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1 CREATE
2  LINK
   Creates the LAT data links, which are connections to LAN devices,
   such as Ethernet or FDDI (fiber distributed data interconnect)
   controllers, that you want your node to use. You must have OPER
   privilege to use this command.

   Format

     CREATE LINK  link-name

3 Parameter

link-name

   Specifies a name for a LAT data link. A link name can have up to
   16 ASCII characters. The characters allowed are as follows:

   o  Alphanumeric characters: A-Z, a-z, 0-9
   o  A subset of the international character set: ASCII codes 192-
      253
   o  Punctuation characters: dollar sign ($), hyphen (-), period
      (.), and
      underscore (_)

   You can create a maximum of eight links on your local node.
   Use the SHOW LINK command for a list of the link names that are
   defined for your node.

3 Qualifiers

/DECNET
      /DECNET
      /NODECNET

   Directs LAT protocol to use the DECnet data link address (
   /DECNET) or the hardware address (/NODECNET) when starting the
   LAN controller. If you do not specify the /DECNET or /NODECNET
   qualifier, the default is that the LAT protocol will use the
   DECnet data link address.

   Note that if you enter the CREATE LINK command with the /DECNET
   qualifier and receive an error message indicating a "bad
   parameter value," it means the SCSSYSTEMID system parameter is
   set to an illegal value. To change the value of this parameter,
   use the following formula:

   (1024 * a) + n

   In the formula, a is the DECnet area and n is the DECnet computer
   number. If the value is outside the range of 1025 to 65535, the
   LAT protocol cannot start.

   When you use the /NODECNET qualifier, the LAN device driver code
   determines which address to use. For example:

   o  If SCSSYSTEMID is set to 0 but DECnet is already running on an
      Ethernet controller, the LAN device code allows LAT to use the
      same address as DECnet (AA-00-04-00-xx-xx).

   o  If SCSSYSTEMID is set to 0 and DECnet is not running, the 08-
      00-2B-xx-xx-xx address is used (a different address format is
      used if your LAN controller is supplied by a vendor other than
      Digital).

   o  If the setting for SCSSYSTEMID is the same as the DECnet node
      number and DECnet is not running, the LAN device code forces
      LAT to use the AA-00-04-00-xx-xx address.

   If DECnet is configured on the system (or if the system is part
   of a cluster), SCSSYSTEMID may contain a nonzero value. This
   is a problem only when the system has 2 or more LAN controllers
   connected to the same logical LAN.

   For example, if your system has an FDDI controller and an
   Ethernet controller, your site may be configured so that the
   FDDI ring attached to the FDDI controller and the Ethernet
   segment attached to the Ethernet controller are bridged by a
   10/100 LAN bridge (FDDI-to-Ethernet). In this configuration, it
   is impossible to run LAT over both controllers.

   In such a configuration, you must run LAT and DECnet over the
   same controller if SCSSYSTEMID is not 0. If you fail to do so,
   DECnet starts first, which in turn causes the LAT startup on
   the other controller to fail. This failure occurs because LAT
   startup tries to use the AA-00-04-00-xx-xx address (the DECnet
   LAN address) but is prevented from doing so by the data link
   layer. The LAT startup fails because DECnet is already using
   this address on a different controller. (In a single logical
   LAN, all data link addresses must be unique. In this setup,
   both controllers try to use the same address, which is then not
   unique.)

   The following command (which creates the LAT link) also fails
   because the LAN driver tries to use the address based on
   SCSSYSTEMID:

   LATCP> CREATE LINK LAT$LINK_2 /NODECNET

   If SCSSYSTEMID is set to 0, configuring LAT and DECnet on
   different controllers is possible. However, in a cluster
   environment, SCSSYSTEMID cannot be set to 0.

/DEVICE
      /DEVICE=device-name

   Specifies the LAN controller device name for a LAT data link (for
   example, XEB0:). Only one LAT data link can be associated with a
   LAN controller. If you enter the CREATE LINK command without the
   /DEVICE qualifier, LATCP attempts to find an available controller
   by using a list of possible LAT data link device names. Digital
   advises that you specify a default device name by defining the
   LAT$DEVICE logical name.

/LOG
      /LOG
      /NOLOG

   Specifies whether LATCP displays a message confirming that
   the link was created. If you do not specify the /LOG or /NOLOG
   qualifier, the default is that no message will be displayed.

