Assigning policies

DFSMSrmm provides these methods for the assignment of retention and management policies:

Specify the retention method (EXPDT or VRSEL) to be used for the tape volume set.
Use ACS routines to assign a management class to a data set to allow DFSMSrmm to:
- Retrieve and use the management class attributes relevant for tape management. DFSMSrmm calls ACS routines directly to provide support for non-system-managed tape if you have enabled it with the EDGRMMxx parmlib option SMSACS. This DFSMSrmm processing enables you to use an SMS management class to manage system-managed and non-system-managed tape data sets. Use EDGRMMxx parmlib option MCATTR to enable and tailor the usage of the management class attributes. The SMS management class attributes that can be retrieved are the expiration attributes 'Expire after Days Non-usage' and 'Expire after Date/Days'. They are bound to the DFSMSrmm data set attributes EXPDT and LASTREF when the data set is first written.
- Match a DFSMSrmm data set vital record specification to the management class name. This processing applies only when the VRSEL retention method is used. DFSMSrmm calls ACS routines directly to provide support for non-system-managed tape, if you have enabled it with the EDGRMMxx parmlib option SMSACS. This DFSMSrmm processing enables you to use an SMS management class to manage system-managed and non-system-managed tape data sets.
Define DFSMSrmm vital record specifications with data set name masks to identify the retention and movement policies. This method applies only when the VRSEL retention method is used.
Define a vital record specification management value that DFSMSrmm can use to apply retention and movement policies to data sets. Use the EDG_EXIT100 installation exit described in Using DFSMSrmm installation exits to select a vital record specification management value. You can use information in the system to determine which vital record specification management value to use. This method applies only when the VRSEL retention method is used.
During pre-ACS processing, use the EDG_EXIT100 installation exit to obtain information that is used by the ACS routines. The EDG_EXIT100 installation exit can provide a vital record specification management value in the MSPOLICY read-only variable, which is used by the ACS routines. During pre-ACS processing, DFSMSrmm does not make the RMMVRS environment call to the ACS routine. This method applies to both the EXPDT and VRSEL retention methods.
You can set the EXPDT in one of these ways:
- Specify RETPD or EXPDT at allocation time or in the JCL
- Use data class
- Use the EDG_EXIT100 installation exit
- Use the DFSMSrmm default retention - EDGRMMxx parmlib OPTION RETPD
- Use the DFSMSrmm ADD and CHANGE command for EXPDT and RETPD
- From the TCDB tape volume record (VOLCAT)
- Use the SMS management class expiration attribute 'Expire after Date/Days' (must be enabled by the EDGRMMxx parmlib option MCATTR)
- Use the LASTREF data set attribute (only for volumes managed by the EXPDT retention method). LASTREF can be set by:
  - the SMS management class expiration attribute 'Expire after Days Non-usage'
  - the default EDGRMMxx parmlib OPTION RM(EXPDT(LASTREF(value)))
  - a DFSMSrmm ADDDATASET or CHANGEDATASET LASTREF command.
DFSMSrmm records how the EXPDT and retention method are set.

Using SMS ACS processing you can have an automatism to set the expiration date and LASTREF extra days of a data set from the management class expiration attributes 'Expire after Date/Days' and 'Expire after Days Non-usage'. You can tailor the usage of the management class attributes by DFSMSrmm with the EDGRMMxx parmlib option MCATTR.

Using SMS ACS processing you can consolidate policy assignment decisions in a single place whether you use system-managed tape or not. You can use SMS ACS routines to assign management class for your data sets instead of using vital record specification management values assigned by the EDG_EXIT100 exit. You can assign a management policy by name to either a non-system-managed or a system-managed tape data set. If the use of the management class attributes is enabled by the EDGRMMxx parmlib OPTION MCATTR, you can use the management class Expiration Attributes ('Expire after Date/Days' and 'Expire after Days Non-usage') to set the data set EXPDT and LASTREF attributes, where appropriate.

For non-system-managed tape, DFSMSrmm calls the ACS routines to obtain a management class. The management class is used in place of the vital record specification management value assigned by the EDG_EXIT100 installation exit. When a management class name is assigned using ACS routines, the EDG_EXIT100 installation exit is not called for a vital record specification management value. The decision to call the EDG_EXIT100 installation exit is made each time a new data set is created on a tape based on whether a construct is assigned by ACS processing. You have the flexibility to identify one request to be handled by ACS and the next request to be handled by the EDG_EXIT100 installation exit. For compatibility, DFSMSrmm passes the vital record specification management value that is determined by the EDG_EXIT100 installation exit by using the pre-ACS interface in the MSPOLICY variable. You might use the vital record specification management value in the MSPOLICY variable as the base for MC assignment for system-managed tape. Even when you use SMS ACS support to assign management class names you can have separate policies for retention and movement by using a primary data set name vital record specification and a secondary management class vital record specification.

Use the ACS routine to assign the management class as the secondary vital record specification and the DFSMSrmm data set name vital record specification to assign the primary vital record specification.

You can still use the EDG_EXIT100 installation exit to check for either EXPDT= or ACCODE= specifying special values and override them to ensure correct retention processing by DFSMSrmm.