INITIALIZE (Initialize Disk)

The INITIALIZE (Initialize Disk) command initializes variable-sector-size disks that were preformatted by the manufacturer or that were previously configured with the RC (Reconfigure Disk) command.

A locking mechanism prevents multiple copies of programs from attempting to use the ACQUIRE (Acquire Resource), CLOSE (Close Pack), FREE (Free Resource), INITIALIZE (Initialize Disk), LB (Relabel Pack), PG (Purge), PG (Purge), and UR (Unit Reserved) commands to access the same device simultaneously. If one of these operations is already in progress when another command is issued to the same device, the command is rejected and the following message is displayed: 

PK <unit> <command entered> COMMAND REJECTED BECAUSE
    ANOTHER COMMAND IS USING THIS UNIT.

If the command is rejected, wait for the current command to complete and enter the command again.

Syntax

<oldname list>

<sector format>

NATIVE, VSS1, VSS2, or VSS3.

Explanation

This command

  • Applies a Unisys label to the disks.

  • Writes a master available table (MAT) on the disks.

  • Initializes the disks to a capacity based on the physical capacity of the device and MCP environment capacity calculation algorithms.

After the INITIALIZE command completes, you can perform one of the following actions:

  • Mark the disks as scratch disks with the PG (Purge) command.

  • Use the RC (Reconfigure Disk) command to create new disk families, add them as continuation packs to existing disk families, or create them as SPARE mirror disks.

Note: You can avoid using the INITIALIZE system command altogether by including the INIT VSS option in the PG (Purge) or RC (Reconfigure Disk) commands.

VSS = <sector format>

Controls the sector format used for the disk units being initialized. For more information about VSS sector formats, refer to the Peripherals Information File and the Disk and Tape Storage Systems Configuration Guide for your system.

You must specify the VSS format for the command to be executed.

Possible values for <sector format> are:

  • NATIVE

    NATIVE is valid only for emulated disk units (also known as logical disks). How MCP logical sectors are mapped and accessed depends on the setting of the SYSOPS option IOPBYPASWICACHE. For more information, refer to the SYSOPS (System Options) command and to the Disk and Tape Storage Systems Configuration Guide for your system.

  • VSS1

    VSS1 initializes a 512-byte/sector MCP physical disk unit to the VSS1 format. This format enables the maximum amount of data to be stored on disk, but might slow performance for some applications relative to the same disk initialized as VSS2.

    Note: Note: The value of GAPS (which determines whether adjacent file rows are allowed to share a physical disk sector) is set to FALSE for this command. The value of GAPS can be modified using the RC (Reconfigure Disk) command.

  • VSS2

    VSS2 is valid for both 512-byte/sector MCP physical disk units, and all emulated disk units. It maps two logical, 180-byte sectors onto each physical 512-byte disk sector. This format enables system software and applications designed for 180-byte sector disks to efficiently use industry-standard, 512-byte/sector disks.

  • VSS3

    VSS3 is valid for both 4096-byte/sector MCP physical disk units, and emulated disk units. It maps 22 logical, 180-byte sectors onto each physical 4096-byte disk sector. This format enables system software and applications designed for 180-byte/sector disks to efficiently use industry-standard, 4096-byte/sector disks.

OLDNAME = <oldname list>

For disks previously labeled by the RC (Reconfigure Disk) command, you can specify the current family names of the disks that are to be initialized. Otherwise, you must respond to an ACCEPT OLDNAME = <FAMILY NAME> request for each disk. Note that the order of the family names in the oldname list does not matter.

Examples

Example 1

This example initializes disk 43 to VSS-2 format: 

INIT PK 43 VSS = VSS2

Example 2

This example initializes disks 80, 81, and 836 to VSS-2 format. Disks 80 and 81 were already named TEST, and disk 836 was already named ALPHA. 

INIT PK 80 - 81, 836 OLDNAME = (ALPHA, TEXT) VSS = VSS2

Considerations for Use

This command can be used only if all the following conditions are true:

  • The I/O subsystem supports variable sector size disks.

  • The disk units are self identifying disks with variable sector size, or emulated disk units (also referred to as logical disks).

  • The disk units are write-enabled but are not in use.

  • If the disk units are mirrored disks, they must be closed.

To initialize a mirrored disk, you must first release the mirrored disk with the MIRROR RELEASE command. The INITIALIZE command is allowed for closed mirrored disks and disks assigned to the spare disk pool for the mirrored disk pool facility (MDPF).

Following are messages that can be displayed in response to this command: 

PK <unit number> INITIALIZED TO <180-byte-sectors>
   SECTORS (<total-bytes> BYTES)

The disk was successfully initialized.

PK <unit number> CANNOT INITIALIZE A MIRRORED UNIT

An attempt was made to initialize a member of a mirrored set. You must release the mirrored disk with the MIRROR RELEASE command before the disk can be initialized. 

PK <unit number> HAS BEEN INITIALIZED TO THE MAXIMUM
    SUPPORTED CAPACITY

The capacity of the disk being initialized exceeds the maximum disk capacity supported by the MCP. The disk will be initialized to the maximum capacity supported by the MCP. 

PK <unit number> INVALID CAPACITY - DISK CANNOT BE INITIALIZED

The disk capacity is less than 64 megabytes, which is the minimum capacity required for a self-identifying disk with variable sector size.

Prev  Up  Next
IL (Ignore Label)  Home  INSTALL (Install Software)