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IBM Expiration Dates

If your data center does not have an automated tape library management system, you must rely on the limited data set protection provided by standard IBM expiration date processing; that is, if the expiration date on the internal tape label is equal to or less than today's date, the tape can be reused. Moreover, this protection is valid only for SL tapes. No protection at all is afforded for NL, BLP or NSL tapes.

The IBM expiration date on the SL tape is supplied through a standard z/OS JCL keyword, LABEL=EXPDT=yyyy/ddd, in Julian date format. An alternative method is to supply a retention period using the RETPD=nnnn keyword, which is then translated by IBM file processing into an EXPDT value.

The IBM expiration date facility has a few major drawbacks:

• All production JCL must specify an expiration date. This requires extensive manual effort to define it initially and then to maintain it if retention requirements change.
• There is no way to extend the expiration date once a tape data set has been created.
• If tape data sets are created without an EXPDT, or if it is supplied incorrectly, data sets can be overwritten before the intended data set expiration.

More information:

Expiration Date Keyword Control - Type 9