hpux 10.20 - hpux (1)



 NAME
      hpux - HP-UX bootstrap

 SYNOPSIS
      hpux [-F] [-lm] [-a[C|R|S|D] devicefile] [-fnumber] [-istring] [boot]
      [devicefile]
      hpux ll [devicefile] (same as hpux ls -aFln)
      hpux ls [-aFiln] [devicefile]
      hpux set autofile devicefile string
      hpux show autofile [devicefile]
      hpux -v
      hpux restore devicefile (Series 700 only; see DEPENDENCIES.)

 DESCRIPTION
      hpux is the HP-UX specific secondary system loader (SSL) utility for
      bootstrap (see isl(1M) for the initial system loader).  It supports
      the operations summarized below, as shown in the SYNOPSIS and detailed
      later in this DESCRIPTION.

           boot                  Loads an object file from an HP-UX file
                                 system or raw device and transfers control
                                 to the loaded image.  (Note, the boot
                                 operation is position dependent).

           ll                    Lists the contents of HP-UX directories in
                                 a format similar to ls -aFln.  (See ls(1);
                                 ls only works on a local disk with a HFS
                                 file system).

           ls                    Lists the contents of HP-UX directories.
                                 (See ls(1); ls only works on a local disk
                                 with a HFS file system).

           show autofile         Displays the contents of the autoexecute
                                 file.

           set autofile          Changes the contents of the autoexecute
                                 file to that specified by string.

           -v                    Displays the release and version numbers of
                                 the hpux utility.

           restore               Recovers the system from a properly
                                 formatted bootable tape.  (Series 700
                                 specific; see DEPENDENCIES.)

      hpux commands can be given interactively from the keyboard, or
      provided in an isl autoexecute file.

      hpux is limited to operations on the interface initialized by pdc(1M).
      In most cases, operations are limited to the boot device interface.

    Notation
      hpux accepts numbers (numeric constants) in many of its options.
      Numbers follow the C language notation for decimal, octal, and
      hexadecimal constants.  A leading 0 (zero) implies octal and a leading
      0x or 0X implies hexadecimal.  For example, 037, 0x1F, 0X1f, and 31
      all represent the same number, decimal 31.

      hpux boot, ll, ls, set autofile, show autofile, and restore operations
      accept devicefile specifications, which have the following format:

           manager(w/x.y.z;n)filename

      The devicefiles specification is comprised of a device name and a file
      name.  The device name (manager(w/x.y.z;n)), consists of a generic
      name of an I/O system manager (device or interface driver) such as
      disc, a hardware path to the device, and minor number.  The manager
      name can be omitted entirely if the default is used.  w/x.y.z is the
      physical hardware path to the device, identifying bus converters, slot
      numbers, and hardware addresses.  For Series 700 machines, there are a
      set of mnemonics that can be used instead of the hardware paths.  The
      n is the minor number that controls manager-dependent functionality.
      The file name part, filename, is a standard HP-UX path name.  Some
      hpux operations have defaults for particular components.  A devicefile
      specification containing a device part only specifies a raw device.  A
      devicefile specification containing a file name implies that the
      device contains an HP-UX file system, and that the filename resides in
      that file system.

      A typical boot devicefile specification is

           disc(2/4.0.0;0)/stand/vmunix

      The manager is disc, the hardware path to the disk device is 2/4.0.0,
      the minor number shown as 0 by default, and the /stand/vmunix is the
      filename for the boot device.

      hpux now supports a consolidated list of managers: disc, tape, and
      lan.  The manager disc manages all CS/80 disks connected via HP-IB
      (formerly disc0); CS/80 disks connected via the HP27111 interface
      (formerly disc2); CS/80 disks connected via NIO HP-IB (formerly
      disc1); all disks connected via SCSI, (formerly disc3), and all
      autochanger disk devices (formerly disc30).  The manager lan manages
      remote boot through the HP28652A NIO based LAN interface (formerly
      lan1).  Remote boot is currently supported on this card only and not
      on any CIO-based LAN card.  The manager tape manages the HP7974,
      HP7978, and HP7980 tape drives via HP-IB (formerly tape1) and tape
      drives via SCSI (formerly tape2).

