEM:ACMSDDU DDU> ADD LTA11 /CONTROLLED Device LTA11 has been added to the database DDU> EXIT $

You can only use the /CONTROLLED qualifier with physical device names or the group device names LT or TT. You receive an error if you use the /CONTROLLED qualifier for definitions with the group device names $ALL, PT, RT, and VT.

To release a terminal from ACMS control, use the /NOCONTROLLED qualifier with the MODIFY command. See Section 2.5 for information about the MODIFY command.

ACMS makes use of login features set by the OpenVMS AUTHORIZE command. Table 2-2 lists the AUTHORIZE qualifiers affecting sign-in to ACMS-controlled terminals.

Table 2-2 OpenVMS AUTHORIZE Qualifiers Affecting Sign-in to ACMS-Controlled Terminals

Qualifier	Description
/PASSWORD=(password1 [,password2])	Allows for processing of multiple passwords.
/FLAGS=DISUSER	Disables account.
/EXPIRATION=time	Sets user account expiration.
/ACCESS	Checks user day and hour restrictions.
/FLAGS=DISREPORT	Disables the display of the last date and time of interactive and non-interactive sign-ins. Also disables the display of the number of failed sign-ins since the last successful sign-in.
/FLAGS=DISNEWMAIL	Disables the display of the number of new mail messages.

2.11 Authorizing LAT Terminal Ports as Controlled Terminals

You can use DDU to authorize two types of LAT terminal ports as controlled terminals:

• Application ports
  With an application port, control passes to ACMS as soon as a key is pressed.
• Dedicated service ports
  With a dedicated service port, control passes at the connection to the dedicated service associated with ACMS.

Use LATCP to create both application ports and dedicated service ports. Application ports are mapped directly to a physical port on a specific terminal server, while dedicated service ports are mapped to a service name which may be available on a number of nodes. A dedicated service port does not necessarily map to any specific physical terminal port. Rather, a physical terminal becomes associated with an available dedicated service port name (LTAn:) when that terminal's user connects to the service with which the port is associated (the service to which it is "dedicated").

From a user perspective, there are two major differences between LAT application ports and dedicated service ports:

• User sign-in
  An application port which is an ACMS-controlled terminal requires only that the user press any typing key to begin signing in to ACMS. When using a dedicated service port as an ACMS-controlled terminal, the user must connect to a predetermined LAT service before pressing any key to begin the ACMS sign-in.
• Connections to other LAT services
  An application port which is an ACMS-controlled terminal gives access only to ACMS. With a dedicated service port, the terminal can be used for purposes other than ACMS application. The user can connect to other LAT services and the terminal is only controlled by ACMS if the user connects to the LAT service being used by ACMS.

When deciding which type of LAT terminal to use as an ACMS-controlled terminal, there are two major factors to consider:

• Availability
  If the terminal server to which a controlled terminal (application port) is connected suffers a power failure, that terminal can not function again as a controlled terminal until ACMS/STOP TERMINALS and ACMS/START TERMINALS commands are issued. This means that all ACMS terminal users have to be interrupted before those affected by the power failure can continue working.
  In contrast, dedicated service ports continue to be available as controlled terminals as soon as the terminal server has recovered from the power failure; no intervention is required. If this kind of availability is an important issue, dedicated service ports would be the best choice.
• Versatility
  When an application port is an ACMS-controlled terminal, it cannot be used for anything else. To do so would require "uncontrolling" it by setting the /NOCONTROLLED attribute in ACMSDDU and issuing the ACMS/RESET TERMINALS command. Dedicated service ports, however, are not actually controlled by ACMS in the same sense that application ports are. A dedicated service port which is a controlled terminal behaves in the same way that an application port does once the user chooses to connect to the appropriate service. But the user can also connect to any other service which is available to the terminal server. As a result, dedicated service ports are a better choice if you wish to use the same terminal for ACMS and non-ACMS work on a regular basis. Conversely, application ports would be a better choice if you wish to restrict a terminal to ACMS use exclusively.

As described in Section 2.10, you can use the /CONTROLLED qualifier to define LAT terminals as ACMS-controlled terminals. However, before you can control a LAT terminal, you must use the OpenVMS LAT Control Program (LATCP) Utility to define the terminal as an applications port or a dedicated service port and map the port to a terminal server. The following sections explain how to do this.

2.12.1 LAT Setup for an Applications Port

After you have used ACMSDDU to specify that certain terminals are controlled, take the following steps to define the terminal as an applications port:

1. Invoke the LATCP Utility and use the LATCP command CREATE PORT with the /APPLICATION qualifier to define the LAT terminal as an applications port. For example:

   $ RUN SYS$SYSTEM:LATCP LCP> CREATE PORT LTA11: /APPLICATION

2. Use the SET PORT command to map the LAT terminal to a port on the terminal server and then exit from the LATCP Utility:

   LCP> SET PORT LTA11: /APPLICATION /NODE=SAILS /PORT=PORT_1 LCP> EXIT

   
   This command specifies that the applications port LTA11 is associated with the port named PORT_1 on the server named SAILS.

