Setting Up ELIB Data Sets › How to Allocate and Initialize an ELIB Data Set › How to Allocate and Initialize the Data Set › Allocate and Initialize a VSAM ELIB Data Set

Allocate and Initialize a VSAM ELIB Data Set

Note: The ELIB data set format supports z/OS VSAM extended addressability for VSAM data sets. The extended addressability feature lets you allocate VSAM data sets that are larger than 4 gigabytes. If extended addressability is enabled in z/OS for any of your VSAM ELIB data sets, CA Endevor SCM recognizes that this option is enabled and handles ELIB access appropriately. You do not need to make any changes in CA Endevor SCM to enable support for extended addressability. Ask your Storage Administrator to determine whether z/OS VSAM extended addressability is available for your site and how you can implement it.

To allocate a VSAM cluster, use the IBM IDCAMS utility in a JCL stream similar to the following:

//ALOCVSAM EXEC PGM=IDCAMS
//SYSPRINT DD SYSOUT=*
//SYSIN   DD *
 DEFINE CLUSTER -
     (NAME(VSAM.DATASET) -
     MASTERPW(plant) -
     CONTROLPW(ENDEVOR) -
     UPDATEPW(ENDEVOR) -
     RECORDSIZE(4088 4088) -
     CONTROLINTERVALSIZE(4096) -
     SHAREOPTIONS(3,3) -
     VOLUMES(BST001) -
     CYLINDERS(5,2) -
     NONINDEXED  -
     )  -
  DATA (NAME(VSAM.DATASET.DATA)  -
     MASTERPW(plant)  -
     CONTROLPW(ENDEVOR)  -
     UPDATEPW(ENDEVOR)  -
     )

In this example, the IDCAMS utility will define a VSAM cluster named VSAM.DATASET. The control interval for this data set will be 4096 bytes, and the record size will be 4088 bytes. In VSAM data sets the record size is the same as the page size. IDCAMS will allocate 5 cylinders of primary storage, and 2 cylinders to secondary storage for the data set. The data set will reside in a DASD volume with a serial number of BST001. The master password to the data set will be plant.

Note: Choose a master password to protect your data. This password is required whenever you want to delete or rename the cluster. CA Endevor SCM processing uses the built-in password ENDEVOR for all update processing. If you omit the master password, this library will be unprotected.

Before initializing this data set as an ELIB data set you need to convert your estimated space requirements to their page equivalents. This is necessary because the BC1PNLIB utility needs all its specifications in pages.

In VSAM data sets the page size is eight bytes smaller than the control interval size, in this case 4088 bytes. The number of 4088 byte pages per track and per cylinder will vary by DASD device, as shown in the following table:

The VSAM data set in this example would therefore have a capacity of 750 pages in primary storage and 300 pages in secondary storage when using a 3380 device, and 900 pages in primary storage and 360 pages in secondary storage when using a 3390 device.

Note: If you are using VSAM, specify one less page than will fit in the primary space allocation. VSAM uses one control interval for an end-of-file mark. For example, on a 3380 device with one cylinder of primary space allocation you should specify 149 pages per cylinder.

Use the BC1PNLIB utility to initialize the data set. The following JCL assumes that you are using a 3380 device.

//ELIBINIT EXEC PGM=BC1PNLIB
//STEPLIB  DD DISP=SHR,DSN=iprfx.iqual.CSIQAUTU
//     DD DISP=SHR,DSN=iprfx.iqual.CSIQLOAD

//*
//*
//*
//INITVSAM  DD
//   DSN=VSAM.DATASET,DISP=(OLD,KEEP)
//SYSPRINT DD SYSOUT=*
//BSTERR  DD SYSOUT=*
//SYSUDUMP DD SYSOUT=*
//SYSIN   DD *
 INIT   DDNAME = INITVSAM
      PAGE SIZE = 4088
      ALLOCATE = (749,300)
      RESERVE PAGES = 150
      DIRECTORY PAGES = 14
.
INQUIRE  DDNAME = INITVSAM
 .
/*

In this example, you have allocated and initialized a VSAM data set as an ELIB data set with 749 pages initialized as primary storage. When 150 pages remain in this primary storage area, CA Endevor SCM automatically attempts to allocate and initialize secondary storage with a capacity of 300 pages. In addition you have requested the BC1PNLIB utility to list statistical information about this data set after it has been initialized.