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SMARTCTL(8)			  2011-10-20			   SMARTCTL(8)

NAME
       smartctl - Control and Monitor Utility for SMART Disks

SYNOPSIS
       smartctl [options] device

FULL PATH
       /usr/sbin/smartctl

PACKAGE VERSION
       smartmontools-5.42 2011-10-20 r3458

DESCRIPTION
       [This man page is generated for the Linux version of smartmontools.  It
       does not contain info specific to other platforms.]

       smartctl controls the Self-Monitoring, Analysis and Reporting  Technol‐
       ogy  (SMART) system built into many ATA-3 and later ATA, IDE and SCSI-3
       hard drives. The purpose of SMART is to monitor the reliability of  the
       hard drive and predict drive failures, and to carry out different types
       of drive self-tests.  This  version  of	smartctl  is  compatible  with
       ATA/ATAPI-7 and earlier standards (see REFERENCES below)

       smartctl is a command line utility designed to perform SMART tasks such
       as printing the SMART self-test and error logs, enabling and  disabling
       SMART automatic testing, and initiating device self-tests. Note: if the
       user issues a SMART command that is (apparently) not implemented by the
       device,	smartctl  will	print  a warning message but issue the command
       anyway (see the -T, --tolerance option below).  This should  not	 cause
       problems:  on  most  devices,  unimplemented SMART commands issued to a
       drive are ignored and/or return an error.

       smartctl also provides support for polling TapeAlert messages from SCSI
       tape drives and changers.

       The  user  must	specify the device to be controlled or interrogated as
       the final argument to smartctl. The command set used by the  device  is
       often  derived  from  the  device  path but may need help with the ´-d´
       option (for more information see the section on "ATA, SCSI command sets
       and SAT" below). Device paths are as follows:

       LINUX:	Use   the   forms  "/dev/hd[a-t]"  for	IDE/ATA	 devices,  and
		"/dev/sd[a-z]" for SCSI devices.  For  SCSI  Tape  Drives  and
		Changers  with	TapeAlert  support use the devices "/dev/nst*"
		and "/dev/sg*".	 For SATA  disks  accessed  with  libata,  use
		"/dev/sd[a-z]"	and  append  "-d  ata". For disks behind 3ware
		controllers you may need  "/dev/sd[a-z]"  or  "/dev/twe[0-9]",
		"/dev/twa[0-9]"	 or  "/dev/twl[0-9]":  see  details below. For
		disks behind HighPoint RocketRAID  controllers	you  may  need
		"/dev/sd[a-z]".	 For disks behind Areca SATA RAID controllers,
		you need "/dev/sg[2-9]"	 (note	that  smartmontools  interacts
		with  the Areca controllers via a SCSI generic device which is
		different than the SCSI device used for	 reading  and  writing
		data)!

       if  ´-´	is specified as the device path, smartctl reads and interprets
       it's own debug output from standard input.  See ´-r ataioctl´ below for
       details.

       Based  on  the device path, smartctl will guess the device type (ATA or
       SCSI).  If necessary, the ´-d´ option can be  used  to  over-ride  this
       guess

       Note that the printed output of smartctl displays most numerical values
       in base 10 (decimal), but some values are displayed in base  16	(hexa‐
       decimal).  To distinguish them, the base 16 values are always displayed
       with a leading "0x", for example: "0xff". This  man  page  follows  the
       same convention.

OPTIONS
       The  options  are grouped below into several categories.	 smartctl will
       execute	the  corresponding  commands  in   the	 order:	  INFORMATION,
       ENABLE/DISABLE, DISPLAY DATA, RUN/ABORT TESTS.

       SHOW INFORMATION OPTIONS:

       -h, --help, --usage
	      Prints a usage message to STDOUT and exits.

       -V, --version, --copyright, --license
	      Prints  version,	copyright, license, home page and SVN revision
	      information for your copy of smartctl to STDOUT and then	exits.
	      Please  include  this  information  if you are reporting bugs or
	      problems.

       -i, --info
	      Prints the device model number, serial number, firmware version,
	      and  ATA	Standard  version/revision  information.   Says if the
	      device supports SMART, and if so, whether SMART support is  cur‐
	      rently  enabled  or  disabled.   If  the device supports Logical
	      Block Address mode (LBA mode) print current user drive  capacity
	      in bytes. (If drive is has a user protected area reserved, or is
	      "clipped", this may be smaller than the potential maximum	 drive
	      capacity.)  Indicates if the drive is in the smartmontools data‐
	      base (see ´-v´ options below).  If so, the  drive	 model	family
	      may also be printed. If ´-n´ (see below) is specified, the power
	      mode of the drive is printed.

       -a, --all
	      Prints all SMART information about the disk, or TapeAlert infor‐
	      mation about the tape drive or changer.  For ATA devices this is
	      equivalent to
	      ´-H -i -c -A -l error -l selftest -l selective´
	      and for SCSI, this is equivalent to
	      ´-H -i -A -l error -l selftest´.
	      Note that for ATA disks  this  does  not	enable	the  non-SMART
	      options  and  the SMART options which require support for 48-bit
	      ATA commands.

       -x, --xall
	      Prints all SMART and non-SMART information about the device. For
	      ATA devices this is equivalent to
	      ´-H -i -c -A -f brief -l xerror,error -l xselftest,selftest
	      -l selective -l directory -l scttemp -l scterc -l sataphy´.
	      and for SCSI, this is equivalent to
	      ´-H -i -A -l error -l selftest -l background -l sasphy´.

       --scan Scans  for  devices and prints each device name, device type and
	      protocol ([ATA] or [SCSI]) info.	May  be	 used  in  conjunction
	      with  ´-d	 TYPE´	to  restrict the scan to a specific TYPE.  See
	      also info about platform specific device scan and the DEVICESCAN
	      directive on smartd(8) man page.

       --scan-open
	      Same as --scan, but also tries to open each device before print‐
	      ing device info.	The device open may change the device type due
	      to autodetection (see also ´-d test´).

	      This option can be used to create a draft smartd.conf file.  All
	      options after ´--´ are appended to each output line.  For	 exam‐
	      ple:
	      smartctl --scan-open -- -a -W 4,45,50 -m admin@work > smartd.conf

       RUN-TIME BEHAVIOR OPTIONS:

       -q TYPE, --quietmode=TYPE
	      Specifies that smartctl should run in one of the two quiet modes
	      described here.  The valid arguments to this option are:

	      errorsonly - only print: For the ´-l error´ option, if  nonzero,
	      the  number  of  errors  recorded in the SMART error log and the
	      power-on time when they occurred; For the ´-l selftest´  option,
	      errors  recorded	in  the	 device	 self-test  log;  For the ´-H´
	      option,  SMART  "disk  failing"  status  or  device   Attributes
	      (pre-failure  or	usage) which failed either now or in the past;
	      For the ´-A´ option, device Attributes  (pre-failure  or	usage)
	      which failed either now or in the past.

	      silent  - print no output.  The only way to learn about what was
	      found is to use the exit status of smartctl (see	RETURN	VALUES
	      below).

	      noserial - Do not print the serial number of the device.

       -d TYPE, --device=TYPE
	      Specifies	 the  type of the device.  The valid arguments to this
	      option are:

	      auto - attempt to guess the device type from the device name  or
	      from  controller	type  info provided by the operating system or
	      from a matching USB ID entry in the drive database.  This is the
	      default.

	      test - prints the guessed type, then opens the device and prints
	      the (possibly changed) TYPE name and then	 exists	 without  per‐
	      forming any further commands.

	      ata - the device type is ATA.  This prevents smartctl from issu‐
	      ing SCSI commands to an ATA device.

	      scsi - the device type is SCSI.	This  prevents	smartctl  from
	      issuing ATA commands to a SCSI device.

	      sat - the device type is SCSI to ATA Translation (SAT).  This is
	      for ATA disks that have a SCSI to ATA  Translation  (SAT)	 Layer
	      (SATL)  between  the disk and the operating system.  SAT defines
	      two ATA PASS THROUGH SCSI commands, one 12 bytes	long  and  the
	      other  16	 bytes long.  The default is the 16 byte variant which
	      can be overridden with either ´-d sat,12´ or ´-d sat,16´.

	      usbcypress - this device type is for ATA disks that are behind a
	      Cypress USB to PATA bridge.  This will use the ATACB proprietary
	      scsi pass through command.  The default SCSI operation  code  is
	      0x24,  but  although  it	can  be	 overridden  with  ´-d	usbcy‐
	      press,0xN´, where N is the scsi operation code,  you're  running
	      the risk of damage to the device or filesystems on it.

	      usbjmicron  - this device type is for SATA disks that are behind
	      a JMicron USB to PATA/SATA  bridge.   The	 48-bit	 ATA  commands
	      (required	 e.g. for ´-l xerror´, see below) do not work with all
	      of these bridges and are therefore disabled by  default.	 These
	      commands	can be enabled by ´-d usbjmicron,x´.  If two disks are
	      connected to a bridge  with  two	ports,	an  error  message  is
	      printed  if  no PORT is specified.  The port can be specified by
	      ´-d usbjmicron[,x],PORT´ where PORT is 0 (master) or 1  (slave).
	      This  is	not  necessary if the device uses a port multiplier to
	      connect multiple disks to one port.  The disks appear under sep‐
	      arate  /dev/ice  names  then.   CAUTION:	Specifying  ´,x´ for a
	      device which does not support it results in I/O errors  and  may
	      disconnect  the  drive.	The same applies if the specified PORT
	      does not exist or is not connected to a disk.

	      usbsunplus - this device type is for SATA disks that are	behind
	      a SunplusIT USB to SATA bridge.

	      marvell  -  [Linux only] interact with SATA disks behind Marvell
	      chip-set controllers  (using  the	 Marvell  rather  than	libata
	      driver).

	      megaraid,N  -  [Linux  only]  the device consists of one or more
	      SCSI/SAS disks connected to a MegaRAID controller.  The non-neg‐
	      ative  integer  N	 (in  the range of 0 to 127 inclusive) denotes
	      which disk on the controller is monitored.  Use syntax such as:
	      smartctl -a -d megaraid,2 /dev/sda
	      smartctl -a -d megaraid,0 /dev/sdb
	      This interface will also work for Dell  PERC  controllers.   The
	      following /dev/XXX entry must exist:
	      For PERC2/3/4 controllers: /dev/megadev0
	      For PERC5/6 controllers: /dev/megaraid_sas_ioctl_node

	      3ware,N - [FreeBSD and Linux only] the device consists of one or
	      more ATA disks connected to a 3ware RAID controller.   The  non-
	      negative	integer	 N  (in	 the  range  from  0 to 127 inclusive)
	      denotes which disk on the controller is monitored.   Use	syntax
	      such as:
	      smartctl -a -d 3ware,2 /dev/sda
	      smartctl -a -d 3ware,0 /dev/twe0
	      smartctl -a -d 3ware,1 /dev/twa0
	      smartctl -a -d 3ware,1 /dev/twl0
	      The  first  two  forms,  which  refer  to devices /dev/sda-z and
	      /dev/twe0-15, may be used with 3ware series 6000, 7000, and 8000
	      series  controllers  that use the 3x-xxxx driver.	 Note that the
	      /dev/sda-z form is deprecated starting with the Linux 2.6 kernel
	      series  and may not be supported by the Linux kernel in the near
	      future.  The final form, which refers to	devices	 /dev/twa0-15,
	      must  be	used with 3ware 9000 series controllers, which use the
	      3w-9xxx driver.

	      The devices /dev/twl0-15 must be used with  the  3ware/LSI  9750
	      series controllers which use the 3w-sas driver.

	      Note  that  if  the  special  character  device nodes /dev/twl?,
	      /dev/twa?	 and /dev/twe? do not exist, or exist with the	incor‐
	      rect  major or minor numbers, smartctl will recreate them on the
	      fly.  Typically /dev/twa0 refers to the first  9000-series  con‐
	      troller,	/dev/twa1 refers to the second 9000 series controller,
	      and so on.  The /dev/twl0	 devices  refers  to  the  first  9750
	      series  controller,  /dev/twl1 resfers to the second 9750 series
	      controller, and so on.  Likewise /dev/twe0 refers to  the	 first
	      6/7/8000-series  controller,  /dev/twe1  refers  to  the	second
	      6/7/8000 series controller, and so on.

	      Note that for the 6/7/8000  controllers,	any  of	 the  physical
	      disks  can  be queried or examined using any of the 3ware's SCSI
	      logical device  /dev/sd?	 entries.   Thus,  if  logical	device
	      /dev/sda	is made up of two physical disks (3ware ports zero and
	      one) and logical device /dev/sdb is made up of two other	physi‐
	      cal  disks  (3ware ports two and three) then you can examine the
	      SMART data on any of the four physical disks using  either  SCSI
	      device  /dev/sda or /dev/sdb.  If you need to know which logical
	      SCSI device a particular physical disk (3ware port)  is  associ‐
	      ated  with, use the dmesg or SYSLOG output to show which SCSI ID
	      corresponds to a particular 3ware unit, and then use  the	 3ware
	      CLI or 3dm tool to determine which ports (physical disks) corre‐
	      spond to particular 3ware units.

	      If the value of N corresponds to a port that does not  exist  on
	      the 3ware controller, or to a port that does not physically have
	      a disk attached to it, the behavior of smartctl depends upon the
	      specific	controller model, firmware, Linux kernel and platform.
	      In some cases you will get a warning  message  that  the	device
	      does  not	 exist.	  In  other  cases  you will be presented with
	      ´void´ data for a non-existent device.

	      Note that if the /dev/sd? addressing form is  used,  then	 older
	      3w-xxxx  drivers do not pass the "Enable Autosave" (´-S on´) and
	      "Enable Automatic Offline" (´-o on´) commands to the  disk,  and
	      produce  these  types of harmless syslog error messages instead:
	      "3w-xxxx: tw_ioctl(): Passthru size (123392) too big".  This can
	      be  fixed	 by  upgrading	to version 1.02.00.037 or later of the
	      3w-xxxx driver, or  by  applying	a  patch  to  older  versions.
	      Alternatively, use the character device /dev/twe0-15 interface.

	      The  selective  self-test	 functions  (´-t select,A-B´) are only
	      supported using the  character  device  interface	 /dev/twl0-15,
	      /dev/twa0-15 and /dev/twe0-15.  The necessary WRITE LOG commands
	      can not be passed through the SCSI interface.

	      areca,N - [Linux only] the device consists of one or  more  SATA
	      disks  connected to an Areca SATA RAID controller.  The positive
	      integer N (in the range from 1 to 24  inclusive)	denotes	 which
	      disk on the controller is monitored.  Use syntax such as:
	      smartctl -a -d areca,2 /dev/sg2
	      smartctl -a -d areca,3 /dev/sg3
	      The  first  line	above  addresses  the second disk on the first
	      Areca RAID controller.  The second line addresses the third disk
	      on  the second Areca RAID controller.  To help identify the cor‐
	      rect device, use the command:
	      cat /proc/scsi/sg/device_hdr /proc/scsi/sg/devices
	      to show the SCSI generic devices (one per	 line,	starting  with
	      /dev/sg0).   The	correct	 SCSI  generic	devices to address for
	      smartmontools are the ones with the type field equal to  3.   If
	      the incorrect device is addressed, please read the warning/error
	      messages	carefully.   They  should  provide  hints  about  what
	      devices to use.

	      Important:  the Areca controller must have firmware version 1.46
	      or later.	 Lower-numbered firmware versions will give (harmless)
	      SCSI error messages and no SMART information.

	      cciss,N - [FreeBSD and Linux only] the device consists of one or
	      more SCSI/SAS disks connected to a cciss RAID  controller.   The
	      non-negative  integer  N	(in  the range from 0 to 15 inclusive)
	      denotes which disk on the controller is monitored.

	      If the controller firmware or driver provides a SAT Layer it may
	      be  possible  to	monitor	 also  SATA  disks  by specifiying ´-d
	      sat+cciss,N´.

	      hpt,L/M/N - [FreeBSD and Linux only] the device consists of  one
	      or  more	ATA  disks  connected  to  a HighPoint RocketRAID con‐
	      troller.	The integer L is the controller id, the integer	 M  is
	      the channel number, and the integer N is the PMPort number if it
	      is available.  The allowed values of L are from 1	 to  4	inclu‐
	      sive,  M	are from 1 to 16 inclusive and N from 1 to 4 if PMPort
	      available.  And also these values are limited by	the  model  of
	      the HighPoint RocketRAID controller.  Use syntax such as:
	      smartctl -a -d hpt,1/3 /dev/sda	 (under Linux)
	      smartctl -a -d hpt,1/2/3 /dev/sda	   (under Linux)
	      Note  that  the  /dev/sda-z form should be the device node which
	      stands for the disks derived from the HighPoint RocketRAID  con‐
	      trollers	under  Linux  and  under  FreeBSD, it is the character
	      device   which   the   driver   registered   (eg,	   /dev/hptrr,
	      /dev/hptmv6).

       -T TYPE, --tolerance=TYPE
	      [ATA  only] Specifies how tolerant smartctl should be of ATA and
	      SMART command failures.

	      The behavior of smartctl depends upon  whether  the  command  is
	      "optional"  or  "mandatory". Here "mandatory" means "required by
	      the ATA/ATAPI-5 Specification if the device implements the SMART
	      command	set"   and  "optional"	means  "not  required  by  the
	      ATA/ATAPI-5 Specification even  if  the  device  implements  the
	      SMART command set."  The "mandatory" ATA and SMART commands are:
	      (1) ATA IDENTIFY	DEVICE,	 (2)  SMART  ENABLE/DISABLE  ATTRIBUTE
	      AUTOSAVE, (3) SMART ENABLE/DISABLE, and (4) SMART RETURN STATUS.

	      The valid arguments to this option are:

	      normal  -	 exit  on  failure of any mandatory SMART command, and
	      ignore all failures of optional SMART  commands.	 This  is  the
	      default.	 Note  that  on	 some  devices,	 issuing unimplemented
	      optional SMART commands doesn´t cause an error.  This can result
	      in  misleading  smartctl	messages such as "Feature X not imple‐
	      mented", followed shortly by "Feature X: enabled".  In most such
	      cases, contrary to the final message, Feature X is not enabled.

	      conservative - exit on failure of any optional SMART command.

	      permissive  -  ignore  failure(s)	 of  mandatory SMART commands.
	      This option may be given more than once.	Each additional use of
	      this  option  will  cause	 one  more  additional	failure	 to be
	      ignored.	Note that the use of this option can lead to  messages
	      like  "Feature  X	 not implemented", followed shortly by "Error:
	      unable to enable Feature X".  In a few such cases,  contrary  to
	      the final message, Feature X is enabled.

	      verypermissive - equivalent to giving a large number of ´-T per‐
	      missive´ options: ignore failures of  any	 number	 of  mandatory
	      SMART commands.  Please see the note above.

       -b TYPE, --badsum=TYPE
	      [ATA only] Specifies the action smartctl should take if a check‐
	      sum error is detected in the: (1) Device Identity Structure, (2)
	      SMART  Self-Test Log Structure, (3) SMART Attribute Value Struc‐
	      ture, (4) SMART Attribute Threshold Structure, or (5) ATA	 Error
	      Log Structure.

	      The valid arguments to this option are:

	      warn  -  report  the incorrect checksum but carry on in spite of
	      it.  This is the default.

	      exit - exit smartctl.

	      ignore - continue silently without issuing a warning.

       -r TYPE, --report=TYPE
	      Intended primarily to help smartmontools	developers  understand
	      the  behavior  of smartmontools on non-conforming or poorly con‐
	      forming hardware.	  This	option	reports	 details  of  smartctl
	      transactions  with  the device.  The option can be used multiple
	      times.  When used just once, it shows a record  of  the  ioctl()
	      transactions  with  the  device.	 When used more than once, the
	      detail of these ioctl() transactions  are	 reported  in  greater
	      detail.  The valid arguments to this option are:

	      ioctl - report all ioctl() transactions.

	      ataioctl - report only ioctl() transactions with ATA devices.

	      scsiioctl	 - report only ioctl() transactions with SCSI devices.
	      Invoking this once shows the SCSI commands in hex and the corre‐
	      sponding status. Invoking it a second time adds a hex listing of
	      the first 64 bytes of data send to, or received from the device.

	      Any argument may include a positive integer to specify the level
	      of  detail that should be reported.  The argument should be fol‐
	      lowed by a comma then the integer with no spaces.	 For  example,
	      ataioctl,2  The  default	level is 1, so ´-r ataioctl,1´ and ´-r
	      ataioctl´ are equivalent.

	      For testing purposes, the output of ´-r ataioctl,2´ can later be
	      parsed  by  smartctl  itself if ´-´ is used as device path argu‐
	      ment.  The ATA command input parameters, sector data and	return
	      values  are reconstructed from the debug report read from stdin.
	      Then smartctl internally simulates an ATA device with  the  same
	      behaviour. This is does not work for SCSI devices yet.

       -n POWERMODE, --nocheck=POWERMODE
	      [ATA  only]  Specifies if smartctl should exit before performing
	      any checks when the device is in a low-power  mode.  It  may  be
	      used to prevent a disk from being spun-up by smartctl. The power
	      mode is ignored by default.  A nonzero exit status  is  returned
	      if  the  device  is in one of the specified low-power modes (see
	      RETURN VALUES below).

	      Note: If this option is used it may also be necessary to specify
	      the  device type with the ´-d´ option.  Otherwise the device may
	      spin up due to commands issued during device type autodetection.

	      The valid arguments to this option are:

	      never - check the device always, but print  the  power  mode  if
	      ´-i´ is specified.

	      sleep - check the device unless it is in SLEEP mode.

	      standby  -  check	 the  device  unless it is in SLEEP or STANDBY
	      mode.  In these modes most disks are not	spinning,  so  if  you
	      want  to	prevent a disk from spinning up, this is probably what
	      you want.

	      idle - check the device unless it is in SLEEP, STANDBY  or  IDLE
	      mode.  In the IDLE state, most disks are still spinning, so this
	      is probably not what you want.

       SMART FEATURE ENABLE/DISABLE COMMANDS:

	      Note: if multiple options are used to both enable and disable  a
	      feature,	then  both  the	 enable	 and  disable commands will be
	      issued.  The enable command will always  be  issued  before  the
	      corresponding disable command.

       -s VALUE, --smart=VALUE
	      Enables  or  disables  SMART  on device.	The valid arguments to
	      this option are on and off.  Note that the command ´-s on´ (per‐
	      haps  used  with with the ´-o on´ and ´-S on´ options) should be
	      placed in a start-up script for your  machine,  for  example  in
	      rc.local	or rc.sysinit. In principle the SMART feature settings
	      are preserved over power-cycling, but  it	 doesn´t  hurt	to  be
	      sure. It is not necessary (or useful) to enable SMART to see the
	      TapeAlert messages.

       -o VALUE, --offlineauto=VALUE
	      [ATA only] Enables or disables  SMART  automatic	offline	 test,
	      which  scans  the	 drive every four hours for disk defects. This
	      command can be given during normal system operation.  The	 valid
	      arguments to this option are on and off.

	      Note  that the SMART automatic offline test command is listed as
	      "Obsolete" in every version of the ATA and ATA/ATAPI  Specifica‐
	      tions.   It  was	originally  part of the SFF-8035i Revision 2.0
	      specification, but was never  part  of  any  ATA	specification.
	      However  it is implemented and used by many vendors. [Good docu‐
	      mentation can be found in IBM´s Official Published Disk Specifi‐
	      cations.	 For  example the IBM Travelstar 40GNX Hard Disk Drive
	      Specifications (Revision 1.1, 22 April 2002, Publication # 1541,
	      Document S07N-7715-02) page 164. You can also read the SFF-8035i
	      Specification -- see REFERENCES below.]  You can tell  if	 auto‐
	      matic  offline  testing  is  supported by seeing if this command
	      enables and disables it, as indicated by the ´Auto Offline  Data
	      Collection´  part	 of  the  SMART capabilities report (displayed
	      with ´-c´).

	      SMART provides three basic categories  of	 testing.   The	 first
	      category,	 called "online" testing, has no effect on the perfor‐
	      mance of the device.  It is turned on by the ´-s on´ option.

	      The second category of testing is called "offline" testing. This
	      type  of test can, in principle, degrade the device performance.
	      The ´-o on´ option causes this offline  testing  to  be  carried
	      out, automatically, on a regular scheduled basis.	 Normally, the
	      disk will suspend offline testing while disk accesses are taking
	      place, and then automatically resume it when the disk would oth‐
	      erwise be idle, so in practice it has little effect.  Note  that
	      a one-time offline test can also be carried out immediately upon
	      receipt of a user command.  See the ´-t offline´	option	below,
	      which  causes  a one-time offline test to be carried out immedi‐
	      ately.

	      The choice (made by the SFF-8035i and ATA specification authors)
	      of  the  word testing for these first two categories is unfortu‐
	      nate, and often leads to confusion.  In  fact  these  first  two
	      categories  of  online  and offline testing could have been more
	      accurately described as online and offline data collection.

	      The results of this automatic or immediate offline testing (data
	      collection) are reflected in the values of the SMART Attributes.
	      Thus, if problems or errors are detected, the  values  of	 these
	      Attributes will go below their failure thresholds; some types of
	      errors may also appear in the SMART error log. These are visible
	      with the ´-A´ and ´-l error´ options respectively.

	      Some  SMART  attribute  values  are updated only during off-line
	      data collection activities; the rest are updated	during	normal
	      operation	 of  the  device  or  during both normal operation and
	      off-line testing.	 The Attribute value  table  produced  by  the
	      ´-A´ option indicates this in the UPDATED column.	 Attributes of
	      the first type are labeled "Offline" and Attributes of the  sec‐
	      ond type are labeled "Always".

	      The  third  category of testing (and the only category for which
	      the word ´testing´ is really an appropriate  choice)  is	"self"
	      testing.	 This  third  type  of test is only performed (immedi‐
	      ately) when a command to run it is issued.  The  ´-t´  and  ´-X´
	      options  can  be	used  to  carry out and abort such self-tests;
	      please see below for further details.

	      Any errors detected in the self testing will  be	shown  in  the
	      SMART  self-test	log, which can be examined using the ´-l self‐
	      test´ option.

	      Note: in this manual page, the word "Test" is used in connection
	      with  the second category just described, e.g. for the "offline"
	      testing.	The words "Self-test" are used in connection with  the
	      third category.

       -S VALUE, --saveauto=VALUE
	      [ATA]  Enables  or disables SMART autosave of device vendor-spe‐
	      cific Attributes. The valid arguments to this option are on  and
	      off.   Note  that	 this  feature	is preserved across disk power
	      cycles, so you should only need to issue it once.

	      The ATA standard does not specify	 a  method  to	check  whether
	      SMART  autosave  is  enabled.  Unlike  SCSI (below), smartctl is
	      unable to print a warning if autosave is disabled.

	      [SCSI] For SCSI devices this toggles the	value  of  the	Global
	      Logging  Target  Save  Disabled  (GLTSD) bit in the Control Mode
	      Page. Some disk manufacturers set this bit by default. This pre‐
	      vents  error counters, power-up hours and other useful data from
	      being placed in non-volatile storage, so	these  values  may  be
	      reset  to zero the next time the device is power-cycled.	If the
	      GLTSD bit is set then ´smartctl -a´ will issue a warning. Use on
	      to  clear	 the  GLTSD  bit  and  thus  enable saving counters to
	      non-volatile storage. For extreme streaming-video type  applica‐
	      tions you might consider using off to set the GLTSD bit.

       SMART READ AND DISPLAY DATA OPTIONS:

       -H, --health
	      Check: Ask the device to report its SMART health status or pend‐
	      ing TapeAlert messages.  SMART status is	based  on  information
	      that  it	has gathered from online and offline tests, which were
	      used to determine/update	its  SMART  vendor-specific  Attribute
	      values.  TapeAlert  status  is obtained by reading the TapeAlert
	      log page.

	      If the device reports failing health status, this	 means	either
	      that the device has already failed, or that it is predicting its
	      own failure within the next 24 hours.  If this happens, use  the
	      ´-a´  option  to get more information, and get your data off the
	      disk and to someplace safe as soon as you can.

       -c, --capabilities
	      [ATA only] Prints only the generic  SMART	 capabilities.	 These
	      show what SMART features are implemented and how the device will
	      respond to some of the different SMART commands.	For example it
	      shows  if the device logs errors, if it supports offline surface
	      scanning, and so on.  If the device can  carry  out  self-tests,
	      this  option also shows the estimated time required to run those
	      tests.

	      Note that the time required to run  the  Self-tests  (listed  in
	      minutes)	are fixed.  However the time required to run the Imme‐
	      diate Offline Test (listed in seconds) is variable.  This	 means
	      that if you issue a command to perform an Immediate Offline test
	      with the ´-t offline´ option, then the time may jump to a larger
	      value  and then count down as the Immediate Offline Test is car‐
	      ried out.	 Please see REFERENCES below for  further  information
	      about the the flags and capabilities described by this option.

       -A, --attributes
	      [ATA]  Prints  only  the	vendor specific SMART Attributes.  The
	      Attributes are numbered from 1 to 253 and	 have  specific	 names
	      and ID numbers. For example Attribute 12 is "power cycle count":
	      how many times has the disk been powered up.

	      Each Attribute has a "Raw"  value,  printed  under  the  heading
	      "RAW_VALUE",  and a "Normalized" value printed under the heading
	      "VALUE".	[Note: smartctl prints these values in	base-10.]   In
	      the  example  just given, the "Raw Value" for Attribute 12 would
	      be  the  actual  number  of  times  that	the  disk   has	  been
	      power-cycled,  for  example  365	if the disk has been turned on
	      once per day for exactly one year.  Each vendor uses  their  own
	      algorithm to convert this "Raw" value to a "Normalized" value in
	      the range from 1 to 254.	Please keep in mind that smartctl only
	      reports the different Attribute types, values, and thresholds as
	      read from the device.  It does  not  carry  out  the  conversion
	      between  "Raw"  and  "Normalized"	 values:  this	is done by the
	      disk´s firmware.

	      The conversion from Raw value to a quantity with physical	 units
	      is  not specified by the SMART standard. In most cases, the val‐
	      ues printed by smartctl are sensible.  For example the  tempera‐
	      ture Attribute generally has its raw value equal to the tempera‐
	      ture in Celsius.	However in some cases vendors use unusual con‐
	      ventions.	 For example the Hitachi disk on my laptop reports its
	      power-on hours in minutes, not hours. Some IBM disks track three
	      temperatures rather than one, in their raw values.  And so on.

	      Each  Attribute  also has a Threshold value (whose range is 0 to
	      255) which is printed under the heading "THRESH".	 If  the  Nor‐
	      malized value is less than or equal to the Threshold value, then
	      the Attribute is said to have failed.  If	 the  Attribute	 is  a
	      pre-failure Attribute, then disk failure is imminent.

	      Each  Attribute also has a "Worst" value shown under the heading
	      "WORST".	This is the smallest (closest to failure)  value  that
	      the disk has recorded at any time during its lifetime when SMART
	      was enabled.  [Note however that some vendors firmware may actu‐
	      ally   increase	the   "Worst"	value	for  some  "rate-type"
	      Attributes.]

