scsicontrol(1m)                                                scsicontrol(1m)


NAME
     scsicontrol - probe and control scsi devices

SYNOPSIS
     /usr/sbin/scsicontrol [-CDHIRSacdegilmqsv] [-b blockize] device ...

DESCRIPTION
     scsicontrol may be used to print info from the SCSI inquiry commands,
     which normally indicate the device type, manufacturer, and similar info.
     Other options may be used show more data, or to issue commands that
     control the operation of the device, or the bus as a whole.  By using the
     debug option (-d), the exact command sent, and the data returned (if any)
     is displayed, along with more extensive error information.

     The device(s) may be specified without the normal /dev/scsi prefix, if
     desired.

     -C   Send the SGI-specific command that causes the CD-ROM drive to reply
          to the inquiry command (see -i below) as a CD-ROM drive.  On
          poweron, or after a SCSI bus reset (either as part of error recovery
          or from a user issued command), the CD-ROM drives sold by SGI
          respond to inquiry as a hard disk.  This was done because older
          systems would otherwise refuse to boot from the CD-ROM drive.

     -D   Send the SCSI self test (diagnostic) command to the device.

     -H   Send the SCSI halt, or stop, command.  This causes the device to
          stop the media, or in some cases, to unload it.

     -R   Display the Logical Unit Numbers of all configured logical units on
          the device.

     -S   Send the SCSI start, or load, command.  This causes the device to
          start the media, or in some cases, to load it.

     -a   Attempt to negotiate with the device to operate in asynchronous
          mode.  This will usually mean a lower data rate on the SCSI bus, but
          is less sensitive to scsi cabling problems, etc.  Some devices will
          negotiate synchronous mode, but may not work correctly in that mode.
          This can also be forced by changing the configuration variables for
          the scsi controller driver (e.g., the wd93_syncenable array in the
          file /var/sysgen/master.d/wd93).  Also see the -s option below.

     -d   Debug mode.  This causes all commands sent to the device and  the
          data that is returned, if any, to be printed.  Extensive information
          about errors is also printed when they occur.

     -e   Open the device in exclusive mode.  This will fail (with busy
          status) if the device is in use by some other process or SCSI
          driver.  If it succeeds, other opens will then fail.  This mode
          applies to the host controller driver, and does not issue any SCSI
          commands to the device (in particular, the reserve unit command is


          not sent).

     -g   Get the host adapter flags for this SCSI bus.  This is mostly of
          interest to driver writer's, but it does provide a way to determine
          if the SCSI disconnect option has been disabled on the bus.

     -i   Send the SCSI inquiry command, and display the info in a readable
          fashion.  The information typically includes the device type, the
          manufacturer, the SCSI version, and some of the optional SCSI
          features the device supports.  Also see -I below.

     -I   display all the data from the -i or -v options in both hex and ascii
          form.  Implies -i if neither -i or -v were given on the command
          line.

     -q   Quiet mode.  Don't print the name of each device as it is opened,
          unless an error occurs.

     -s   Attempt to negotiate with the device to operate in synchronous mode.
          This is normally done by the operating system when the device is
          first used, but that may fail, and the system will not then re-
          attempt to negotiate.  Some drivers will suppress the negotiation.
          Operating in synchronous mode will usually mean a higher data rate
          on the SCSI bus, but this mode is more sensitive to SCSI cabling
          problems.  Additionally, some devices will negotiate successfully
          for this mode, but will not work correctly.  Also see the -a option
          above.

     -v   Issue the SCSI inquiry command with the vital products modifier, and
          display the data in a readable fashion.  The vital product data
          often includes the serial number, and the additional information
          about the device.  Also see -I above.

     -c   Read Capacity. For devices that support the readcapacity command,
          print the capacity of the device, and if it's block oriented, the
          number of bytes per block.

     -b blocksize
          Set the blocksize (for disks, CDROMs, and some types of tape drives)
          to the given value, and also report the previous value.  blocksize
          may be given in decimal, hex (with leading 0x), or octal (with
          leading 0).  Not all devices support changing their block size.

     -l   Print the current values of all the supported logsense pages.  This
          can sometimes be useful in debugging device problems, but almost
          always requires the device specific manual from it's manufacturer,
          to be of use.

     -m   Print the current values of all the supported modesense pages.
          Mostly of use to people debugging problems or writing devscsi
          drivers.


FILES
     /dev/scsi/sc* - the generic scsi driver devices /dev/scsi/jag* - the
     generic scsi driver devices

SEE ALSO
     dsopen(3X), ds(7M), scsiha(1M), scsiha(7M).

NOTE
     This command is normally usable only by the superuser, because the
     standard permissions of the devices in /dev/scsi restrict access to other
     users.

     The source to this program is also shipped as sample source code in the
     irix_dev.gifts.scsi subsystem as part of IDO.


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