/STATE
      /STATE=option

   Specifies whether the link will be available for use. STATE can
   have two options:

   ON    Specifies that the created link will be available for use
         with the LAT protocol running.

   OFF   Specifies that the created link will not be available for
         use.

   If you do not specify the /STATE=option qualifier, the default is
   that the created link will be available for use (ON).

3  Example

 LATCP> CREATE LINK NETWORK_A /DEVICE=XEB0: /STATE=ON

     The CREATE LINK command in this example creates an Ethernet
     link named NETWORK_A. It specifies the Ethernet controller
     device XEB0 for that link. The link will be available for use.

2  PORT
   Creates a logical port on your local node that connects with a
   remote device on a terminal server. Alternatively, this command
   creates a logical port on your local node that connects with a
   specific service. The service can be offered by a terminal server
   or associated with one or more dedicated ports on a remote LAT
   service node.

   You must have OPER privilege to use this command.

   Format

     CREATE PORT  [port-name]

3  Parameter

port-name

   Specifies the port name in the form LTAn:, where n is a unique
   number from 1 through 9999. If the port you specify already
   exists, LATCP returns the following error message:

   %LAT-W-CMDERROR, error reported by command executor
   -SYSTEM-F-DUPLNAM, duplicate name

   If you do not specify the port name, you must specify the
   /LOGICAL qualifier.

                             NOTES
      When creating a port, note the following:

      o  Digital recommends that you assign a logical name when
         creating a port, instead of specifying a specific LTA
         device.

      o  You cannot use the CREATE PORT and SET PORT commands,
         along with the DCL command SET TERMINAL, to change the
         characteristics of a DECserver port unless there is an
         existing LAT connection to that DECserver.

3 Qualifiers

/APPLICATION

   Specifies that a logical port on your node is an application
   port. It can be used to connect to a remote device (typically a
   printer) on a terminal server or to a dedicated port on another
   LAT service node.

   If you do not specify a port type, the default port type is
   APPLICATION.

                              NOTE
      By default, LATCP creates application LAT devices with
      the HANGUP terminal characteristic. However, if you want
      to apply the NOHANGUP characteristic to application LAT
      devices, you can do so by entering specific LATCP and DCL
      commands. For example:

      $ LCP :== $LATCP
      $ LCP CREATE PORT LTA1234
      $ LCP SET PORT LTA1234 /APPLICATION /NODE=terminal_server /PORT=server_port
      $ SET TERMINAL LTA1234 /PERMANENT /NOHANGUP

      Note that you can insert the SET TERMINAL command in the
      SYS$MANAGER:LAT$SYSTARTUP.COM file (enter the command for
      each LAT device that requires the NOHANGUP characteristic).

/DEDICATED

   Specifies that a logical port on your local node is dedicated
   to an application service. When users on a terminal server (or
   on another node that supports outgoing connections) request
   a connection to this service name, they are connected to the
   dedicated port. See the OpenVMS I/O User's Reference Manual for a
   description of programming an application service.

   After creating a dedicated port on a node, use the SET PORT
   /SERVICE command to map this port to a service.

/LIMITED

   Specifies that a logical port on your local node is limited to
   a service in the same way a port created using the /DEDICATED
   qualifier is dedicated to an application service. The difference
   is that ports created using the /LIMITED qualifier are under the
   control of the system login image (LOGINOUT.EXE) instead of an
   application program (a user who connects to a limited service and
   is assigned to a limited port receives the "Username:" prompt).

   Using the /LIMITED qualifier, you can create a limited number
   of ports and map them to a specific service offered by the host
   system. If users are logged in to all of the limited ports for
   the service, no more connections are allowed to that service
   (terminal server users receive a "service in use" message).

/LOG
      /LOG
      /NOLOG

   Specifies whether LATCP displays a message confirming that
   the port was created. If you do not specify the /LOG or /NOLOG
   qualifier, the default is that no message will be displayed.

/LOGICAL

      /LOGICAL=(NAME=logical-name[,TABLE=table][,MODE=mode])

   Specifies a logical name to be associated with the actual name of
   the created port. You must specify a logical name if you do not
   specify a port name.

                                NOTE
      If you have sufficient privileges to create a port, but lack
      the privilege to assign a logical name, the port will still
      be created.

