Space announcement This space provides the same content as before, but the organization of the home page has changed. The content is now organized based on logical branches instead of legacy book titles. We hope that the new structure will help you quickly find the content that you need.

Allocating the primary shadow area data set

If you elect to dynamically allocate the primary shadow area data set for the SHADOW_INIT command, you can specify unique allocation characteristics for the areas by using the ALLOCATE subcommand and its related keywords. The ALLOCATE subcommand can be used as a replacement for DELETE, DEFINE, and other statements that are normally specified by executing the Access Method Services IDCAMS program.

Note

If the IDCAMS program is already defined in your job input, it is not necessary to remove it. However, any defining statements that are specified under IDCAMS for the area are superseded by similar parameters that are specified on the ALLOCATE subcommand.

The following functions are defined by specifying combinations of keywords that are specified on the ALLOCATE subcommand:

  • Delete/define, reuse, or rename the VSAM cluster that is used for the areas
  • Specify the number of volumes and allocation units for the areas
  • Pass optional parameters to Access Method Services for the VSAM cluster definition
  • Specify the SMS storage class, management class, and data class for the areas
  • Specify space requirements for the areas
  • Specify volume serial identifiers for the areas

Identifying the areas for ALLOCATE processing

The OAREA keyword identifies the areas (by area name or by area number) that apply to the ALLOCATE subcommand.

Each area that is referenced must appear in the Restructure Plan data set as selected for restructure processing. You can reference any area that is defined in the database, whether or not it has been selected to be restructured. If you reference an area that has not been selected, it is ignored and has no effect on restructure processing.

In addition, you can specify the same area on multiple ALLOCATE subcommands; however, the SHADOW_INIT command uses the first ALLOCATE subcommand that references the area. If an area is not specified in any ALLOCATE subcommand, you must define the cluster manually before executing the SHADOW_INIT command.

Allocating the area data set characteristics

You can specify the IDCAMS_OPTION keyword on the ALLOCATE subcommand to pass optional parameters to Access Method Services for the VSAM cluster definition.

Numerous parameters are available for use with this keyword to control the values that are used by AMS for the VSAM cluster definition. For more information, see the IBM Access Method Services Reference Manual.

Other keywords are available that let you specify the SMS class, space requirements, and volume serial identifier for the area. These keywords function in the same manner as on other Fast Path/EP subcommands. The following keywords are available:

  • AVGREC
  • DATACLAS
  • MGMTCLAS
  • SPACE
  • STORCLAS

For more information about the keywords that are available with the ALLOCATE subcommand, seeALLOCATE documentation.

Related topic

Initializing-shadow-area-data-sets


 

Tip: For faster searching, add an asterisk to the end of your partial query. Example: cert*