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Create Bootable Optical Media (CD, DVD)?

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The Question is:

I have created a min install disk from AXPVMS$PCSI_INSTALL_MIN.COM for use on a
 DS20E VMS 7.2-1 system (as per 1075 ask the wizard).  When booting from a
 "normal" disk everything is fine.  When an image of that same disk is backed
 up into an LD disk and b
urned as a CD-ROM, the following error occurs during boot and the system is hung:
"%SYSTEM-I-MOUNTVER SABKUP$DQA0: has been write-locked.  Mount verification in
It seems obvious that the CD version is write locked - what can/should be done
 to circumvent (as you have suggested this CD method in the past as a viable
 stand-alone boot method?)

The Answer is :

          OpenVMS System Disks and CD and DVD Recording
                    Copyright 1976, 2004 Hewlett-Packard Development
                   Company, L.P.
                   Neither HP nor any of its subsidiaries shall be
                   liable for technical or editorial errors or
                   omissions contained herein.   The information
                   in this document is provided "as is" without
                   warranty of any kind and is subject to change
                   without notice.   The warranties for HP products
                   are set forth in the express limited warranty
                   statements accompanying such products.   Nothing
                   herein should be construed as constituting an
                   additional warranty.
                               Document Abstract
                   This document describes CD and DVD recording, and
                   ways to generate bootable media for use with the
                   OpenVMS Alpha and OpenVMS I64 operating systems.
                   This document does not discuss specific recording
                   tools, though a recording tool is assumed available
                   and is required when recording optical media.
                   There are presently no DVD recording devices that
                   have native support within OpenVMS.  There are
                   recording packages for OpenVMS, please see the
                   OpenVMS Frequently Asked Questions (FAQ) for
                   related materials and recording information.
                   No information contained here should be construed
                   as a statement of support by HP.
          1.1  CD and DVD Technology Introduction
                   The two core technology platforms are Compact Disk
                   (CD) and Digital Versatile Disk (DVD), and there are
                   various formulations of each of these technologies.
                   This section will provide a general overview of the
          1.1.1  Compact Disk (CD) Technologies
                   CD was first available as a pressed media, known as
                   CD-ROM. The recording medium of CD-ROM is physically
                   pressed into a series of pits, encoding the desired
                   data onto the medium. A red laser is then used to read
                   the signals produced by reflections from the patterns
                   of pits.
                   CD then evolved into recordable technologies, including
                   a write-once technology known as CD-R and a rewritable
                   format known as CD-RW. These differed from classic CD-
                   ROM as they are produced by writing a pattern onto
                   a photochemical layer on special disks, typically
                   using the same laser used to read the disk, albiet
                   at higher power. The results of the recording process
                   are intended to optically duplicate the appearance of
                   pressed media.
                   Recording typically starts at the inside of the disk
                   nearest the hub, and spirals outward toward the edge of
                   the optical medium.
                   Older CD-ROM drives may not be able to read CD-R or
                   CD-RW media.
                   Capacities on CD media are sometimes given in bytes and
                   sometimes in minutes. The former assumes data, and the
                   latter assumes audio storage.
                   Each CD disk can hold upwards of 600 or 700 megabytes
                   and potentially more, depending on the particular
                   drive and the particular recording medium. CDs
                   with capacities of 600 megabytes are recordable and
                   transportable across the widest variety of devices,
                   though 700 MB is also widely compatible.
                   Reading and writing of CD media occurs at pre-set
                   speeds, with the original and classic recording speed
                   of 150 kilobytes per second and subsequently known as
                   1X CD recording. Drives are commonly available that
                   record at speeds far faster than this, with the three
                   broad ranges of recording speed being broken down into
                   the original and classic speed range, the High Speed
                   range (4X to 24X), and the Ultra-Speed range (10X and
                   Most current drives now operate at variable speeds,
                   depending on various factors including as the position
                   of the data on the disk and even potentially on
                   the error rates detected as the medium is read. The
                   drive peak speeds are usually cited in the marketing
                   materials, and the actual speeds can be lower.
