Understanding Tape Retention › Retention Methods › Keep Date Determination › CA TLMS Keep Date

CA TLMS Keep Date

To protect tape data sets from being overwritten, CA TLMS automatically assigns a keep date to every tape data set when it is created. This means you do not have to specify EXPDT or RETPD in the JCL of every job that creates a tape data set. A keep date is automatically calculated. This keep date can later be modified, either manually or automatically, to ensure that changing retention requirements are satisfied. The keep date provides the means to assign retention based on the data set name.

The keep date is calculated as follows:

• It is a certain number of days after the creation date. CA TLMS provides the DEF system option (CAI.CTAPOPTN, member TLMSIPO), which allows you to specify:
  • The minimum number of days that specific data sets should be retained.
  • The minimum number of days that groups of data sets should be retained. You can identify the data set groups by giving any part of the data set name. Therefore, you can define the same retention period for all data sets of a specific type or application.
  • A default minimum number of days for any data set that does not match any of the specific or group entries. (A default of 7 days is provided.) This ensures that every tape data set that is created has a keep date.
• It is the same as EXPDT in the JCL, if this date comes after the date calculated above.

This method of calculation ensures that every tape data set that is created has a keep date that is at least the minimum number of days defined by the tape library administrator, but it allows the creator of the data set to extend the keep date when circumstances require it. (If your data center does not allow users to modify keep dates, CA TLMS has a technique you can use to force a specific number of days to be used for keep date generation.

Note: Although a keep date is calculated for every data set, the keep date is ignored if TRS uses another type of retention for a specific data set.

The KDATE system option can be used to determine whether JCL, if coded, overrides the default retention.

More information:

Keep Date Control - Type 2 and B