   You can specify one of the following options for the TABLE
   keyword:

   GROUP      Places the logical name in the group logical name
              table. You must have GRPNAM or SYSPRV privilege to
              place the logical name in the group logical name table.
   JOB        Places the logical name in the jobwide logical name
              table.
   PROCESS    Places the logical name in the process logical name
              table. This is the default.
   SYSTEM     Places the logical name in the system logical name
              table. You must have SYSNAM or SYSPRV privilege to
              place a name in the system logical name table.

   You can also specify the name of a specific table. For example,
   you could specify LNM$PROCESS, which would be the equivalent of
   specifying PROCESS.

   Options for the MODE keyword are:

   EXECUTIVE   Creates an executive mode logical name. You must have
               SYSNAM privilege to create an executive mode logical
               name.
   SUPERVISOR  Creates a supervisor mode logical name.
   USER        Creates a user mode logical name.

   The access mode associated with the logical name is determined
   by maximizing the access mode of the caller with the access mode
   specified by the MODE keyword: the mode with the lower privilege
   is used.

   You cannot specify an access mode with a privilege higher than
   that of the table containing the logical name. However, if your
   process has SYSNAM privilege, then the specified access mode is
   associated with the logical name regardless of the access mode of
   the caller.

   If you omit the MODE keyword, the access mode of the caller is
   associated with the logical name.

   You can also create the port as a limited port, using the
   /LIMITED qualifier.

3  Examples

   1.LATCP> CREATE PORT LTA22: /APPLICATION

     The CREATE PORT command in this example creates an application
     port named LTA22: on a service node. You can associate the port
     with a specific printer on a terminal server (use the SET PORT
     /NODE /PORT command) or with a set of printers on a terminal
     server (use the SET PORT /NODE /SERVICE command). Or, you can
     associate the port with a dedicated port on a remote service
     node. In this case, use the SET PORT /NODE /SERVICE command,
     where the /SERVICE qualifier specifies an application service
     associated with a dedicated port on the remote node. See the
     examples for the SET PORT command.

   2.LATCP> CREATE PORT LTA21: /DEDICATED

     The CREATE PORT command in this example creates the LTA21:
     port. It will be used as a dedicated port that offers a
     specific service rather than a general timesharing service.

   3.LATCP> CREATE PORT /LOG /APPLICATION -
     _LATCP> /LOGICAL=(NAME=MAIL_PORT, TABLE=PROCESS, MODE=SUPERVISOR)

     The CREATE PORT command in this example creates an application
     port. It assigns the name of the new port to the specified
     logical name (MAIL_PORT). The logical is created as a
     supervisor mode logical name in the LNM$PROCESS_TABLE logical
     name table. LATCP displays a confirmation message.

   4.$ LCP :== $LATCP
     $ LCP CREATE SERVICE/LIMITED ONLY_ONE
     $ LCP CREATE PORT/LIMITED LTA1234:
     $ LCP SET PORT LTA1234: /SERVICE=ONLY_ONE

     This series of commands creates a limited service that allows
     only one user to log in to the system through that service.
     When a user connects to service ONLY_ONE by responding to the
     terminal server prompt (Local>), the user is assigned port
     LTA1234 and then prompted for the user name. Any user who
     attempts to connect to the same service while LTA1234 has a
     user logged in receives the "service in use" message.

2  SERVICE
   Creates a service on a service node. You must have OPER privilege
   to use this command.

   Format

     CREATE SERVICE  [service-name]

3 Parameter

service-name

   Specifies a LAT service name. By default, a service name is the
   name of the local node you defined with the SET NODE command.
   The service name can be from 1 to 16 ASCII characters in length.
   The characters allowed are as follows:

   o  Alphanumeric characters: A-Z, a-z, 0-9
   o  A subset of the international character set: ASCII codes 192-
      253
   o  Punctuation characters: dollar sign ($), hyphen (-), period
      (.), and underscore (_)

3 Qualifiers

/APPLICATION

   Specifies that the created service is an application service. An
   application service offers a specific application on the service
   node rather than a general interactive service. You can define a
   dedicated port for the service by using the CREATE PORT and SET
   PORT commands.

/IDENTIFICATION
      /IDENTIFICATION[="identification-string"]

   Describes and identifies a service. Service nodes include the
   identification string in service announcements. A service node
   announces its services at regular intervals established with the
   SET NODE command. Entering the LATCP SHOW NODE command or the
   DECserver SHOW NODE command generates a display that includes
   this identification string. By default, the identification string
   is a translation of SYS$ANNOUNCE.

