Administering MFS

To take full advantage of the flexible message formatting options offered by MFS and to ensure efficient MFS operation, an MFS administrator should be appointed.

The MFS administrator should be responsible for MFS implementation and administration and should coordinate MFS application design and programming for the installation.

The responsibilities of an MFS administrator include:

  • Establishing procedures for the submission of MFS control block requests by application development personnel.
  • Establishing procedures and controls for the application of changes to the IMS.TFORMAT library.
  • Defining MFS control blocks most efficiently in keeping with the requirements of the specific application and the overall system.
  • Minimizing device character transmission, sharing MFS control blocks, and ensuring the most efficient use of MFS without jeopardizing application requirements or operator considerations.
  • Establishing and documenting operator guidelines and system standards for MFS. The many options that MFS offers can result in confusing practices, unless you establish and follow standard procedures. Be sure to standardize certain aspects of format design in order to minimize terminal operator training and error rates.
  • Deciding if and how the optional index directory should be used and determining buffer pool requirements.
  • Monitoring the use of the MFS control blocks and of the MFS buffer pool with the IMS /DISPLAY command and IMS Monitor report output, and modifying MFS parameters as required.
  • Making end users aware of the operating characteristics of the different device types and terminal subsystems.
  • Informing others about the differences between the various partition formats.
  • Establishing and informing others about naming conventions and guidelines. In particular, the MFS administrator should be able to discuss naming conventions for the partition descriptor blocks and the sizes of the display screen, the viewports, and the display characters.
  • Communicating information on conventions for and restrictions on MFS formats.
  • Defining screen sizes and feature combinations that are not included in the IMS stage–1 system definition.
  • Creating the MFS device characteristics table control statements for processing by the MFSDCT utility (DFSUTB00). The MFS device characteristics table entries and default format control blocks are used for ETO terminals.
  • Defining input message field edit routines and segment edit routines. MFS and all MFS-supported devices are able to use message edit routines. You can use these exit routines for such common editing functions as numeric validation or conversion of blanks to zeros.

    IMS provides a sample of both a field edit and a segment edit routine.

  • Determining whether MFS verifies the protected fields that are returned by 3270 and SLU2 devices. If MFS detects that the content of the protected fields that are returned from the devices are different from the content of the fields that were transmitted to the devices, MFS ignores the returned fields. The MFS administrator specifies whether MFS verifies the protected data fields by configuring the DFSDCxxx member of the IMS PROCLIB data set.

The MFS administrator should be technically competent in all aspects of IMS relative to MFS:

  • Online transaction processing
  • IMS API for message processing
  • Operation with remote controllers
  • MFS implementation, device characteristics, and capabilities
  • Interpretation of MFS statistics and related IMS Monitor report output

The administrator should also be familiar with the hardware and remote programs for SLU-P, Finance remote programs, or ISC subsystems if such programs are going to operate with MFS by using distributed presentation management.

In addition, because one administrative responsibility is minimizing device character transmission, the administrator should be familiar with the terminal hardware characteristics.

An MFS administrator must communicate with IMS system administrators and application developers, as well as programmable workstation developers and end users. The administrator must be able to enforce installation standards and to modify application specifications for MFS control blocks when necessary to benefit overall system performance. The procedures of related programming groups should recognize this authority of the MFS administrator.