                   The central factor in a successful CD recording process
                   involves choosing a speed that is supported by the
                   particular medium in use, by the drive, and by the host
                   system. Faster recording requires the photochemical
                   change to occur sufficiently quickly when each pit
                   is written, and support in the drive itself for the
                   particular recording speed, and the ability of the
                   host to stream data out to the device. Additional
                   information on recording speeds is available in
                   Section 1.1.5.
                   There are other CD recording formats and variants,
                   though these other variants are now in comparatively
                   limited or otherwise specialized use.
                   The majority of recent CD devices on IDE/ATAPI, SCSI
                   and USB buses support the Multimedia Commands (MMC)
                   command interface.
          1.1.2  Digital Versatile Disk (DVD) Technologies
                   Like CD, DVD was first available as a pressed media,
                   known as DVD-ROM. Like CD, a red laser is then used to
                   read the signals produced by the reflections from the
                   patterns of pits.
                   DVD then evolved into multiple recordable technologies,
                   including three general families of recording
                   technologies. Like CD, both write-once and rewritable
                   formats are available. Unlike CD, there are variants
                   of each. The write-once formats are known as DVD-R and
                   DVD+R, and the rewritable formats as DVD-RW, DVD+RW,
                   and DVD-RAM.
                   DVD-R and DVD-RW (collectively known here as DVD-R/RW)
                   use relatively similar command sets, while DVD+R and
                   DVD+RW (collectively DVD+R/RW) use a different command
                   set and provide slightly different capabilities.
                   DVD-R/RW initially targeted video recording, while
                   DVD+R/RW initially targeted the requirements of digital
                   data recording. The DVD-RAM format was targeted at
                   environments with somewhat higher read-write cycles[2].
                   Like CD-R/RW recording, the results of the recording
                   process are intended to optically duplicate the
                   appearance of pressed media.
                   Each of the formats requires specific and appropriate
                   recording media.
                   HP has traditionally targeted the DVD+R and DVD+RW
                   technologies, though current HP DVD drives support
                   DVD+R, DVD+RW, DVD-R and DVD-RW formats, as well as
                   DL (Double Layer, Dual Layer) recording capabilities.
                   Drives that support CD-R/RW, DVD-R/RW and DVD+R/RW
                   recording are now common in the market, and there
                   are drives which can additionally read and record the
                   DVD-RAM format.
                   Unlike CD recording, traditional DVD-ROM media can be
                   recorded in two layers, with adjustments made to the
                   focus of the laser used to read the pits of each layer.
                   This increases the recording capacity of one side of
                   the DVD medium from 4.7 GB to approximately 9.4 GB.
                   DVD Dual-Layer (DL) recording is a relatively recent
                   innovation, and allows recording two layers of data on
                   a single side of the recording medium.
                   Newer technologies target the use of a blue laser
                   to read and write data, allowing for much higher
                   Paralleling CD-R/RW recording, older DVD-ROM drives may
                   not be able to read recorded DVD media, and there can
                   be incompatibilities seen across various combinations
                   of drives, drive types and media types. You will
                   want to test compatibility, you will want to ensure
                   current drive firmware, and you will want to ensure
                   the older drives are replaced. Newer media formats
                   and newer media recording speeds can require firmware
                   updates with older drives; in specific notable cases,
                   attempted use of newer media can damage or destroy
                   a down-revision drive, and can damage or destroy the
                   Various DVD drives can feature commodity-level hardware
                   pricing, and the entire drive is usually considered the
                   replaceable unit. Do expect to replace your DVD drive,
                   whether to move to a faster speed, to add new format
                   support, or to effect a repair.
                   Like CD recording, there are other DVD recording
                   formats and variants.