      The hardware path in a devicefile specification is a string of
      numbers, each suffixed by slash, (/), followed by a string of numbers
      separated by dots (.), each number identifying a hardware component

      notated sequentially from the bus address to the device address.  A
      hardware component suffixed by a slash indicates a bus converter and
      may not be necessary on your machine.  For example, in w/x.y.z w is
      the address of the bus converter, x is the address of the MID-BUS
      module, y is the CIO slot number, and z is the HP-IB address or
      HP27111 bus address.

      The minor number, n, in a devicefile specification controls driver-
      dependent functionality.  (See the manual, Configuring HP-UX for
      Peripherals, for minor-number bit assignments of specific drivers).

      File names are standard HP-UX path names.  No preceding slash (/) is
      necessary and specifying one will not cause problems.

    Defaults
      Default values chosen by hpux to complete a command are obtained
      through a sequence of steps.  First, any components of the command
      specified explicitly are used.  If the command is not complete, hpux
      attempts to construct defaults from information maintained by pdc (see
      pdc(1M)).  If sufficient information to complete the command is
      unavailable, the autoexecute file is searched.  If the search fails,
      any remaining unresolved components of the command are satisfied by
      hard-coded defaults.

      There is no hard-coded default choice for a manager; if none can be
      chosen, hpux reports an error.

      When the hardware path to the boot device is not specified, hpux
      defaults to information maintained by pdc.  The hardware path element
      has no hard-coded default.

      If the minor number element is not supplied, hpux takes its default
      from the autoexecute file.  Failing that, the hard-coded default of 0
      is used.

      For the boot command, a devicefile specification without a file name
      indicates that the boot device does not contain an HP-UX file system.
      hpux interprets this as a NULL (instead of missing) file name and does
      not search for a default.  If the entire devicefile specification is
      missing, hpux searches for a default; either the autoexecute file
      contents or the hard-coded default is chosen.

      There are two possible hard-coded default devicefile specifications.
      One hard-coded default devicefile specification is /vmunix.  The other
      hard-coded default devicefile specification is /stand/vmunix.

      If you have a LVM system where the boot volume and the root volume are
      on different logical volumes, the kernel would be /vmunix.  This is
      because the boot volume will be mounted under /stand when the system
      is up.


      For all other configurations, the kernel would be /stand/vmunix.

      The search order for the hard-coded defaults is /stand/vmunix and then
      /vmunix.

    boot Operation
      The boot operation loads an object file from an HP-UX file system or
      raw device as specified by the optional devicefile.  It then transfers
      control to the loaded image.

      Any missing components in a specified devicefile are supplied with a
      default.  For example, a devicefile of vmunix.new would actually
      yield:

           disc(8.0.0;0)vmunix.new

      and a devicefile of (8.0.1)/stand/vmunix, for booting from the disk at
      HP-IB address 1, would yield

           disc(8.0.1;0)/stand/vmunix

      Regardless of how incomplete the specified devicefile may be, boot
      announces the complete devicefile specification used to find the
      object file.  Along with this information, boot gives the sizes of the
      TEXT, DATA, and BSS, segments and the entry offset of the loaded
      image, before transferring control to it.

      The boot operation accepts several options.  Note that boot options
      must be specified positionally as shown in the syntax statement in the
      SYNOPSIS.  Options for the boot operations are as follows:

           -a[C|R|S|D] devicefile    Accept a new location (as specified by
                                     devicefile) and pass it to the loaded
                                     image.  If that image is an HP-UX
                                     kernel, the kernel will erase its
                                     predefined I/O configuration, and
                                     configure in the specified devicefile.
                                     If the C, R, S, or D option is
                                     specified, the kernel configures the
                                     devicefile as the console, root, swap,
                                     or dump device, respectively.  Note
                                     that -a can be repeated multiple times.

           -fnumber                  Use the number and pass it as the flags
                                     word to the loaded image.

           -istring                  Set the initial run-level for init (see
                                     init(1M)) when booting the system.  The
                                     run-level specified will override any
                                     run-level specified in an initdefault
                                     entry in /etc/inittab (see inittab(4)).

           -lm                       Boot the system in LVM maintenance
                                     mode, configure only the root volume,
                                     and then initiate single user mode.

