Telnet uses application LUs that are defined in VTAM® application (APPL) major nodes
to represent clients.
Before you begin
You can code LU definitions in the data set members of your
choice. You must include the data set that contains your member updates
in the list of data sets that is specified on the VTAMLST DD statement
in the procedure that is used to start VTAM.
Including this data set in the list ensures that the LUs are available
for activation after VTAM is
started.
Procedure
Perform the following steps to customize the VTAM configuration data set:
- Automatically activate the application definition deck
by including it in ATCCONxx.
- Define the LUs in a VTAM data
set member. A sample VTAM configuration
data set is in SEZAINST(IVPLU).
Tip: In the VTAM configuration data set, you can define
Telnet LUs that represent either terminal or printer emulators with
a wildcard character instead of coding individual Telnet application
LU statements. The Model Application Names function enables you to
code a model APPL name with an asterisk (*) or a question mark (?)
(see
z/OS Communications Server: SNA Resource Definition
Reference for more information). Use * as a wildcard
character to replace a character string. For example, if you need
Telnet LUs in the range TCPABC01-TCPABC99, then you can add a single VTAM application definition statement
to the sample configuration data set. The definition statement has
the Telnet application minor node (Telnet LU) name TCPABC*, which
supports all 99 LUs.
- Use the default value YES for the SESSLIM parameter. Telnet server LUs do not support multiple concurrent sessions.
- Code LOSTERM=IMMED on all target (PLU) applications that
will have a SNA session with Telnet. If you do not code
this value, CLOSEACB might stop while it is waiting for UNBIND RESPONSE
if the target (PLU) application does not issue CLSDST when the LOSTERM
exit is processed.
- Code EAS=1 to minimize Common Service Area (CSA) storage
use. If you use the default value for EAS, excessive CSA
storage will be used.
- Use the default VTAM value
NO for PARSESS. You should not use parallel sessions with
Telnet LUs.
Results
When you are done, start VTAM.
Put the LUs in a connectable state by activating the APPL major node
that represents the Telnet LUs. Issue the D NET,MAJNODES command or
the D NET,ID=appl_major_node_name command
to verify that your APPL major node is active.