          1.1.3  Media Care and Handling
                   The recording substrate for all CD and DVD media is
                   generally located very close to the side of the disk
                   medium with the label, and comparatively far from what
                   is often considered to be the recording surface. The
                   recording layer can be physically or chemically damaged
                   by the label, by removal of the label, by the use of
                   ballpoint pen or similar marker, or even by the use of
                   specific and incompatible inks or dyes.
                   Environmental and physical factors such as mishandling,
                   thermal extremes, moisture, exposure to direct
                   sunlight, and scratches can also all lead to
                   accellerated media degradation and to media failure.
                   Rotational imbalances caused by defects in the medium
                   or by unbalanced or misapplied labels can also cause
                   serious problems, and potentially even catastrophic
                   Catastrophic failures can also potentially damage the
                   drive or the drive optics.
          1.1.4  Device Firmware and Device Damage
                   There are cases where drive firmware has been found
                   incompatible with (usually) newer media types or
                   newer media speeds, and this has led to compatibility
                   problems, to media failures, and occasionally even
                   to conditions that resulted in physical damage to the
                   recording drive.
                   Always ensure that the device firmware is the most
                   current available version, and that it is compatible
                   with the recording medium in use.
                   If you are moving to faster media or to newer formats,
                   always ensure the device in use is compatible with the
                   speed and the media, particularly with DVD media.
          1.1.5  Recording Media and Recording Speeds
                   CD-R/RW recording and rewriting is sensitive to the
                   recording speeds permitted by the drive and to the
                   maximum recording speed permitted by the recording
                   This tool defaults to the maximum CD-R/RW recording
                   speed permitted by the drive, and must assume that
                   the CD-R/RW recording medium loaded has a sufficient
                   speed rating for that default recording speed. It is
                   possible to exceed the rated CD recording speed or
                   to otherwise have inappropriate CD recording media
                   loaded, and this can and often will lead to recording
                   problems or recording failures. Most commonly, this
                   will result in write errors and in recording failures;
                   in incomplete, erroneous or partially recorded media.
                   Use of under-rated CD recording media is not
                   If you must use the lower-speed CD recording media,
                   the use of the /SPEED qualifier is often required for
                   successful completion of the recording process; you
                   may be required to select a recording speed below the
                   rated speed of the CD drive itself, and specifically
                   a recording speed that is compatible both with the CD
                   drive and with the CD recording media loaded in the
                   Unlike CD-R/RW, the permissible recording speed for
                   DVD+R/RW media is encoded directly onto the disk blank
                   when the media is manufactured, and this tool will
                   honor that speed. It is expected that a DVD+R/RW drive
                   loaded with lower-speed media will record at the lower
                   speed; at the speed appropriate for the media.
          1.2  General Preparation and Recording Instructions
                                         LD Assumed
                     This description assumes the use of LD.  Other
                     similar logical disk tools can also be used, as
                     can -- if your chosen recording tool supports
                     it -- an appropriately-sized physical disk
                     device.  An RZ29 series disk, for instance,
                     provides a capacity of 8,380,080 blocks, and
                     can thus potentially be used as a mastering
                     device for DVD recording operations.
                   Each time the OpenVMS Alpha system is bootstrapped,
                   start LD manually or in your SYS$MANAGER:SYSTARTUP_
                   VMS.COM procedure:
                     $ @SYS$STARTUP:LD$STARTUP.COM
                   Create and initially configure the LD logical disk file
                   (partition file). This step is needed only once:
                     $ ld create [/log] [/size=XXX] [/contiguous] filespec.dsk
                                          XFC and LD
                      There exist particular configuration requirements
                      with the combination of LD and the OpenVMS XFC
                      file cache. Please refer to Section 1.3.1 for
                      additional details and for the necessary cache-
                      related commands.
                      It is expected that this requirement will be
                      removed in a future release of LD and/or XFC.
                   With DVD+R and CD-R/RW media recording, the size of
                   the input determines the data recorded to the media.
