FDRTSEL Features and Considerations

This section describes some special features of FDRTSEL, and considerations for using the features of FDRTSEL.

LASTAPE support

FDRTSEL has LAST TAPE (LASTAPE) support, similar to the LASTAPE option in FDRABR (described in “LAST TAPE Option” in Archive-and-Superscratch-Job-Control-Requirements). LASTAPE support allows you to add new files onto a tape created by a previous execution of FDRTSEL in a previous step or job, even if that job was run on an earlier day. LASTAPE works only with tape output.

To use LASTAPE, change the data set name in the TAPEOUT and/or TAPE2OUT DD statements to include a qualifier of “LASTAPE” anywhere in the name, for example, “DSN=PROD.ARCHIVE.LASTAPE” or “DSN=TECH.LASTAPE.DAILY”. You must also change the disposition to DISP=(MOD,KEEP).

If FDRTSEL finds a LAST TAPE (LASTAPE) data set name, it invokes special processing to keep track of the last tape used for output so that it can add files to that tape:

• At the end of processing, after all files have been written to the output tape, FDRTSEL writes a dummy (empty) file with the LASTAPE DSNAME as the last file on that output tape, and catalogs it for reference.
• At the start of processing, FDRTSEL does a LOCATE on the name to get the tape volume and file number from the catalog. FDRTSEL then uncatalogs the backup (in case of abend) and opens the file to verify that it is still on the tape. If the LOCATE or the OPEN fails, FDRTSEL assumes that the last tape is not usable and starts outputting to a fresh scratch tape.
• If the LAST TAPE (LASTAPE) file is successfully opened, FDRTSEL adds new files to the tape. It overwrites the LASTAPE file unless the TMS (tape management) option is specified on the CONTROL statement or is set in the FDR Global Options (ISPF panel A.I.4.4), in which case it starts just beyond the LASTAPE file.

If you change the DISP to (NEW,KEEP), it uncatalogs the LASTAPE file (if it exists) but starts outputting to a fresh scratch tape without trying to open the file, allowing you to specify when to add files to the LASTAPE and when to start fresh by simply changing the DISP. Alternately, you can uncatalog the LASTAPE file and the next FDRTSEL run using that name uses a scratch output.

DASD to DASD operations

When the TAPEOUT or TAPE2OUT DD statement points to a DASD volume, FDRTSEL uses this DD statement only to identify what volumes to use to receive the output files; data set name and other parameters on the DD statement are ignored. Internally, it determines the available free space on all DASD volumes identified by the TAPEOUT DD statement and dynamically allocates a work DD statement with the DASD volumes in the order of largest available free space. FDRTSEL recomputes the available free space and resets the order of the output volumes after each archive backup file is successfully copied (the NOPOOL operand on the CONTROL statement overrides this sorting and use the volume in the order specified). FDRTSEL-JCL-Requirements has more information on the DD statement used with DASD output.

If the output copy number (specified by ABRCOPY= or ABRCOPY2=) is different from input backup, FDRTSEL simply copies the requested backup files to the new output volumes. But if the output copy number is the same as the input, then FDRTSEL copies the selected files to the new volume serial numbers with a copy number of “0”. If the copy is successful, FDRTSEL scratches the input file from the DASD volume, and then RENAMEs the “0” copy to the original copy number. The Archive Control File is updated appropriately.

DASD to DASD functions default to EXP=COPY to preserve the expiration date on DASD. The input files selected by FDRTSEL for DASD to DASD must be cataloged and you must not specify CAT=NO. If CAT=NO is specified, this can cause the source TAPEIN file to be scratched and the file it was copied to is not renamed properly.

Just like FDRABR POOLDISK functions, FDRTSEL allows you to create a pool of volumes to be used in selection for the output of the DASD to DASD copy. You can define DASD pools for the TAPEOUT DD statement by creating catalog entries pointing to the volume serial numbers or just allocated them via the JCL.

Checkpoint / Restart

FDRTSEL includes an option to checkpoint all of its processing, and to restart if it is interrupted. This is useful for long FDRTSEL jobs to avoid repeating operations already completed.

If the optional TSELCKPT DD statement (see “TSELCKPT DD Statement” in FDR-and-ABR-Backup-Maintenance) is present, FDRTSEL records on this data set:

• All control card information (all options and selection criteria),
• A list of all backups selected (to be processed),
• If ARCEDIT is used, a list of all data sets selected from within each backup, and
• A completion record for each backup successfully processed.

During initialization, if the TSELCKPT data set is empty or new, FDRTSEL assumes normal operation and initializes the data set with the information listed above. If FDRTSEL completes normally, it rewrites the checkpoint file as empty, ready for reuse by the next FDRTSEL execution.

If FDRTSEL is stopped or shutdown before completion due to an abend, MAXFILES, operator cancellation, or the console commands described below, the checkpoint file contains all of the information to restart FDRTSEL after the last successfully copied file. When the FDRTSEL job is resubmitted, and the TSELCKPT DD statement points to the existing checkpoint file, FDRTSEL detects that the file is NOT empty and begins recovery processing automatically. It loads the selection criteria from the checkpoint file, ignoring the criteria in the job stream, and processes the entire selection list again. Before copying a backup, FDRTSEL checks to see if there is a completion record in the checkpoint for that backup. If so, it displays the original completion date and time and bypasses the backup. Any backup not recorded as completed is processed.

Operator commands

FDRTSEL has an operator communications function that allows you to STOP a currently running FDRTSEL job and display the STATUS of an FDRTSEL job.

You can direct FDRTSEL to terminate after completing processing on the current input file by issuing either the console MODIFY (F) or STOP (P) command, substituting the job name of the FDRTSEL job:

F job,STOP P job

To request that FDRTSEL display on the console number of files selected for copying and the current file being copied, issue the MODIFY (F) command:

F job,STATUS

Consolidating ARCHIVE tapes

An important function of FDRTSEL is the maintenance of your library of archived data on tape. Since archived data sets are usually kept for a long time, a year or more, the number of tape volumes devoted to archived data may become large. However, depending on how you create and managed your archived data, much of the data on those tapes may become obsolete, resulting in waste. This can occur if:

• Your have data sets with varying expiration dates on the same tapes. This is especially likely if you use the SMSEXPIRE=YES function (see “SMSEXPIRE=” in Archive-DUMP-and-SCRATCH-Statements).
• You discard archived data sets that are no longer cataloged (such as GDGs).
• You do not keep the archived copies of data set after they have been recalled.

In these cases, you want to periodically copy all or part of your archive library in order to discard the tape data that is no longer needed and consolidate the remainder onto a smaller set of tape volumes.

When you run FDRTSEL with SELECT ARCHIVE, it selects only those archive backup files that still have entries in the Archive Control File, so other backups on the input tapes are not copied and the output tapes contain less data.

SELECT ARCEDIT works much the same way, except that while copying the remaining backup files, the DASD data sets in those backups are “edited” so that only those data sets that had entries selected from the Archive Control File are copied; data sets that have been purged from the Archive Control File (or were not selected) are discarded, further reducing the size of those backup files that remain.

The most straightforward way of consolidating archive tapes is to maintain your Archive Control File by periodically running the FDRARCH utility (see Archive-Maintenance-Utility-FDRARCH) with appropriate parameters to delete the entries for obsolete data sets, such as expired backups, restored data sets, uncataloged data sets, or whatever other options your installation's policy requires. Then run FDRTSEL to copy only the archive data for the data sets that remain in the Archive Control File. See “Tape Consolidation Example” in FDRTSEL-ARCHIVE-Examples .