IBM SC34-7012-01 manual Security, System definitions for recovery-related functions

vIf a user’s printer becomes unusable (because of hardware or communication problems), consider the use of alternatives, such as the computer center’s printer, as a standby.

Security

Decide the security procedures for an emergency restart or a break in communications. For example, when confidential data is at risk, specify that the users should sign on again and have their passwords rechecked.

Bear in mind the security requirements when a user needs to use an alternative terminal if a failure is confined to one terminal (or to a few terminals).

Note: The sign-on state of a user is not retained after a persistent sessions restart.

System definitions for recovery-related functions

You are recommended to use a number of system definitions to ensure that your CICS regions provide the required recovery and restart support for your CICS applications.

System recovery table (SRT)

You are recommended to specify a system recovery table on the SRT system initialization parameter. If you do not specify a table suffix on this system initialization parameter, it defaults to YES, which means that CICS tries to load an unsuffixed table (which probably won’t exist in your load libraries). There is a pregenerated sample table, DFHSRT1$, supplied in CICSTS41.CICS.SDFHLOAD, and if this is adequate for your needs, specify SRT=1$. This table adds some extra system abend codes to the built-in list that CICS handles automatically, even if you define only the basic DFHSRT TYPE=INITIAL and TYPE=FINAL macros.

If you want to add additional system or user entries of your own, modify the sample table. For information about modifying an SRT, see the CICS Resource Definition Guide.

Resource definitions for recovery

Ensure that your CICS region includes DFHLIST as one of the lists specified on the GRPLIST system initialization parameter. Included in DFHLIST are the following groups, which provide basic recovery functions:

vDFHRSEND

vDFHSTAND

vDFHVTAM

For information about the contents of these groups, see the CICS Resource Definition Guide. For information about individual resource recoverability, see Chapter 12, “Defining recoverability for CICS-managed resources,” on page 123.

System log streams and general log streams

Defining system log streams for each CICS region is the most fundamental of all the recovery requirements. A system log is mandatory to maintain data integrity in the event of transaction or system abends, and to enable CICS to perform warm and emergency restarts.

CICS uses the services of the MVS system logger for all its system and general logging requirements. The CICS log manager writes system log

104CICS TS for z/OS 4.1: Recovery and Restart Guide