IBM SC34-7012-01 manual Designing the end user’s restart procedure, End user’s standby procedures

Before any design or programming work begins, all interested parties should agree on the statement—including:

vThose responsible for business management

vThose responsible for data management

vThose who are to use the application—including the end users, and those responsible for computer and online system operation

Designing the end user’s restart procedure

Decide how the user is to restart work on the application after a system failure.

About this task

Points to consider are:

vThe need for users to re-identify themselves to the system in a sign-on message (dictated by security requirements, as discussed under question 4 in “Questions relating to recovery requirements” on page 101).

vThe availability of appropriate information for users, so that they know what work has and has not been done. Consider the possibility of a progress transaction.

vHow much or how little rekeying will be needed when resuming work (dictated by the feasibility of rekeying data, as discussed under question 9 in “Questions relating to recovery requirements” on page 101).

When designing the user’s restart procedure (including the progress transaction, if used) include precautions to ensure that each input data item is processed once only.

End user’s standby procedures

Decide how application work might continue in the event of a prolonged failure of the system.

For example, for an order-entry application, it might be practical (for a limited time) to continue taking orders offline—by manual methods. If you plan such an approach, specify how the offline data is to be subsequently entered into the system; it might be necessary to provide a catch-up function.

Note: If the user is working with an intelligent workstation or a terminal attached to a programmable controller, it may be possible to continue gathering data without access to a CICS region on an MVS host system.

Communications between application and user

For each application, specify the type of terminal the user is to work with.

Decide if you will provide special procedures to overcome communication problems; for example:

vAllow the user to continue work on an alternative terminal (but with appropriate security precautions, such as signing on again).

vIn cases where the user’s terminal is attached to a programmable controller, determine the recovery actions that controller (or the program in it) is capable of providing.

Chapter 10. Planning aspects of recovery 103