           -F                        Use with SwitchOver/UX software.
                                     Ignore any locks on the boot disk.  The
                                     -F option should be used only when it
                                     is known that the processor holding the
                                     lock is no longer running.  (If this
                                     option is not specified and a disk is
                                     locked by another processor, the kernel
                                     will not boot from it, to avoid the
                                     corruption that would result if the
                                     other processor were still using the
                                     disk).

      boot places some restrictions on object files it can load.  It accepts
      only the HP-UX magic numbers EXECMAGIC (0407), SHAREMAGIC (0410), and
      DEMANDMAGIC (0413).  See magic(4).  The object file must contain an
      Auxiliary Header of the HPUX_AUX_ID type and it must be the first
      Auxiliary Header (see a.out(4)).

    ll and ls Operations
      The ll and ls operations list the contents of the HP-UX directory
      specified by the optional devicefile.  The output is similar to that
      of ls -aFl command, except the date information is not printed.

      The default devicefile is generated just as for boot, defaulting to
      the current directory.

    set autofile Operation
      The set autofile operation overwrites the contents of the autoexecute
      file, autofile, with the string specified (see autoexecute in the
      EXAMPLES section).

    show autofile Operation
      The show autofile operation displays the contents of the autoexecute
      file, autofile (see autoexecute in the EXAMPLES section).

 DIAGNOSTICS
      If an error is encountered, hpux prints diagnostic messages to
      indicate the cause of the error.  These messages fall into the
      General, Boot, Copy, Configuration, and System Call categories.
      System Call error messages are described in errno(2).  The remaining
      messages are listed below.

    General
      bad minor number in devicefile spec
           The minor number in the devicefile specification is not
           recognized.


      bad path in devicefile spec
           The hardware path in the devicefile specification is not
           recognized.

      command too complex for parsing
           The command line contains too many arguments.

      no path in devicefile spec
           The devicefile specification requires (but does not contain) a
           hardware path component.

      panic (in hpuxboot): (display==number, flags==number)) string
           A severe internal hpux error has occurred.  Report to your
           nearest HP Field Representative.

    Boot
      bad magic
           The specified object file does not have a recognizable magic
           number.

      bad number in flags spec
           The flags specification in the -f option is not recognized.

      Exec failed: Cannot find /stand/vmunix or /vmunix.
           Neither /stand/vmunix or /vmunix could be found.

      booting from raw character device
           In booting from a raw device, the manager specified only has a
           character interface, which might cause problems if the block size
           is incorrect.

      isl not present, please hit system RESET button to continue
           An unsuccessful boot operation has overlaid isl in memory.  It is
           impossible to return control to isl.

      short read
           The specified object file is internally inconsistent; it is not
           long enough.

      would overlay
           Loading the specified object file would overlay hpux.

    Configuration
      cannot add path, error number
           An unknown error has occurred in adding the hardware path to the
           I/O tree.  The internal error number is given.  Contact your HP
           Field Representative.

      driver does not exist
           The manager specified is not configured into hpux.


      driver is not a logical device manager
           The manager named is not that of a logical device manager and
           cannot be used for direct I/O operations.

      error rewinding device"
           An error was encountered attempting to rewind a device.

      error skipping file
           An error was encountered attempting to forward-space a tape
           device.

      negative skip count
           The skip count, if specified, must be greater than or equal to
           zero.

      no major number
           The specified manager has no entry in the block or character
           device switch tables.

      path incompatible with another path
           Multiple incompatible hardware paths have been specified.

      path long
           The hardware path specified contains too many components for the
           specified manager.

      path short
           The hardware path specified contains too few components for the
           specified manager.

      table full
           Too many devices have been specified to hpux.

 EXAMPLES
      As a preface to the examples which follow, here is a brief overview of
      HP-UX system boot-up sequences.

    Automatic Boot
      Automatic boot processes on various HP-UX systems follow similar
      general sequences.  When power is applied to the HP-UX system
      processor, or the system Reset button is pressed, processor-dependent
      code (firmware) is executed to verify hardware and general system
      integrity (see pdc(1M)).  After checking the hardware, pdc gives the
      user the option to override the autoboot sequence by pressing the Esc
      key.  At that point, a message resembling the following usually
      appears on the console.

           (c) Copyright. Hewlett-Packard Company. 1994.
           All rights reserved.



           PDC ROM rev. 130.0
           32 MB of memory configured and tested.

           Selecting a system to boot.
           To stop selection process, press and hold the ESCAPE key...