                   In particular, you can select the media size to be
                   generated by correctly sizing the input data source.
                   With DVD+RW recording, the output device is always
                   the same size; it is always the maximum capacity of
                   the disk. On the classic Single-Layer (SL) DVD+RW
                   media, this is always 4.7GB. With HP DVD+RW media,
                   the observed size of such media is 9,180,416 blocks.
                   Accordingly, you will want to size your input
                   appropriately, or you will want to use the OpenVMS
                   Alpha V7.3-2 (and later) Dynamic Volume Expansion (DVE)
                   Enable the volume for DVE, and size the limit for at
                   least the 4.7 GB capacity of the DVD+RW target. Double-
                   Layer (DL) recording devices and media are expected to
                   require a larger limiting value, obviously.
                   Each time the system is bootstrapped, connect the LD
                   device to the target logical disk file:
                     $ ld connect filespec.dsk LDA1: -
                         [/tracks=XXX] [/sectors=XXX] [/cylinders=XXX]
                   You may want to the pick the tracks, sectors and
                   cylinders values to match the output geometry, and
                   you will want to assume CHKSCB errors may arise when
                   ANALYZE/DISK_STRUCTURE is used in cases where the
                   geometries do not match.
                   These particular CHKSCB geometry-related messages
                   reported by ANALYZE/DISK_STRUCTURE are entirely benign,
                   are commonly and widely seen on existing recorded
                   optical media used with OpenVMS. These messages can
                   safely be ignored. An example of the messages typical
                   of an analysis of a recorded volume follows:
                   $ analyze/disk dqa1:
                   Analyze/Disk_Structure for _VMS$DQA1: started on
                   dd-mmm-yyyy  hh:mm:ss.cc
                   %ANALDISK-W-CHKSCB, invalid storage control block, RVN 1
                   %ANALDISK-I-OPENQUOTA, error opening QUOTA.SYS
                   -SYSTEM-W-NOSUCHFILE, no such file
                   SYS$LDDRIVER, SYS$DKDRIVER and SYS$DQDRIVER do not
                   currently implement consistent geometry-related
                   synthesis; the drivers calculate different pseudo-
                   geometries for the same input device maximum block
                   count. (Note that the disk geometry values are entirely
                   synthetic constructs on most (all?) recent storage
                   devices, whether magnetic disk or optical media.
                   Save for some messages generated within analysis
                   and reporting tools, the values are also entirely
                   inconsequential. Again, these messages can safely be
                   Here is the SYS$DQDRIVER geometry from a typical 600 MB
                   CD-R/RW DQcu:-type disk device:
                      Total blocks:     1200000   Sectors per track:   33
                      Total cylinders:  1102      Tracks per cylinder: 33
                   Here is the SYS$DKDRIVER geometry (yes, the drivers
                   can disagree in the synthesis) from a typical 600 MB
                   CD-R/RW DKcu:-type disk device:
                      Total blocks      1200008    Sectors per track   4
                      Total cylinders   37501    Tracks per cylinder   8
                   For each master to be created, initialize and populate
                   the master volume:
                     $ INITIALIZE /SYSTEM [/ERASE] -
                           [/CLUSTER=n] [/GPT] [/...] -
                           LDA1: volumelabel
                     $ MOUNT LDA1: volumelabel
                     $ !...  populate the target volume as required
                     $ DISMOUNT LDA1:
                   You will want to consider the use of INITIALIZE/ERASE,
                   and particularly if there is the potential for
                   sensitive data stored on the underlying disk device.
                   Without the disk erasure during initialization, the
                   contents of (uninitialized or otherwise unerased)
                   blocks underneath the logical disk file can be
                   replicated out onto the target media.