3. To use a LAT terminal as an application port, you must set access on the corresponding physical port to remote. Use the SHOW PORT command at the terminal server's "Local>" prompt to determine the access type of the LAT terminal at which you are working. If your terminal is defined as a local or dynamic LAT terminal, you must redefine your terminal to be remote by using the DEFINE PORT command. This command is a privileged LAT command that requires you to use the SET PRIVILEGED command and enter the server's privileged password to enable LAT privileges.
   Use the following commands to define your port to be remote:

   Local> SHOW PORT Local> SET PRIVILEGED Password> Local> DEFINE PORT <port-number> ACCESS REMOTE

4. Use the DCL SET TERMINAL command to set the device type of the terminal and the ACMS/RESET TERMINALS command to set the new terminal characteristics:

   $ SET TERMINAL LTA11 /PERM /DEVICE=VT200 $ ACMS/RESET TERMINALS

   
   LTA11 can now be used as an ACMS-controlled terminal. See VMS LAT Control Program (LATCP) Manual for more information about LAT terminals.

Instead of using this sequence of commands to define LAT terminals each time you start OpenVMS, you can create a command file of LATCP Utility commands. Create a file called LAT$SYSTARTUP.COM in SYS$MANAGER, and include the commands. OpenVMS provides you with a template LAT definition command file, LAT$SYSTARTUP.TEMPLATE, which is copied to SYS$MANAGER when you install OpenVMS.

2.12.2 LAT Setup for a Dedicated Service Port

Creating a LAT dedicated service port involves the following steps, which are discussed in the following sections:

• Setup of the terminal server port (using terminal server local mode at the "Local>" prompt )
• Creation of a service (using LATCP)
• Creation of dedicated service ports (using LATCP)
• Association of the dedicated service with the desired service (using LATCP)

Dedicated service ports which are used as ACMS-controlled terminals should be placed in local access mode:

Local> SHOW PORT Local> SET PRIVILEGED Password> Local> DEFINE PORT <port-number> ACCESS LOCAL

See Section 2.12.1 for a description of DEFINE PORT.

You may want to make the service which will be used for dedicated service port connections the preferred service for a LAT terminal which will be controlled by ACMS. Once the preferred service attribute is in effect, the specified service becomes the default parameter of the LAT CONNECT command. This means that the ACMS user can connect to an ACMS application by following this sequence:

1. Enter the CONNECT command at the "Local>" prompt
2. Press [Return]
3. Press any typing key

This minimizes the difference between the two types of controlled terminals. Preferred service setup is accomplished with the following commands:

Local> SET PORT <port-number> PREFERRED <service name> Local> DEFINE PORT <port-number> PREFERRED <service name>

The SET PORT command takes effect immediately and lasts only until the current user logs out of the terminal server. If you wish to make any port attribute last beyond the current login, you must also use the DEFINE PORT command.

As a further convenience to the ACMS user, you may wish to enable the Autoconnect port attribute. This has two results:

• When a new LAT login is initiated, the terminal server will automatically attempt to connect to the preferred service (if one has been defined).
• If the user attempts to connect to any service which is not currently available, the terminal server will periodically attempt to connect to that service for the user.

The LAT commands used to enable the Autoconnect attribute are:

Local> SET PORT <port-number> AUTOCONNECT ENABLED Local> DEFINE PORT <port-number> AUTOCONNECT ENBABLED

2.12.2.2 Creation of a Service

Terminal servers make various nodes or applications running on those nodes available to all the terminals connected to the server. A node or application known to a terminal server is called a LAT service.

Dedicated service ports must be associated with a LAT service before they can be used. The following LATCP command creates a service named ACMS_SERVICE:

LCP> CREATE SERVICE /APPLICATION ACMS_SERVICE

The service type (APPLICATION) and service name (ACMS_SERVICE) will be referred to later when setting up dedicated service ports in LATCP. You can also associate a dedicated service port with a service which is a node. This can create complications for other LAT terminal users on the node in question, however, and is not recommended for that reason. For example, if you associate a node name with a dedicated service port and not all dedicated service ports are currently in use, no one will be able to connect to that node from the "Local>" prompt without ACMS controlling the terminal.

Care should be taken when creating service names on particular nodes. If a given service is defined on two different nodes known to the terminal server in use, connections will only complete to the node on which the service has the highest rating. If the ACMS Terminal Subsystem Controller (TSC) is not started on the node on which the connection is completed, no connection will occur (unless a program running on the node happens to have opened a channel to the terminal --- in that case, the connection will be established and the terminal will be usable by that program). If the service is defined on different nodes with the same static rating, it is unpredictable which node will receive a given connection. Therefore, it is recommended that each service be defined on only one node unless ACMS (including TSC) will generally be started on all nodes on which the service is defined.

2.12.2.3 Creation of Dedicated Service Ports

It is important to understand that there is no direct correlation between a particular physical port on a DECserver and a dedicated service port created with LATCP. When a terminal connects to a service for which dedicated service ports exist, that terminal becomes associated with an available dedicated service port name for the duration of the connection. Typically, there will be a many-to-one mapping between dedicated service ports and a service name.

If a direct correspondence between physical ports and dedicated service ports is desired, it can only be achieved by creating a service for each port, and connecting to only that service when using the given terminal.

The names of dedicated service ports must be of the form LTAn:, where n is a number. One such port name should be created for each terminal which is to be used as a controlled dedicated service port. To do this, use the following command:

LCP> CREATE PORT LTAn: /DEDICATED

2.12.2.4 Association of the Dedicated Service Port with the Desired Service

Once a dedicated service port has been created, it must be associated with a service before it can be used. This is done with the LATCP SET PORT command:

LCP> SET PORT LTAn: /DEDICATED/SERVICE=<service name>

Note that the /SERVICE qualifier cannot be used with the CREATE PORT command.