      If no keyboard activity is detected, pdc commences the autoboot
      sequence by loading isl (see isl(1M)) and transferring control to it.
      Since an autoboot sequence is occurring, isl finds and executes the
      autoexecute file which, on an HP-UX system, requests that hpux be run
      with appropriate arguments.  Messages similar to the following are
      displayed by isl on the console:

           Booting from: scsi.6  HP 2213A
           Hard booted.
           ISL Revision A.00.09  March 27, 1990
           ISL booting  hpux boot disk(;0)/stand/vmunix

      hpux, the secondary system loader, then announces the operation it is
      performing, in this case boot, the devicefile from which the load
      image comes, and the TEXT size, DATA size, BSS size, and start address
      of the load image, as shown below, before control is passed to the
      image.

           Booting disk(scsi.6;0)/stand/vmunix
           966616+397312+409688 start 0x6c50

      The loaded image then displays numerous configuration and status
      messages.

    Interactive Boot
      To use hpux interactively, isl must be brought up in interactive mode
      by pressing the Esc key during the interval allowed by pdc.  pdc then
      searches for and displays all bootable devices and presents a set of
      boot options.  If the appropriate option is chosen, pdc loads isl and
      isl interactively prompts for commands.  Information similar to the
      following is displayed:

           Selection process stopped.

           Searching for Potential Boot Devices.
           To terminate search, press and hold the ESCAPE key.

           Device Selection    Device Path             Device Type
           -------------------------------------------------------------
           P0                  scsi.6.0                QUANTUM PD210S
           P1                  scsi.1.0                HP      2213A
           p2                  lan.ffffff-ffffff.f.f   hpfoobar

           b)  Boot from specified device
           s)  Search for bootable devices

           a)  Enter Boot Administration mode
           x)  Exit and continue boot sequence

           Select from menu: b p0 isl

           Trying scsi.6.0
           Boot path initialized.
           Attempting to load IPL.

           Hard booted.
           ISL Revision A.00.2G  Mar  27, 1994
           ISL>

      Although all of the operations and options of hpux can be used from
      isl interactively, they can also be executed from an autoexecute file.
      In the examples below, user input is the remainder of the line after
      each ISL> prompt shown.  The remainder of each example is text
      displayed by the system.  Before going over specific examples of the
      various options and operations of hpux, here is an outline of the
      steps taken in the automatic boot process.  Although the hardware
      configuration and boot paths shown are for a single Series 800
      machine, the user interfaces are consistent across all models.  When
      the system Reset button is depressed, pdc executes self-test, and
      assuming the hardware tests pass, pdc announces itself, sends a BELL
      character to the controlling terminal, and gives the user 10 seconds
      to override the autoboot sequence by entering any character.  Text
      resembling the following is displayed on the console:

           Processor Dependent Code (PDC) revision 1.2
           Duplex Console IO Dependent Code (IODC) revision 3

           Console path        = 56.0.0.0.0.0.0   (dec)
                                 38.0.0.0.0.0.0   (hex)

           Primary boot path   = 44.3.0.0.0.0.0   (dec)
                                2c.00000003.0.0.0.0.0   (hex)

           Alternate boot path = 52.0.0.0.0.0.0   (dec)
                                 34.0.0.0.0.0.0   (hex)

           32 MB of memory configured and tested.

           Autosearch for boot path enabled

           To override, press any key within 10 seconds.

      If no keyboard character is pressed within 10 seconds, pdc commences
      the autoboot sequence by loading isl and transferring control to it.
      Because an autoboot sequence is occurring, isl merely announces
      itself, finds and executes the autoexecute file which, on an HP-UX
      system, requests that hpux be run with appropriate arguments.  The

      following is displayed on the console.

           10 seconds expired.
           Proceeding with autoboot.

           Trying Primary Boot Path
           ------------------------
           Booting...
           Boot IO Dependent Code (IODC) revision 2

           HARD Booted.

           ISL Revision A.00.2G Mar  20, 1994

           ISL booting  hpux

      hpux then announces the operation it is performing, in this case boot,
      the devicefile from which the load image comes, and the TEXT size,
      DATA size, BSS size, and start address of the load image.  The
      following is displayed before control is passed to the image.

           Boot
           : disc3(44.3.0;0)/stand/vmunix
           3288076 + 323584 + 405312 start 0x11f3e8

      Finally, the loaded image displays numerous configuration and status
      messages, then proceeds to init run-level 2 for multiuser mode of
      operation.

      isl must be brought up in interactive mode to use the operations and
      options of hpux.  To do this, simply enter a character during the 10
      second interval allowed by pdc.  pdc then asks if the primary boot
      path is acceptable.  Answering yes (Y) is usually appropriate.  pdc
      then loads isl and isl interactively prompts for commands.  The
      following lines show the boot prompt, the Y response, subsequent boot
      messages, and finally the Initial System Loader (ISL) prompt that are
      sent to the display terminal:

           Boot from primary boot path (Y or N)?> y
           Interact with IPL (Y or N)?> y

           Booting...
           Boot IO Dependent Code (IODC) revision 2

           HARD Booted.