                   If working to create OpenVMS I64 system disks, you will
                   generally want to select the /GPT option to create the
                   necessary GPT-related files within the created disk
                   volume structure. INITIALIZE/GPT is the default for the
                   OpenVMS I64 initializations, though it must currently
                   be explicitly selected when initializing volumes on
                   OpenVMS Alpha and OpenVMS VAX platforms; volumes that
                   are intended for later use bootstrapping on OpenVMS I64
                   Additionally, the cluster factor may be best chosen
                   as a multiple of four (4) if the target volume is a
                   system disk, as this causes the proper alignment of
                   the core bootstrap files.  For related information,
                   please see INITIALIZE/CLUSTER and see section
                   To record the contents of the master volume to the
                   CD-R/RW or DVD+R/RW SCSI or ATAPI device, please
                   review the command(s) associated with your chosen
                   recording tool.  If you are using a recording device
                   on another operating system platform, you will want
                   to use the binary or raw recording mode of the tool,
                   after having performed an FTP binary transfer of the
                   LD partition file to the target platform (if not
                   recording on OpenVMS).
                   The typical recording operation requires the selection
                   of what most recording tools refer to as a raw, binary,
                   or image transfer (to perform a block-by-block recording
                   of the contents of the LD partition file out onto the
                   medium), the Disk-at-Once (DAO) recording selection
                   is common, and the output recording format is usually
                   ISO Mode 1 data using 2048 byte blocking.  Consult
                   the documentation for the particular chosen recording
                   tool for additional details and required syntax.
          1.2.1  Creating Bootable OpenVMS Media
                   This section contains information on creating bootable
                   OpenVMS media, and is not specifically related to the
                   chosen recording utility.
                   To create bootable media, there are a variety of ways
                   to transfer hp OpenVMS operating system files files
                   onto the target media. This section will describe the
                   use of certain tools provided with hp OpenVMS, as well
                   as specific considerations related to bootstrapping
                   optical media.
  Write-locked Bootable Media
                   If you are using SYS$SYSTEM:AXPVMS$PCSI_INSTALL_MIN.COM
                   or SYS$SYSTEM:I64VMS$PCSI_INSTALL_MIN.COM to create
                   bootable OpenVMS environment, remember to mark the the
                   target medium as being write-locked; remember to set
                   the WLKSYSDSK system parameter in the LD master copy to
                   The following assumes the target device for the
                   mastering is LDA1:, and assumes [SYSE], the default
                   system root for AXPVMS$PCSI_INSTALL_MIN or
                   I64VMS$PCSI_INSTALL_MIN operations:
                   $ run sys$system:sysman
                   SYSMAN> parameters use lda1:[syse.sysexe]alphavmssys.par
                   SYSMAN> parameters show wlksysdsk
                   SYSMAN> parameters set wlksysdsk 1
                   SYSMAN> parameters write lda1:[syse.sysexe]alphavmssys.par
                   $ run sys$system:sysman
                   SYSMAN> parameters use lda1:[syse.sysexe]ia64vmssys.par
                   SYSMAN> parameters show wlksysdsk
                   SYSMAN> parameters set wlksysdsk 1
                   SYSMAN> parameters write lda1:[syse.sysexe]ia64vmssys.par
                   Failure to establish the correct write-lock setting and
                   failure to set up the proper system root can lead to
                   bootstrap problems when booting the OpenVMS operating
                   system from CD or DVD media.
  The Bootblock Structures
                   If not invoked within the tools utilized to transfer
                   the hp OpenVMS files onto the target logical disk, you
                   must also directly invoke the SET BOOTBLOCK utility
                   (or run SYS$SETBOOT.EXE directly) to write the I64
                   EFI console bootstrap structures specific to OpenVMS
                   I64 onto the disk, or you must invoke the hp OpenVMS
                   WRITEBOOT utility to write OpenVMS VAX or OpenVMS Alpha
                   bootstrap structures.
                   OpenVMS I64 bootstraps requires one additional key
                   consideration, the target sector size for the medium.
                   With magnetic disk bootstraps, the sector size is
                   always 512 bytes. With optical media, the sector size
                   is typically 2048 bytes.
