gtpa3m0eApplication Requester User's Guide

VTAM Requirements for LU 6.2

To connect to the VTAM network, each relational database (RDB) must have an LU name defined. To define the RDB to the network, a VTAM APPL definition statement must be coded with the specified LU name to register the RDB name to VTAM. The LU name must match the LU name defined in the DB2 system bootstrap data set (BSDS). See DB2 Requirements for additional information about BSDS. If defined in the OSTG resource deck, this LU name must match the LU name used to define the DB2 system PLU to the TPF system. The name can also be defined dynamically. See Defining the Remote DB2 PLU Application for LU 6.2 for more information. Here is an example of a VTAM APPL definition statement, where TPFDB2T is the LU name:

    TPFDB2T APPL APPC=YES,
                 AUTH=(ACQ),
                 AUTOSES=1,
                 DMINWNL=10,
                 DMINWNR=10,
                 DSESLIM=20,
                 EAS=9999,
                 MODETAB=RDBMODES,
                 PRTCT=PSWDBD1,
                 SECACPT=ALREADYV,
                 SRBEXIT=YES,
                 VERIFY=NONE,
                 VPACING=10
 

Some of the keywords in the VTAM APPL definition statement are described briefly here; for detailed information about these and other keywords for the VTAM APPL definition statement, see the IBM Database 2 Version 2 Administration Guide, Volume 1 and the VTAM Resource Definition Reference Manual.

Note:
Many of the keywords on the VTAM APPL statement can be overridden by defining entries in the DB2 system communications database (CDB). See the DB2 Administration Guide Volume I for more on this relationship.

Mode Names

TPFAR requires a mode definition in the VTAM Logon Mode Table. This mode name is needed for establishing the LU 6.2 sessions between TPFAR and the DB2 system. An example of mode definition is:

TPFMOD1  MODEENT LOGMODE=TPFMOD1,SSNDPAC=X'02',RUSIZES=X'F8F8'

See the DB2 Administration Guide Volume 1, and the VTAM Resource Definition Reference for more information about mode definitions.

RU Sizes and Pacing Considerations

In order for the VTAM network to run efficiently in the distributed access environment, it is important that you carefully specify RU sizes and pacing. Suggested guidelines can be found in the Distributed Relational Database Connectivity Guide.