Autoinstall for terminals, consoles and APPC connections

Autoinstall for terminals provides the ability to log on to CICS® from a logical unit (LU), known to z/OS® Communications Server but not previously defined to CICS, and to make a connection to a running CICS system.

A new connection is created and installed automatically if autoinstall for connections is enabled, and either of the following occurs:
  • An APPC BIND request or CINIT request is received for an APPC service manager (SNASVCMG) session that does not have a matching CICS CONNECTION definition
  • A BIND is received for a single session that does not have a matching CICS CONNECTION definition.

A new console is created and installed automatically if autoinstall for consoles is enabled and a CIB (Command Input Buffer sent from z/OS) is received by CICS (DFHZCNA) and the console TCTTE does not already exist.

For an introduction to autoinstall, and information about how to implement it, see Autoinstall. Writing a program to control autoinstall of LUs gives information about implementing the autoinstall user program. The CICS-supplied programs are as follows:
  • DFHZATDX, which provides autoinstall for terminals only.
  • DFHZATDY, which provides autoinstall for terminals and APPC connections.

These programs are user-replaceable, because you may need to tailor the basic function to suit your CICS environment.

Design overview

Before a z/OS Communications Server device can communicate with CICS, a z/OS Communications Server session must be established between the device and CICS. The sequence of operations is LOGON, Open Destination (OPNDST), and Start Data Traffic (SDT). CICS can also initiate the LOGON by using a SIMLOGON.

The session can be requested by:
  • Specifying AUTOCONNECT when the terminal is defined to CICS
  • A z/OS Communications Server main terminal command requesting a LOGON to CICS for a given terminal; for example, V NET,LOGON=CICSA,ID=L3277C1
  • An individual terminal operator issuing a LOGON request (LOGON APPLID(CICSA))
  • A CICS main terminal command requesting LOGON for a given terminal (CEMT SET TERMINAL(xxxx) INSERVICE ACQUIRED)
  • CICS internally requesting a LOGON; for example, to process an ATI request
  • LOGAPPL=CICS in the LU statement.

Consoles are not z/OS Communications Server resource but they use a similar mechanism to autoinstall the TCTTE.

The following topics describe the processing flows in details:

Modules

ZC (terminal control) together with the following:

Module Function
DFHZATA Autoinstall program
DFHZATA2 Console autoinstall program linkedits with DFHZATA
DFHZATD Autoinstall delete program
DFHZATDX Default autoinstall user exit

The DFHZATDX module provides user input to autoinstall processing. This module is a component of ZCP, and is the default autoinstall user program (that is, it is used if you choose not to provide your own). For further information about the DFHZATDX sample program, see The autoinstall control program for terminals.

DFHZATDX is also called when creating and deleting shipped terminals (skeletons).
DFHZATDY Sample autoinstall user exit

DFHZATDY is a sample autoinstall user-replaceable program. You must modify it before you can use it. Its main function is to choose a template connection to be used in creating the new autoinstall connection clone. It also has to choose a name for the new connection. For further information about the DFHZATDY sample program, see Writing a program to control autoinstall of APPC connections.

DFHZATDY is also called when creating and deleting shipped terminals (skeletons).
DFHZATR Autoinstall restart program
DFHZATS Remote autoinstall|delete program
DFHZCTRI Trace interpretation for DFHZGAI
DFHZGAI APPC-specific autoinstall functions

z/OS Communications Server exits

A z/OS Communications Server exit is a special-purpose user-written routine that is scheduled by z/OS Communications Server when the requested operation is complete. z/OS Communications Server creates a trace record when the exit is given control.

RE entries represent RPL exits except SEND, RECEIVE, OPNDST, and CLSDST. UE entries represent non-RPL and asynchronous exits SCIP, LOGON, and LOSTERM. For more information, see z/OS Communications Server: SNA Programming.

Trace

The following point IDs are provided for the autoinstall programs (DFHZATA, DFHZATD, DFHZATR, and DFHZATS), as part of terminal control:
  • AP FC80 through AP FC8C, for which the trace levels are TC 1 and TC 2.
The following point IDs are provided for APPC autoinstall:
  • AP FA00 to FA21, for which the trace levels are TC1 and TC2.
The following point IDs are provided for console autoinstall:
  • AP FCF0
  • AP FCA3 to FCA7
RE and UE trace points are recorded when the z/OS Communications Server trace API option is requested by: 
F NET,TRACE,TYPE=VTAM,OPTION=API,MODE=EXT

GTF must have been started with the USR option.

Each z/OS Communications Server exit routine in CICS sets an ID byte in the TCTTE exit trace field (TCTEEIDA).

VTAM® is now z/OS Communications Server.

Reference