                   When selecting the bootstrap structures to write to
                   an OpenVMS I64 system disk using the SET BOOTBLOCK
                   utility, the default is to write 512-byte structures.
                   The use of 2048-byte sector structures must be manually
                   selected when writing to the logical disk; when writing
                   to a logical disk that will eventually master optical
                   The sector size selection has no effect on any other
                   structures nor on any other disk data written to
                   the disk, nor any effects on the running hp OpenVMS
                   environment once OpenVMS has bootstrapped; all disks
                   will present the appearance of 512-byte blocks once
                   OpenVMS has bootstrapped.   This 2048-byte sector
                   size selection only affects the I64 EFI bootstrap
                   structures, and is only required when mastering for
                   OpenVMS I64 optical media bootstraps.
                   An example of selecting the larger block size with SET
                   BOOTBLOCK follows:
                       SET BOOTBLOCK/BLOCK_SIZE=2048/PRESERVE=SIGNATURE ddcu:
                   The INITIALIZE[/ERASE][/GPT]/CLUSTER=4 command -- or
                   another multiple of four (4) -- will properly align the
                   two core bootstrap files (SYS$LOADABLE_IMAGES:SYS$EFI.SYS
                   and SYS$MAINTENANCE:SYS$DIAGNOSTICS.SYS) as required by
                   SET BOOTBLOCK.  These are the only two files that must
                   be aligned to the 2048-byte sector boundary.
  Generating a System Disk Master
                   Use LD CREATE ddcu:[dir]partition.DSK/SIZE=size to
                   create the partition, set the caching attributes
                   on the file to disable XFC caching, then issue LD
                   CONNECT ddcu:[dir]partition.DSK LDcu: to connect
                   the LD device, full initialization of the volume
                   including erasure of the master partition, then use
                   Alpha, SYS$SYSTEM:I64VMS$PCSI_INSTALL_MIN.COM on
                   OpenVMS I64, or BACKUP/IMAGE or otherwise to load the
                   logical disk partition with the contents of a system
                   disk. MOUNT and then configure the volume contents as
                   required for the application, including modifying the
                   WLKSYSDSK system parameter as discussed earlier, then
                   (if the target is OpenVMS I64) use the DCL command
                   SET BOOTBLOCK/BLOCK_SIZE=2048/IA64 LDcu: to write
                   the bootblock appropriate for a 2048-byte block device,
                   DISMOUNT the device, then use the prefered recording
                   tool to transfer LDcu: to DQcu:; to transfer the
                   contents to the target recording device.
                   If the target is OpenVMS Alpha, use WRITEBOOT.EXE in
                   place of SET BOOTBLOCK or SYS$SETBOOT.EXE.
                   If you have the OpenVMS I64 cross-tools tools kit
                   installed and are generating a system disk for use
                   with OpenVMS I64, use of INITIALIZE/ERASE/GPT/CLUSTER
                   is recommended.  The direct invocation of the image
                   SYS$SETBOOT.EXE (which triggers a prompting mode, akin
                   to that of WRITEBOOT) or the use of the associated DCL
                   command SET BOOTBLOCK command is also recommended.
                   (SET BOOTBLOCK/SYS$SETBOOT.EXE applies to OpenVMS I64,
                   and WRITEBOOT applies to OpenVMS VAX and OpenVMS Alpha.)