           ISL Revision A.00.2G Mar  20, 1994

           ISL>



      Although all of the operations and options of hpux can be used from
      isl interactively, they can also be executed from an autoexecute file.
      In the examples below, all user input follows the ISL> prompt on the
      same line.  Subsequent text is resultant messages from the ISL.

    Default Boot
      Entering hpux initiates the default boot sequence.  The boot path read
      from pdc is 8.0.0, the manager associated with the device at that path
      is disc, the minor number, in this case derived from the autoexecute
      file, is 4 specifying section 4 of the disk, and the object file name
      is /stand/vmunix.

           ISL> hpux

           Boot
           : disc3(44.3.0;0)/stand/vmunix
           3288076 + 323584 + 405312 start 0x11f3e8

    Booting Another Kernel
      In this example, hpux initiates a boot operation where the name of the
      object file is vmunix.new.

           ISL> hpux vmunix.new

           Boot
           : disc3(44.3.0;0)/stand/vmunix.new
           3288076 + 323584 + 405312 start 0x11f3e8

    Booting From Another Section
      In this example (shown for backward compatibility), a kernel is booted
      from another section of the root disk.  For example, suppose kernel
      development takes place under /mnt/azure/root.port which happens to
      reside in its own section, section 3 of the root disk.  By specifying
      a minor number of 3 in the above example, the object file
      sys.azure/S800/vmunix is loaded from /mnt/azure/root.port.

           ISL> hpux (;3)sys.azure/S800/vmunix

           Boot
           : disc(8.0.0;0x3)sys.azure/S800/vmunix
           966616+397312+409688 start 0x6c50

    Booting From Another Disk
      Only the hardware path and file name are specified in this example.
      All other values are boot defaults.  The object file comes from the
      file system on another disk.

           ISL> hpux (52.5.0.0)/stand/vmunix

           Boot
           : disc(52.5.0.0)/stand/vmunix

           966616+397312+409688 start 0x6c50

    Booting From LAN
      This example shows how to boot a cluster client from the LAN.  Though
      this example specifies a devicefile, you can also use default boot, as
      shown in a previous example.  For a boot operation other than default
      boot, the file name must be specified and can be no longer than 11
      characters.  Booting to isl from a local disk then requesting an image
      to be loaded from the LAN is not supported.

           ISL> hpux lan(32)/stand/vmunix

           Boot
           : lan(32;0x0)/stand/vmunix
           966616+397312+409688 start 0x6c50

    Booting To Single User Mode
      In this example, the -i option is used to make the system come up in
      run-level s, for single user mode of operation.

           ISL> hpux -is

           Boot
           : disc(8.0.0;0x0)/stand/vmunix
           966616+397312+409688 start 0x6c50

              Kernel Startup Messages Omitted

           INIT: Overriding default level with level 's'

           INIT: SINGLE USER MODE
           WARNING:  YOU ARE SUPERUSER !!
           #

    Booting With A Modified I/O Configuration
      Here, a tape driver is configured in at CIO slot 2, HP-IB address 0.
      Regardless of what was present in the kernel's original I/O
      configuration, the driver tape is now configured at that hardware
      path.  Similarly, mux0 is configured in at CIO slot 1 which is to be
      the console.  The only other devices configured are the console and
      root device, which boot derived from pdc.

           ISL> hpux -aC mux0(8.1) -a tape(8.2.0)

           Boot
           : disc(8.0.0;0x0)/stand/vmunix
           : Adding mux0(8.1;0x0)...
           : Adding tape(8.2.0;0x0)...
           966616+397312+409688 start 0x6c50
           Beginning I/O System Configuration.
           cio_ca0 address = 8

              hpib0 address = 0
                 disc0 lu = 0 address = 0
              mux0 lu = 0 address = 1
              hpib0 address = 2
                 tape1 lu = 0 address = 0
           I/O System Configuration complete.

