CA Dynam for VSE User Guide

DYNCAT Commands
VTOC Command
Use the VTOC command to create and delete the VTOC indexes used by the
CA Dynam/D VTOC Management. Each VTOC index is a small disk file
containing an index to the entries in the unmodified VTOC for the device.
These files have a standard name of 'DYNAM.VTOC.INDEX'.
The format of the command is shown below.
VTOC
{INITIAL|DELETE } VOLser=xxxxxx
INITIAL
DELETE
Creates the VTOC indexes used by CA Dynam/D VTOC Management.
Deletes the VTOC indexes used by CA Dynam/D VTOC Management.
Note: INITIAL and DELETE are mutually exclusive; one is required.
VOLser=
BLDIX
Required parameter. Indicates the DASD device upon which the VTOC index is
to built or from which the VTOC index is to be removed. Valid entry is a 1- to
6-character volume serial number.
Builds the VTOC index used by CA Dynam/D VTOC management.
Using the VTOC INITIAL Function
For performance reasons, we recommend that the VTOC index be located as
near to the VTOC of the volume as possible, ideally on the same cylinder with
the VTOC, immediately preceding it. As a general guideline, the VTOC index
file should be the same size (number of tracks) as the VTOC on CKD devices,
and twice the size (twice the number of blocks) as the VTOC on FBA devices.
The minimum size for the VTOC index is two tracks on CKD and 80 blocks on
FBA. The minimum size for the VTOC index is four tracks if the CKD device has
more than 32K cylinders.
Using the VTOC DELETE Function
The DELETE function disables CA Dynam-indexed VTOC support for the volume
and removes the index file.
Using the VTOC BLDIX Function
The BLDIX function will rebuild a VTOC index on a particular volume. This
function can only be run if a VTOC index exists on the volume prior to running
the BLDIX function. BLDIX is useful because expired files are deleted. This
function is not mandatory because indexes are automatically rebuilt. For more
information, see Deleting Expired Files in the chapter “Disk File Management.”
Chapter 8: Maintaining the Catalog−DYNCAT Program 8–93