   You cannot specify more than 64 ASCII characters in an
   identification string (a SYS$ANNOUNCE longer than that will be
   truncated to the first 64 characters). Enclose the string in
   quotation marks (").

/LIMITED

   Specifies that the service is a limited service, using devices
   assigned the limited characteristic and associated with (mapped
   to) this limited service. This qualifier is used in conjunction
   with the SET PORT /LIMITED command (see example).

/LOG
      /LOG
      /NOLOG
   Specifies whether LATCP displays a message confirming that the
   service was created. If you do not specify the /LOG or /NOLOG
   qualifier, the default is that no message will be displayed.

/STATIC_RATING
      /STATIC_RATING=rating
      /NOSTATIC_RATING
   Enables or disables dynamic service ratings. A dynamic service
   rating means that a LAT algorithm calculates the availability
   of a service dynamically, based on the overall level of activity
   of the node that offers the service and the amount of memory.
   When a terminal server or node requests a connection to a service
   that is offered on two or more service nodes, the requesting
   node selects the service node with the highest (most favorable)
   service rating. This selection process is called load balancing.

   The dynamic service rating, which is the default, is usually
   adequate for efficient load balancing on the LAT network.
   However, when necessary, you can use the /STATIC_RATING qualifier
   to disable dynamic service ratings so that you can specify a
   static (fixed) rating. That static rating value does not change
   until the dynamic service rating is reenabled.

   Use the static rating to direct users away from or toward your
   node temporarily. Static ratings range from 0 to 255. Specify a
   low value to make the local service node less likely to be used;
   specify a high value to make the local service node more likely
   to be used.

   If you do not specify either the /STATIC_RATING or /NOSTATIC_
   RATING qualifier, the default is that the LAT software uses the
   dynamic service rating.

   Limited and application services do not rely exclusively on
   the dynamically calculated service rating. Instead, they use
   a portion of the dynamic rating based on how many ports are
   available for the service. For example, if a limited service has
   50% of its ports available, the dynamic service rating will be
   scaled, halved, and then added to 105. When ports are available,
   the rating will always be above the value 105.

   When all ports for a limited or application service are in use,
   the rating will be based on the scaled dynamic rating and the
   number of free queue slots on the local node. The rating will
   always be less then 90.

   This rating procedure for limited and application services
   follows the terminal server rating algorithm for services and
   available ports that the service offers, while at the same time
   taking into account the availability of the node (which is the
   factor used to calculate the dynamic rating).

   If your system is licensed for a specific number of units (where
   only a fixed number of users can log in to the system regardless
   of how the login limit is set), then all dynamic ratings become 0
   when all OpenVMS license units have been consumed. (This forces
   all node service ratings to the lowest possible value when logins
   are not possible because all OpenVMS license units have been
   consumed.)

   Note as well that the LAT software transmits a service
   announcement message when a user logs in to or out of the system.
   This allows the system to more quickly provide information
   about service rating changes that result from a login or logout
   operation.

3  Examples

   1.LATCP> CREATE SERVICE/STATIC_RATING=195 SALES

     The CREATE SERVICE command in this example creates the service
     SALES on a service node. This command assigns a static rating
     of 195 so terminal servers (and nodes that support outgoing
     connections) can assess the availability of services on the
     node.

   2.LATCP> CREATE SERVICE/APPLICATION GRAPHICS

     This command creates the service GRAPHICS on the local node.
     Use the CREATE PORT/DEDICATED and SET PORT/SERVICE=GRAPHICS
     commands to create a port that is dedicated to this service.

   3.$ LCP :== $LATCP
     $ LCP CREATE SERVICE/LIMITED ONLY_ONE
     $ LCP CREATE PORT/LIMITED LTA1234:
     $ LCP SET PORT LTA1234: /SERVICE=ONLY_ONE

     This series of commands creates a limited service that allows
     only one user to log in to the system through that service.
     When a user connects to service ONLY_ONE by responding to the
     terminal server prompt (Local>), the user is assigned port
     LTA1234 and then prompted for the user name. Any user who
     attempts to connect to the same service while LTA1234 has a
     user logged in receives the "service in use" message.
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