              Additional Kernel Startup Messages Omitted

    Booting From A Raw Device
      This example shows booting from a raw device (that is, a device
      containing no file system).  Note that no file name is specified in
      the devicefile.  The device is an HP7974 tape drive, and therefore
      tape is the manager used.  The tape drive is at CIO slot 2, HP-IB
      address 3.  The first file on the tape will be skipped.  The minor
      number specifies a tape density of 1600 BPI with no rewind on close.
      Depending on the minor number, tape requires the tape be written with
      512 or 1024 byte blocks.

           ISL> hpux tape(8.2.3;0xa0000)

           Boot
           : tape(8.2.3;0xa0000)
           966616+397312+409688 start 0x6c50

    Displaying The Autoexecute File
      In this example, show autofile is used to print the contents of the
      autoexecute file residing in the boot LIF, on the device from which
      hpux was booted.  Optionally, a devicefile can be specified in order
      to read the autoexecute file from the boot LIF of another boot device.

           ISL> hpux show autofile
           Show autofile
           : AUTO file contains (hpux)

    Changing The Autoexecute File
      This example shows how to change the contents of the autoexecute file.
      Once done, the system can be reset, and the new command will be used
      during any unattended boot.

           ISL> hpux set autofile "hpux /stand/vmunix.std"
           Set autofile
           : disk(2/0/1.3.0.0.0.0.0;0)
           : AUTO file now contains "(hpux /stand/vmunix.std)"

    Listing Directory Contents
      The contents of the directory (/stand) on the root disk are listed.
      The format shows the file protections, number of links, user id, group
      id, and size in bytes for each file in the directory.  There are three
      available kernels to boot: vmunix, vmunix.test, and vmunix.prev.
      Listing the files over the LAN is not supported.

           ISL> hpux ll /stand

           Ls
           : disk(2/0/1.3.0.0.0.0.0;0)/stand
           dr-xr-xr-x    3 2        2              1024 ./
           drwxr-xr-x   17 0        0              1024 ../
           -rw-r--r--    1 0        3               191 bootconf
           drwxr-xr-x    2 0        0              1024 build/
           -rw-r--r--    1 0        0               632 ioconfig
           -rw-r--r--    1 0        3                82 kernrel
           -r--r--r--    1 0        3               426 system
           -rw-r--r--    1 0        3               437 system.prev
           -rwxr-xr-x    1 0        3           7771408 vmunix*
           -rwxr-xr-x    1 0        3           7771408 vmunix.prev*

    Getting The Version
      The -v option is used to get the version numbers of hpux.

           ISL> hpux -v

           Release: 10.00
           Release Version:
           @(#) X10.20.B HP-UX() #1: Dec  4 1995 16:55:08

 DEPENDENCIES
    Series 700 Only
      The restore operation is provided as a recovery mechanism in the event
      that a disk becomes totally corrupted.  It copies data from a properly
      formatted bootable tape to disk.  When this tape contains a backup
      image of the disk, the entire disk is restored.  To create a properly
      formatted tape (DDS ONLY), the following commands should be executed:

           dd if=/usr/lib/uxbootlf of=/dev/rmt/0mn bs=2k
           dd if=/dev/rdsk/1ss of=/dev/rmt/0m bs=64k

      The first dd puts a boot area on the tape, making it a bootable image
      (see dd(1)).  Once the boot image is on tape, the tape is not rewound.
      The next dd appends an image of the disk to the tape.  The entire
      process takes about one hour for a 660 MB HP2213 disk.  To avoid later
      problems with fsck after the disk is restored, bring the system to
      single user mode and type sync a few times before doing the second dd
      (see fsck(1M)).  Once created, the tape can be used to completely
      restore the disk:

           1. Insert the tape into the tape drive.

           2. Instruct the machine to boot to ISL from the tape.  This is
              usually done by specifying scsi.3 as the boot path.

           3. Enter the following in response to the ISL prompt:


                   ISL> hpux restore disk(scsi.1;0)

      This restores the disk image from the tape to the actual disk at
      scsi.1.  Any existing data on the disk will be lost.  This command
      destroys the contents of the device specified by devicefile.  The
      restoration process takes about one hour for a 660 MB drive.

      NOTE: There is a 2 GB limit on the amount of data that can be
      restored.  The tape and disk must be on the boot device interface.

      Also, this command may be replaced in the future by superior
      installation and recovery mechanisms.  At that time, this command will
      be removed.

 SEE ALSO
      boot(1M), fsck(1M), init(1M), isl(1M), pdc(1M), errno(2), a.out(4),
      inittab(4), magic(4).