CSL in an IMSplex

The IMS CSL reduces the complexity of managing multiple IMS systems by providing you with a single-image perspective in an IMSplex. An IMSplex is one or more IMS subsystems (control, manager, or server) that can work together as a unit.

Typically, but not always, these subsystems:

  • Share either databases or resources or message queues (or any combination)
  • Run in a z/OS® sysplex environment
  • Include an IMS CSL

Within an IMSplex, you can manage multiple IMS subsystems as if they were one system. For example, instead of entering commands on each IMS system during local online change, you can enter commands from one single point of control, and the commands run on each IMS system in the IMSplex. An IMSplex can also exist in a local, or non-sysplex, environment. Use of the CSL is optional.

An IMSplex component is an IMS-defined entity that typically runs in its own address space; it manages resources, manages operations, or facilitates communications between other IMS-defined entities. After the necessary started procedures for these components are initialized, they become IMSplex members. Examples of IMSplex components are:

  • IMS subsystems (DB/DC, DBCTL, DCCTL)
  • Resource Manager
  • Operations Manager
  • Open Database Manager
  • Structured Call Interface
  • IMS Connect
  • A DLIBATCH or DBBBATCH region
  • Repository Server (RS)

A DLIBATCH or DBBBATCH region is considered a special type of IMSplex component in that it does not interact with RMs and OMs.

A typical IMSplex environment including a CSL is shown in the following figure. There are three separate operating system (OS) images. Each OS has an IMS control region and an SCI. In addition, OS 1 has an OM and an RM, OS 2 has an OM and an ODBM, and OS 3 has an ODBM. All three OS images share a coupling facility, which has database sharing structures, a message queue structure, and a resource structure.

Figure 1. IMSplex environment including a CSL
begin figure description. This figure is described in the surrounding text. end figure description.

The CSL includes the following IMS address spaces, some of which are optional:

  • ODBM
  • OM
  • RM
  • SCI

The address spaces that can participate in an IMSplex are:

  • IMS control region address spaces
  • IMS CSL manager address spaces (ODBM, OM, RM, SCI)
  • IMS server address spaces (Common Queue Server)
  • Non-IMS address spaces
  • RS address spaces

The IMSIDs of IMS systems in the IMSplex must be unique.