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Numeric

Specifies the CSR address. This address must be a valid QBUS 22-bit address in IO space.

Initially its value is 017772150, which is the factory setting for the RQDX3 disk controller.

Use the "address" parameter for loading several instances of RQDX3. The "address" parameter value must be unique for every instance of the controller.

max_n_of_units

Specifies the maximum number of units supported by the controller. Possible values are 4…9999.

The default value is 9999.

container[N]

N=0…9999

Specifies the location of the disk container. It can be either the name of a ".vdisk" file or the name of a physical disk:

• local fixed disks (IDE, SCSI, SATA)
  • "\\.\PhysicalDrive<N>"

  • "\\.\PhysicalDrive(DevID =XXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX)"
    DevID addresses the target physical disk by its WWID
    (hexadecimal 128-bit identifier assigned to the disk
    drive by its manufacturer/originator).

    Example:

    set DUA container[3]="\\.\PhysicalDrive(DevID= 6008-05F3-0005-2950-BF8E-0B86-A0C7-0001)"

    .

• iSCSI disks
  • "\\.\PhysicalDrive(iScsiTarget = <iSCSI target>, LUN = <LUN number>)"
    

    iScsiTarget addresses the disk by its iSCSI target name.
    LUN specifies LUN on connected iSCSI disk. 

    Example:

    set DUA container[0]="\\.\PhysicalDrive(iScsiTarget= iqn.2008-04:iscsi.charon-target-test1, LUN= 1)"

    .

• floppy drives
  • "\\.\A:"
  • "\\.\B:"
    .
• CD-ROM, DVD drives (IDE, SCSI, …)
  • "\\.\CdRom<N>"

media_type[N]

N=0…9999

Text String

Overrides the default (automatically determined) MSCP media type of a device.

Syntax:

where:

• <device-name> is one of “DU”, “DK”, “SCSI”, “DI”, “DSSI”, “DJ”

• <device-type> is of the form “LLD” or “LLLD”, where “L” is a letter from A through Z, and “D” is a decimal number from 0 through 99

If not specified, the device name is set to “DU” and the device type is selected based on disk size.

Initially not specified.

geometry[N]

N=0…9999

Text String

This formatted string value specifies the explicit geometry of the disk storage element with a DSSI node id: N and an MSCP unit number: N. This parameter is not applicable to tape storage elements.

The string format is <X>”/”<Y>[“/”<Z>] where:

If this parameter is not set, CHARON-VAX / CHARON-PDP will configure the geometry based on the most probable disk type.

use_io_file_buffering[N]

N=0…9999

Text String

Instructs CHARON-VAX to enable host operating system I/O cache on reading/writing operations.

The following values are possible:

• "true" or "write-back" - the "write back" caching mode is used

• "write-through" - the "write through" caching mode is used

• "false" - caching is switched off

 Note that this caching has a significant effect only in case of mapping to disk and tape containers, not physical drives.

When enabled, host operating system I/O cache may significantly improve I/O performance of the virtual system. At the same time maintaining I/O cache requires additional host resources (CPU and memory) which may negatively affect overall performance of the virtual system.

Initially is set to "false".

Example: