NAME

       blktool - Display or change block device settings

SYNOPSIS

       blktool [options] device [acoustic-mgmt nnn]

       blktool [options] device [block-sz nnn]

       blktool [options] device [bus-id]

       blktool [options] device [bus-state nnn]

       blktool [options] device [class]

       blktool [options] device [cd-speed nnn]

       blktool [options] device [defect-mgmt off|on]

       blktool [options] device [dev-keep-settings off|on]

       blktool [options] device [dev-read-ahead off|on]

       blktool [options] device [dma off|on]

       blktool [options] device [geometry]

       blktool [options] device [i2o-rcache nnn]

       blktool [options] device [i2o-wcache nnn]

       blktool [options] device [id]

       blktool [options] device [keep-settings off|on]

       blktool [options] device [media unlock|lock]

       blktool [options] device [multiple-count nnn]

       blktool [options] device [no-write-err off|on]

       blktool [options] device [pio-data 16-bit|32-bit]

       blktool [options] device [pio-mode nnn]

       blktool [options] device [pm-mode nnn]

       blktool [options] device [queue-depth nnn]

       blktool [options] device [read-ahead nnn]

       blktool [options] device [readonly off|on]

       blktool [options] device [reread-part]

       blktool [options] device [reset]

       blktool [options] device [sector-sz]

       blktool [options] device [sleep]

       blktool [options] device [standby]

       blktool [options] device [unmask-irq off|on]

       blktool [options] device [version]

       blktool [options] [version]

       blktool [options] device [wcache off|on]

DESCRIPTION

       blktool is used for querying and/or changing settings of a block device.

       device is the name of the block device to query or modify.

OPTIONS

       -f     For a few commands, blktool will flush the buffers of the block device out to disk,
              before performing the requested command.  Specify this  option,  "force",  disables
              any flushing blktool would attempt to do.

       -t class
              where  class  is  one  of  'ide',  'ata',  'scsi', 'i2o', or 'auto' to override the
              default auto-detection of device class.

COMMANDS

       acoustic-mgmt
              Query or set underlying device's acoustic level.

       block-sz
              Query or set device block size.

       bus-id Query device bus id.

       bus-state
              Query or set device bus state (0 off, 1 on, 2 tristate)

       class  Query the detected (or overridden, via  -t)  device  class.   Typically  this  will
              result  in  'ATA'  or 'SCSI' for most devices.  Detection is based on device major;
              thus your SATA device may appear as 'SCSI'.

       cd-speed
              Set CD-ROM device speed (in Kbytes/sec).

       defect-mgmt
              Toggle underlying device's defect management (obsolete).

       dev-keep-settings
              Toggle underlying device's revert-to-defaults-on-reset feature.

       dev-read-ahead
              Toggle underlying device's read-ahead feature.

       dma    Toggle DMA data transfer.  Omitting the on/off  argument  will  print  the  current
              state.

       geometry
              Query device geometry (cylinders / heads / sectors / etc.).

       i2o-rcache
              Query or set an I2O block device's read cache.

       i2o-wcache
              Query or set an I2O block device's write cache.

       id     Query IDENTIFY [PACKET] DEVICE data.

       keep-settings
              Keep  settings  across  device resets.  Omitting the on/off argument will print the
              current state.

       media  Lock in (or unlock) a removable device.

       multiple-count
              Set multiple count for use in READ/WRITE MULTIPLE commands.

       no-write-err
              Toggle ignore-write-errors flag.  Omitting  the  on/off  argument  will  print  the
              current state.

       pio-data
              ATA  PIO data transfer via 16-bit or 32-bit I/O.  Omitting the on/off argument will
              print the current state.

       pio-mode
              Set underlying ATA device's PIO data transfer mode.

       pm-mode
              Set underlying device's Advanced Power Management mode.

       queued-depth
              Query or set underlying device's queue depth.

       read-ahead
              Query or set block device read-ahead (in units of sectors).

       readonly
              Toggle block device read-only setting.  Omitting the on/off argument will print the
              current state.

       reread-part
              Re-read partition table.

       reset  Execute device reset.

       sector-sz
              Query device sector size.

       sleep  Put device to sleep immediately.

       standby
              Put device in standby mode.

       unmask-irq
              Toggle unmasked irqs.  Omitting the on/off argument will print the current state.

       version
              Print version number and exit.

       wcache Toggle underlying device's writeback cache.

BUGS

       Inevitably there are some.  Please report any you find.

AUTHOR

       blktool was written by Jeff Garzik.

AVAILABILITY

       blktool    is    available    over    the    Web    on    the    SourceForge    site    at
       http://sourceforge.net/projects/gkernel/