gtpm1m31 | TPF V4R1 Migration Guide: 3.1 to 4.1 |
In the TPF 4.1 system, dumps can span more than one tape volume. For this reason, a standby real-time tape (RTL) or alternate (ALT) tape must be available for switching at all times. (Automatic tape mounting makes this easier by automatically mounting the next tape in the 3480 stack loader as an ALT tape.) If a tape is not available during a multiple-volume dump, the dump is aborted, and an error message is issued.
You may also need more than one tape volume to post-process a dump. In the postprocessing JCL, you can specify multiple-volume serial numbers, either on separate DD statements as shown in Example 1, or by coding multiple-volume serial numbers and coding the OPTCD=B option on the DCB parameter as shown in Example 2:
//SYS000 DD DSN=RTA.TAPE,UNIT=TAPE,LABEL=(,SL),DISP=(SHR,PASS), // VOL=SER=RTATA1 // DD DSN=RTA.TAPE,UNIT=TAPE,LABEL=(,SL),DISP=(SHR,PASS), // VOL=SER=RTATA2
//SYS000 DD DSN=RTA.TAPE,UNIT=TAPE,LABEL=(,SL),DISP=(SHR,PASS), // VOL=SER=(RTATA1,RTATA2),DCB=OPTCD=B
The OPTCD=B option of the DCB parameter causes QSAM access method to unconditionally perform volume switch whenever end-of-reel is encountered, until the volume serial list is exhausted. This allows you to control whether spanned tapes are processed by simply adding to or deleting from the list of volume serial numbers on the DD statement. You must keep track of which volumes contain which dump, and specify the volumes for postprocessing in the same order in which the tapes were written. You must also use standard label processing.
If you do not specify multiple tape volumes for postprocessing, and additional tapes are needed, the System Test Post Processor (STPP) will abend with the message:
NEXT VOLUME NEEDED TO CONTINUE PROCESSING.
STPP cannot postprocess multi-volume dumps under VM, because CMS does not support concatenation of tape data sets under OS simulation.
In the TPF 4.1 system, STPP routes all messages to the data set specified on the SYSOUT DD statement. Job-specific messages no longer display on the IBM MVS operator console.