DASD CONFIG File

Contents
vmx32besp
Contents
The DASD CONFIG file can contain the following six types of records that are used to define the configuration the
VM:Secure
will manage:
  • DEVTYPE
  • EXTENT
  • IGNORE
  • NOLINK
  • SUBPOOL
  • VOLUME
As part of installation, the DASD CONFIG file is created for you and resides on the
VM:Secure
A - disk.
To make changes to any of the records in this file, use the CONFIG command with the DASD parameter. All changes take effect immediately. You cannot use these records in any other configuration file.
DASD CONFIG File Records
The following table shows the sequence requirements of the records that appear in the DASD CONFIG file. For a sample DASD CONFIG file, see Sample DASD CONFIG.
Record
Sequence Requirements
Quantity Allowed
SUBPOOL
Must appear before the specified subpool is referenced by an EXTENT record
Multiple
DEVTYPE
Must appear before the specified device is referenced by a VOLUME record
Multiple
VOLUME
Does not require that an EXTENT record follow it. When one does not, all space on the entire volume is treated as not controlled by
VM:Secure
; the volume itself is controlled
Multiple
EXTENT
Must appear immediately following the VOLUME record to which it applies, or following other EXTENT records for the same volume
Multiple
IGNORE
Can appear anywhere in the file
Multiple
NOLINK
Can appear anywhere in the file
Multiple
You can manage DASD through
VM:Secure
if you identify the DASD to
VM:Secure
in its DASD CONFIG file.
Sample DASD CONFIG File
The following sample DASD CONFIG illustrates the statement use.
* SUBPOOL MAIN ROTATING LOWEND * *  VOLUME VMPK01 9336  EXTENT 0 15 * ALLOCATION  EXTENT 16 122199 MAIN  EXTENT 122200 126015 * SPOOL SPACE  EXTENT 126016 557999 MAIN  VOLUME VMPK02 3390  EXTENT 1 3338 MAIN * IGNORE $ALLOC$ * NOLINK MAINT 190 NOLINK MAINT 19E
Record
Purpose
SUBPOOL MAIN ROTATING 
LOWEND *
Defines one subpool, MAIN, with ROTATING LOWEND as the allocation procedure for MAIN, and no maximum size for allocation requests (designated by the asterisk).
VM:Secure
uses the volumes in the reverse order from the way they are defined in the DASD CONFIG file. It allocates the first minidisk on VMPK02 and begins at the low end of an available extent. It allocates the second minidisk on VMPK01 and begins at the low end of an available extent.
VOLUME VMPK01 9336
Defines a 9336 DASD with a volume label of VMPK01.
EXTENT 0 15 * ALLOCATION
EXTENT 16 122199 MAIN
EXTENT 122200 126015 * SPOOL SPACE
EXTENT 126016 557999 MAIN
Define four extents for volume VMPK01. The first and third extents are fixed CP extents (indicated by the asterisk), and are used for allocation and spool space, respectively (indicated by the comments following the asterisks). The second and fourth extents are available for minidisk allocations and are assigned to the allocation definitions set up for subpool MAIN.
VOLUME VMPK02 3390
Defines a 3390 DASD with a volume label of VMPK02.
EXTENT 1 3338 MAIN
Defines one extent for volume VMPK02. This extent is available for minidisk allocations and is assigned to the allocation definitions set up for subpool MAIN.
IGNORE $ALLOC$
Specifies minidisks to ignore during overlay checking.
NOLINK MAINT 190
NOLINK MAINT 19E
Identifies directory links not to be mapped.
Effects of Changing Records in the DASD CONFIG File
Although you can dynamically change all values on all DASD CONFIG file records, there are certain restrictions and expectations that are established for each record type.
  • DEVTYPE Records
    You can add, change, and delete DEVTYPE records without restrictions. Any new values are used in all subsequent references.
  • EXTENT Records
    You can add EXTENT records without restrictions.
    You can delete EXTENT records, but all minidisks defined within those extents will no longer be controlled by
    VM:Secure
    .
    When changing the cylinder or block ranges, existing minidisks cannot cross the boundary between two extents and must be either completely within a single extent or completely outside all extents. If you do not follow these guidelines, the extent information will not be updated. Additionally, any minidisks that were previously contained within a defined extent and are not within any extent after the update will no longer be controlled by
    VM:Secure
    .
    You can change the subpools listed on an EXTENT record as long as the subpools are still defined. If you change an allocatable extent with subpools to a fixed CP extent, you must use IGNORE records to make all minidisks in that extent ignored to avoid overlay conflicts that will prevent the update from completing.
  • IGNORE Records
    You can add, change, and delete IGNORE records without restrictions, unless removing an IGNORE statement will cause an overlap.
  • NOLINK Records
    You can add, change, and delete NOLINK records without restrictions. However, if you change or delete a NOLINK record so that fewer minidisks are removed from LINK mapping, then
    VM:Secure
    must scan the entire object directory to recreate the LINK mapping structure.
  • VOLUME Records
    You can add VOLUME records without restrictions.
    You can delete VOLUME records, but all minidisks defined on those volumes will no longer be controlled by
    VM:Secure
    .
    You can change the device type name on a VOLUME record as long as the true underlying device type does not change. For example, assume you have a DEVTYPE record that defines a custom device type, 3390NMDC, based on a 3390 prototype, and a VOLUME record that specifies the 3390NMDC name. You can change the device type name to 3390 or any other name that also resolves to a true 3390 device type.
  • SUBPOOL Records
    SUBPOOL records can be added without restrictions.
    You can delete SUBPOOL records as long as the subpools being deleted are not referred to on any EXTENT records.
    You can change SUBPOOL records without restrictions. The new values will be used for all subsequent allocations from that subpool.