Chapter 14. Sysplex terminal management 179
14.2 Sysplex terminal management environment
Sysplex terminal management is an optional function of IMS. It is enabled only when IMS is
executing in a Common Service Layer (CSL) environment with shared queues. It utilizes the
services of the Resource Manager with a resource structure to save information about, and
manage the status of, IMSplex VTAM-connected terminal and user resources, and to some
extent, transactions. Figure 14-1 shows a possible configuration of a single IMS in a CSL
environment with shared queues. The shaded area indicates those components used directly
by STM. Additional IMSs in the IMSplex would utilize the same resource and shared queue
structures.
Other IMSs on other OS/390 images would have similar configurations. Each OS/390 image
would require its own SCI address space and each may have a local Resource Manager
address space, although only one RM is required within the IMSplex. There is, of course, a
single Resource Structure and a single set of Shared Queue Structures.
Wherever there is a Resource Manager accessing the resource structure, there must also be
a Common Queue Server. A single CQS address space can provide client services to RM for
the resource structure and to IMS for the shared queue structures. CQS must reside on the
same OS/390 image as its clients (RM and IMS).
Figure 14-1 Sysplex terminal management configuration
14.3 IMSplex resources
IMS resources in an IMSplex include many different types, including IMS system address
spaces, IMS system data sets, IMS defined databases, transactions, and applications,
Resource
List Structure
LOGR
List Structures
SMQ
List Structures
OSAM
Cache Structure
VSAM
Cache Structure
Shared VSO
Cache Structures
IRLM
Lock Structure
VGR
List Structure
MNPS
List Structure
Operations
Manager
(OM)
SCI
Structured
Call
Interface
SCI
SCI
Communications
IMS
Control
Region
S
C
I
Resource
Manager
(RM)
SCI
S
C
I
Common
Queue
Server
(CQS)
180 IMS Version 8 Implementation Guide
dependent regions running application programs, VTAM and OTMA network resources, batch
and utility address spaces, and probably several more. Most of these resources have names
by which they are known to IMS. When IMS systems are cloned, or have similar definitions,
many (or all) of these names are the same throughout the IMSplex and can form the basis for
IMSplex-wide system management functions.
Sysplex
terminal
management addresses the management of a subset of these resources,
primarily those defined as part of the VTAM network. These resources, and the names they
are known by, are shown in Figure 14-2. Note that STM supports neither BTAM nor OTMA
resources.
Figure 14-2 Sysplex Terminal Resources
This figure identifies the resources managed by sysplex terminal management. Each of these
resources can be the source or destination of an IMS message, and has one or more names
associated with it. Each name represents an IMS control block. How IMS handles these
messages is determined solely by its
message destination
name, which usually represents
an anchor block from which to queue the message. Each named resource may be
represented by an entry in the resource structure.
Statically defined VTAM resources (not parallel-session ISC)
Statically defined VTAM resources are defined in the IMS system generation using the TYPE,
TERMINAL, and NAME macros, the NODE name being defined on the TERMINAL macro
and the LTERM name being defined on the NAME macro:
TYPE UNITYPE=SLUTYPE2 (for example)
TERMINAL NAME=NODEname
NAME LTERMname
Static
Dynamic
APPC
ISC
MSC
ISC
Parallel Sessions
Single Session
CF
IMSplex

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