Designing for TSO Data Backup and Space Management

The following two management classes must be defined for TSO data:

EXTBAK
INTERIM

EXTBAK defines the availability and space management attributes for long-term libraries that contain JCL, source program, CLIST, object, and load modules. Because the Partial Release attribute is set to CI (conditional immediate), any primary space that is allocated, but not used, is released immediately if a secondary space request is specified. EXTBAK retains these data sets on primary storage indefinitely if they are referenced at least once every 15 days, as dictated by the value of MIGRATE PRIMARY DAYS NON-USAGE. If 15 days elapse without the data set being referenced, DFSMShsm moves the data set to migration level 1 where the data set exists for 60 days before being written to migration level 2. The attribute, Number Backup Versions, Data Set Exists, indicates that the five most recent versions of the data set are retained by DFSMShsm on backup volumes as long as the data set exists.

INTERIM defines the space management attributes for short-term programmer listings. Because Partial Release is set to I (immediate), any primary space that is allocated, but not used, is released immediately, because these are transient data sets. DFSMShsm deletes them after three days, regardless of their usage, based on the value of the Expire after Date/Days attribute. No backup versions are initiated, because Auto Backup is set to NO.

Table 1 shows the attributes for these two management classes.

Table 1. Management Classes for TSO Data
Attributes	Management Classes
Name	EXTBAK	INTERIM
Expire after Days Non-usage	NOLIMIT	3
Expire after Date/Days	NOLIMIT	3
Retention Limit	NOLIMIT	3
Partial Release	COND IMMED	YES IMMED
Migrate Primary Days Non-usage	15	3
Level 1 Days Non-usage	60	60
Command or Auto Migrate	BOTH	BOTH
# GDG Elements on Primary	—	—
Rolled-off GDS Action	—	—
Backup Frequency	0	—
Number Backup Versions, Data Set Exists	5	—
Number Backup Versions, Data Set Deleted	1	—
Retain Days Only Backup Version	60	—
Retain Days Extra Backup Versions	30	—
Admin or User Command Backup	BOTH	—
Auto Backup	YES	NO
Backup Copy Technique	STANDARD	STANDARD

FILTLISTs define long-term programmer data and SYSPRINT output from programmer's jobs. These data types are identified by the value of the data set's LLQ. Figure 1 shows the FILTLIST section needed to identify the TSO data sets.

Figure 1. FILTLISTs for TSO Data Used in Management Class ACS Routine

FILTLIST PGMRLIST            INCLUDE('SYSOUT',LIST*,OUT*)
FILTLIST PGMRDATA            INCLUDE('ASM',COB*,FOR*,'CNTL','JCL','PLI',
                                    'PL1','SCRIPT','TEXT','CLIST','SRC',
                                    'SOURCE',LOAD*,'PGMLIB','RESLIB')

Figure 2 shows the mainline logic needed to assign the management classes. When the LLQ of the data set being allocated satisfies one of literals or masks listed in the FILTLIST statement, the management class, EXTBAK or INTERIM, is assigned to the system-managed data set. Any TSO data sets that do not have LLQs matching either PGMRDATA or PGMRLIST are assigned the STANDARD management class. This is done by the last OTHERWISE clause in the management class ACS routine. See the management class ACS routine in Sample Classes, Groups, and ACS Routines for an example.

Figure 2. Management Class ACS Routine for TSO Data

  WHEN (&LLQ = &PGMRDATA)                  /* Backup application      */
   DO                                     /* development data        */
     SET &MGMTCLAS = 'EXTBAK'             /* frequently              */
     EXIT
   END
 WHEN (&LLQ = &PGMRLIST)                  /* Give 'short life' to    */
   DO                                     /* programmer listings     */
     SET &MGMTCLAS = 'INTERIM'
     EXIT
   END