Step 1: Preparatory steps for OAE

Before running OAE, you must perform the preparatory steps.

About this task

The steps you take depend on whether you want to extend the IOVF or the SDEP portion of the area.

For details about extending the IOVF and the SDEP portions of the area, see Considerations on area extension.

Important: Step 1 through Step 5 are for allocating a larger data set, which is required only for the shadow expansion. If you specify the ROOT parameter in the SYSIN DD, skip Step 3 through Step 5. If you have decided to use the original expansion, start from Step 6.

Procedure

  1. Define a new data set.
    The data set is defined by the VSAM definition. The size of the CI must be identical to that defined for the other data sets of the same area. If the allocated space for the data set is not equal to or greater than that defined for the other data sets of the same area, the OAE utility will determine this and will end abnormally.
  2. The new ADS must be registered with DBRC.
    Use the DBRC INIT.ADS command with the UNAVAIL parameter to register the new ADS with DBRC. This command can be issued by one of the following ways:
    • Use of the Database Recovery Control Utility (DSPURX00) in batch
    • Use of the /RMINIT IMS command

    Related reading: For information about the INIT.ADS command, the DSPURX00 utility, and the /RMINIT command, see IMS Commands for the version of IMS that you are using.

  3. (For IOVF extension only) Change the ROOT parameter in the database descriptors (DBDs) in the DBDLIB for the area(s) to be extended.
  4. (For IOVF extension only) Run DBDGEN.
  5. (For IOVF extension only) Run ACBGEN.
  6. If necessary, run the SDEP SCAN/DLET utilities.

    The SDEP SCAN/DLET utilities are used to delete all of the SDEP segments with RBAs within the Cannibalized SDEP CIs (CSC) portion. The CSC for an area are those SDEP CIs which lie between the current first SDEP RBA and the new first SDEP RBA created as a result of IOVF extension, as shown in the following figure.

    Figure 1. CSC portion that is created as a result of IOVF extension
    This figure shows how the CSC portion is created after the extension by OAE. Detail of the CSC portion is described in this topic.
    If SDEP segments exist in the CSC portion, you must run the SDEP SCAN/DLET utilities before extending the area with OAE.
    Note: You do not need to run the SDEP SCAN/DLET utilities when you want to extend the IOVF portion of the area that has no SDEP segments in the CSC portion or has no SDEP definition in DBD, or when you want to extend only the SDEP portion.

    To check if SDEP segments with RBAs exist within the CSC portion, follow these steps:

    1. Run OPC or ODM to obtain the current SDEP LB and LE values.

      An SDEP LB value that is larger than the SDEP LE value indicates that SDEP segments with RBAs exist within the CSC portion. If the SDEP LB value is smaller than the SDEP LE value, continue with the next step.

    2. Calculate the first SDEP RBA (that is, the first SDEP RBA value after the extension) from the UOW and the ROOT parameters.
    3. A calculated first SDEP RBA value that is larger than the current SDEP LB value indicates that SDEP segments with RBAs exist within the CSC portion. Otherwise, SDEP segments with RBAs do not exist in the CSC portion.

    Related reading: For a JCL example to extend IOVF portion of an area that has SDEP segments, see Example 6: Extending the IOVF portion of the area that has SDEP segments.

  7. Issue the /VUNLOAD IMS command to remove the area from VSO (If applicable).
    Note that the current area must be removed from Virtual Storage Option (VSO) before running OAE.

    Related reading: For information about the /VUNLOAD command, see IMS Commands for the version of IMS that you are using.