                   When creating an OpenVMS Alpha system disk within the
                   partition, the following is the general sequence:
                   $ LD CREATE ddcu:[dir]partition.DSK/SIZE=size
                   $ LD CONNECT ddcu:[dir]partition.DSK LDcu:
                   $ INITIALIZE[/ERASE][...] LDcu: vollab
                   $! or BACKUP/IMAGE ddcu: LDcu:
                   $ MOUNT LDcu: vollab
                   $ run sys$system:sysman
                   SYSMAN> parameters use ldcu:[syse.sysexe]alphavmssys.par
                   SYSMAN> parameters set wlksysdsk 1
                   SYSMAN> parameters write ldcu:[syse.sysexe]alphavmssys.par
                   SYSMAN> exit
                   $ RUN SYS$SYSTEM:WRITEBOOT
                   $ DISMOUNT LDcu:
                   $ [prefered DVD recording tool]
                   When creating an OpenVMS I64 system disk in the disk
                   partition, the following is the general sequence:
                   $ LD CREATE ddcu:[dir]partition.DSK/SIZE=size
                   $ LD CONNECT ddcu:[dir]partition.DSK LDcu:
                   $ INITIALIZE[/ERASE][/GPT][/CLUSTER=n][...] LDcu: vollab
                   $ @SYS$SYSTEM:I64VMS$PCSI_INSTALL_MIN.COM
                   $! or BACKUP/IMAGE ddcu: LDcu:
                   $ MOUNT LDcu: vollab
                   $ run sys$system:sysman
                   SYSMAN> parameters use ldcu:[syse.sysexe]ia64vmssys.par
                   SYSMAN> parameters set wlksysdsk 1
                   SYSMAN> parameters write ldcu:[syse.sysexe]ia64vmssys.par
                   SYSMAN> exit
                   $ SET BOOTBLOCK/BLOCK_SIZE=2048/IA64 LDcu:
                   $ DISMOUNT LDcu:
                   $ [prefered DVD recording tool]
  The Bootstrap Root
                   If the selected system root for the bootable medium
                   is [SYSE], remember that the associated SRM console
                   bootstrap command is:
                       >>> BOOT -FLAGS E,0
                   If you want the default bootstrap to be SYS0, which is
                   the common setting for bootstraps from various devices,
                   please remember to create the root in [SYS0] using the
                   available AXPVMS$PCSI_INSTALL_MIN command syntax, or
                   remember to add an alias using a DCL command similar to
                   the following:
                       $ SET FILE/ENTER=LDA1:[000000]SYS0.DIR -
  The Core Utilities
                   For information on AXPVMS$PCSI_INSTALL_MIN, on SYSMAN,
                   on the WLKSYSDSK system parameter, on SET FILE/ENTER,
                   on the SRM console, on WRITEBOOT and on SET BOOTBLOCK,
                   and other related materials, please see the hp OpenVMS
          1.3  LD Logical Disk Driver
                   This description assumes LD (latent in V7.3-1 and later,
                   though the command verb must be manually loaded into
                   DCLTABLES, or the LD command verb can be loaded into
                   DCLTABLES using the LD731 kit found on OpenVMS Freeware
                   V6.0) has been configured and started. The LD command
                   verb and related portions of the interface are expected
                   to be available by default in OpenVMS V8.2 and later.
                   LD provides a pseudo disk, sometimes known as an
                   emulated or file-based or loop disk, and the user
                   interface is comprised of a LD utility and its
                   associated DCL command verb, and a device driver known
                   as SYS$LDDRIVER. LD provides the mechanism by which the
                   master copy of the media can be created. (Other similar
                   pseudo disk packages can potentially be used, there are
                   no specific requirements for LD and SYS$LDDRIVER. Other
                   pseudo disk packages have not been tested.)
                   Do not configure LD devices larger than four gigabytes
                   (GB) prior to the version of SYS$LDDRIVER integrated in
                   OpenVMS Alpha V7.3-1; older kits and older versions have
                   a four GB addressing limit. If you are using the version
                   of LD shipped with V7.3-1 or are using a later OpenVMS
                   release, this note and this restriction does not apply.
                   If you are using an LD06* or an older VMSINSTAL kit,
                   please upgrade before working with larger disks.
          1.3.1  XFC and LD
                   When creating and initially configuring the LD logical
                   disk file (partition file) as discussed in Section 1.2,
                   you will want to use the following command sequence:
                     $ ld create [/log] [/size=XXX] [/contiguous] filespec.dsk
                     $ SET FILE /CACHING_ATTRIBUTE=NO_CACHING filespec.dsk
                   Note that only the LD logical disk file (a backing
                   partition file) should have XFC file caching disabled.
