CICSPlex SM address space (CMAS)

The CICSPlex® SM address space (CMAS) is the hub of any CICSPlex SM configuration, because it is responsible for most of the work involved in managing and reporting on CICS® systems and their resources. Every CICSplex is managed by at least one CMAS. The CMAS is responsible for the single system image (SSI) that enables the operator to manage a CICSplex as if it were a single CICS system, regardless of the number of CICS systems defined as belonging to the CICSplex, and regardless of their physical location.

The CMAS implements the BAS, WLM, RTA, and monitoring functions of CICSPlex SM, and maintains configuration information about the CICSplexes it is managing. It also holds information about its own links with other CMASs. It stores this information in its data repository. (See Figure 1).

A CMAS is a full-function CICS Transaction Server for z/OS® system. Most CMAS components run as CICS tasks, and CMAS connections to other components are implemented using CICS intercommunication methods.
Note: The CMAS does not support user applications or terminals, and its resources should not be considered available for non-CMAS tasks, including (without limitation) the use of any monitoring and performance tool other than those supplied as a part of CICSPlex SM.

A CMAS cannot be running a lower release of CICS than its MASs. Also, both the CMAS and the MASs must be running the same release of CICSPlex SM.

A CMAS is not part of any CICSplex: a single CMAS can participate in the management of multiple CICSplexes, but belongs to none of them.

If a CICSplex is managed by multiple CMASs:
  • The CMASs are connected to each other by CMAS-to-CMAS links defined to CICSPlex SM. These links ensure that each CMAS can access data held by other CMASs, and a single-system image can be presented to the operators.
  • One of the CMASs is designated the maintenance point CMAS. That CMAS is responsible for maintaining all the CICSPlex SM definitions relating to a CICSplex and keeping all the data repositories in synchronization.

CICSPlex SM can issue SNA generic alerts to NetView®, provided that a CMAS is installed on the same MVS™ image as the NetView instance with which CICSPlex SM is working.