Creating and formatting Log and History File data sets

This section describes the procedures for creating and formatting the Log and History File data sets.

The Log and the History File are key components of DELTA PLUS and DELTA PLUS VIRTUAL TERMINAL. Both the Log and the History File are pairs of formatted BSAM data sets that record all product updates to a control region. Dual data sets are maintained for both the Log and the History File for recovery and reliability reasons, since both are integral to product operation. Both the dual Log data sets and the dual History File data sets must be available before any updates can be made to the control region. Only one Log data set and one History File data set is necessary for the Log and History File utilities to function.

The IMS control region must have UPDATE authority for the Log and History File data sets.

Note

During IMS control region initialization, the IMS DB/DC SYSGEN linkedit dates are written to the Log and History File control record (if required). The Log and History File SYSGEN dates are also updated following an online change MODBLKS GEN implementation.

To create and format the Log data set

Warning

Log format processing deletes all Log entries. After this is done, an IMS warm start (/NRE without CHKPT 0) or emergency restart (/ERE) is not possible. Therefore, you must cold start IMS after formatting the Log data sets, which will cause all restart information in the Log data sets to be lost.

  1. Invoke the online interface through the modified ISPF/PDF Primary Option Menu that you created in Accessing-the-products-from-an-ISPF-options-menu or through the CLIST that you created in Accessing-the-products-from-a-CLIST.The Main Menu is displayed.
  2. Type 3 in the selection field and press Enter.The Utilities Menu is displayed.
  3. Type 1 in the selection field and press Enter.The Log Maintenance Menu is displayed.
  4. Type 4 in the Log Maintenance Option selection field.
  5. Type the name of the target IMSID or IMS data-sharing group in the IMSID or Group field and press Enter.The Allocate New Log Data Set panel is displayed.
  6. Enter the information for the fields that are available on the Allocate New Log Data Set panel for the primary Log data set and press Enter.The primary Log data set is allocated.
  7. Enter the information for the fields that are available on the Allocate New Log Data Set panel for the secondary Log data set and press Enter.The secondary Log data set is allocated and the Confirm Log Format panel is displayed.
  8. Type 1 in the selection field and press Enter to complete creating and formatting the Log data sets.

To create and format the History File data set

Warning

If you reformat an existing History File data set, you destroy the data set contents. You will lose all audit information concerning any changes that have been made to the control regions that are associated with the History File.

  1. Invoke the online interface through the modified ISPF/PDF Primary Option Menu that you created in Accessing-the-products-from-an-ISPF-options-menu or through the CLIST that you created in Accessing-the-products-from-a-CLIST.The Main Menu is displayed.
  2. Type 3 in the selection field and press Enter.The Utilities Menu is displayed.
  3. Type 2 in the selection field and press Enter.The History File Maintenance Menu is displayed.
  4. Type 4 in the History File Maintenance Option selection field.
  5. Type the name of the target IMSID or IMS data-sharing group in the IMSID or Group field and press Enter.The Allocate New History File Data Set panel is displayed.
  6. Enter the information for the fields that are available on the Allocate New History File Data Set panel for the primary History File data set and press Enter.The primary History File data set is allocated.
  7. Enter the information for the fields that are available on the Allocate New History File Data Set panel for the secondary History File data set and press Enter.The secondary History File data set is allocated and the Confirm History File Format panel is displayed.
  8. Type 1 in the selection field and press Enter to complete creating and formatting the History File data sets.

 

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