                   Files that are not logical disk files and that are not
                   accessed via the LD device should have XFC caching left
                   A correction to the operations and communications
                   between LD and XFC is expected. Once available, the
                   logical disk file can be left with XFC caching enabled.
                   Change the XFC cache settings on the logical disk file
                   once. Having or altering the settings to enable XFC
                   caching can lead to data inconsistencies between the
                   LD contents and the XFC cache contents of the logical
                   disk file, and to errant or unexpected recorded media
                   contents, and is not recommended.
                   When reading from an input file, XFC caching should
                   be enabled. When transfering data from an input LDcu:
                   device, caching should be disabled on the LD logical
                   disk file (partition file).
                   It is strongly recommended that the XFC caching setting
                   be toggled exactly once on any particular file, and
                   subsequently left unchanged for current and future
                   operations on the specified file. Repeatedly toggling
                   the XFC caching setting is not recommended, and
                   can result in corrupted file data and/or corrupted
          1.3.2  IDE/ATAPI Bus Interface
                   If you have an Acer or other DMA-capable IDE interface,
                   the version of SYS$DQDRIVER shipped with V7.3-2 will
                   not permit the formatting nor the reformatting of
                   rewritable media, and is expected to mishandle the
                   formatting (FORMAT_UNIT) request. The CMD649 on OpenVMS
                   I64, and the Cypress and the Intel PIIXE IDE interfaces
                   on both OpenVMS I64 and OpenVMS Alpha are expected to
                   permit the (re)formatting operation to succeed. The
                   Acer is not expected to permit reformatting operations.
                   Table 1-1 contains various of the AlphaServer and
                   AlphaStation IDE controller hardware identification
          Table 1-1  IDE/ATAPI Controllers
                   Acer              0x522910B9        No
                   CMD649            0x06491095        Yes
                   Cypress           0xC6931080        Yes
                   The ANALYZE/SYSTEM (SDA) command CLUE CONFIG can also
                   potentially be used to identify the particular IDE
                   controller in use. Look for the identification of the
                   controller associated with the DQcu: devices. These
                   values are also directly visible from the SRM console.
                   In SYS$DQDRIVER version X-48 and related versions
                   (including the driver version shipping with OpenVMS
                   Alpha V7.3-2), the error is the omission of the FORMAT_
                   UNIT command code (0x04) from within the following
                   SYS$DQDRIVER.C device driver code:
                           if ( (packet [0] == 0x0A) || (packet [0] == 0x2A)  ||
                                (packet [0] == 0xAA) || (packet [0] == 0x55) )
                               data_dir = TRUE;
                   The following are the packet command codes that should
                   set the data_dir variable to TRUE:
                       WRITE_6 (0x0a), WRITE_10 (0x2a), WRITE_12 (0xaa),
                       WRITE_VERIFY_10 (0x2e), MODE_SELECT_10 (0x55),
                       FORMAT_UNIT (0x04), RESERVE_TRACK (0x53),
                       SEND_DVD_STRUCT (0xbf), SEND_KEY (0xa3),
                       SEND_OPC_INFO (0x54), and WRITE_BUFFER (0x3b).
                   The FORMAT_UNIT packet command code is used to
                   initialize and to reformat RW-type rewritable media.
                   The FORMAT_UNIT packet command is not otherwise used,
                   nor used with other recordable media types.
                   The underlying SYS$DQDRIVER issue might be corrected
                   in an unspecified future version of SYS$DQDRIVER. No
                   schedule and no plans for the correction have been
                   announced, and the code change is not present within
                   the OpenVMS V8.2 source code pool, as of 06-Aug-2004.
                   The change is not present in the OpenVMS E8.2 field
                   test release.

answer written or last revised on ( 10-SEP-2004 )

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