	      The Attribute table printed  out	by  smartctl  also  shows  the
	      "TYPE"  of  the  Attribute.  Attributes  are one of two possible
	      types: Pre-failure or Old age.  Pre-failure Attributes are  ones
	      which, if less than or equal to their threshold values, indicate
	      pending disk failure.  Old age, or usage	Attributes,  are  ones
	      which  indicate end-of-product life from old-age or normal aging
	      and wearout, if the Attribute value is less than or equal to the
	      threshold.   Please  note: the fact that an Attribute is of type
	      'Pre-fail' does not mean that your disk is about	to  fail!   It
	      only  has	 this  meaning	if  the Attribute´s current Normalized
	      value is less than or equal to the threshold value.

	      If the Attribute´s current Normalized  value  is	less  than  or
	      equal to the threshold value, then the "WHEN_FAILED" column will
	      display "FAILING_NOW". If not, but the worst recorded  value  is
	      less than or equal to the threshold value, then this column will
	      display "In_the_past".  If the "WHEN_FAILED" column has no entry
	      (indicated  by  a	 dash: ´-´) then this Attribute is OK now (not
	      failing) and has also never failed in the past.

	      The table column labeled "UPDATED" shows if the SMART  Attribute
	      values  are  updated  during  both normal operation and off-line
	      testing, or only during offline testing.	The former are labeled
	      "Always" and the latter are labeled "Offline".

	      So  to  summarize:  the  Raw  Attribute values are the ones that
	      might have a real physical interpretation, such as  "Temperature
	      Celsius",	 "Hours",  or  "Start-Stop Cycles".  Each manufacturer
	      converts these, using their detailed  knowledge  of  the	disk´s
	      operations  and failure modes, to Normalized Attribute values in
	      the range 1-254.	The current and	 worst	(lowest	 measured)  of
	      these  Normalized Attribute values are stored on the disk, along
	      with a Threshold value that the manufacturer has determined will
	      indicate that the disk is going to fail, or that it has exceeded
	      its design age or aging limit.  smartctl does not calculate  any
	      of the Attribute values, thresholds, or types, it merely reports
	      them from the SMART data on the device.

	      Note that starting with ATA/ATAPI-4, revision 4, the meaning  of
	      these  Attribute	fields has been made entirely vendor-specific.
	      However most ATA/ATAPI-5 disks seem to respect their meaning, so
	      we have retained the option of printing the Attribute values.

	      [SCSI]  For  SCSI devices the "attributes" are obtained from the
	      temperature and start-stop cycle counter log pages. Certain ven‐
	      dor specific attributes are listed if recognised. The attributes
	      are output in a relatively free format (compared with  ATA  disk
	      attributes).

       -f FORMAT, --format=FORMAT
	      [ATA  only]  Selects  the output format of the attributes to one
	      of:

	      old - Old smartctl format. This is the default unless  the  ´-x´
	      option is specified.

	      brief  -	New  format  which fits into 80 colums (except in some
	      rare cases).  This format also decodes four additional attribute
	      flags.  This is the default if the '-x´ option is specified.

       -l TYPE, --log=TYPE
	      Prints  either the SMART Error Log, the SMART Self-Test Log, the
	      SMART Selective Self-Test Log [ATA only], the Log Directory [ATA
	      only],  or  the  Background  Scan	 Results Log [SCSI only].  The
	      valid arguments to this option are:

	      error - [ATA] prints the Summary SMART error log.	  SMART	 disks
	      maintain	a  log of the most recent five non-trivial errors. For
	      each of these errors, the disk power-on lifetime	at  which  the
	      error  occurred  is  recorded,  as  is  the device status (idle,
	      standby, etc) at the time of the error.  For some	 common	 types
	      of errors, the Error Register (ER) and Status Register (SR) val‐
	      ues are decoded and printed as text. The meanings of these are:
		 ABRT:	Command ABoRTed
		 AMNF:	Address Mark Not Found
		 CCTO:	Command Completion Timed Out
		 EOM:	End Of Media
		 ICRC:	Interface Cyclic Redundancy Code (CRC) error
		 IDNF:	IDentity Not Found
		 ILI:	(packet command-set specific)
		 MC:	Media Changed
		 MCR:	Media Change Request
		 NM:	No Media
		 obs:	obsolete
		 TK0NF: TracK 0 Not Found
		 UNC:	UNCorrectable Error in Data
		 WP:	Media is Write Protected
	      In addition, up to the last  five	 commands  that	 preceded  the
	      error are listed, along with a timestamp measured from the start
	      of the corresponding power cycle. This is displayed in the  form
	      Dd+HH:MM:SS.msec	where D is the number of days, HH is hours, MM
	      is minutes, SS is seconds and msec is milliseconds.  [Note: this
	      time  stamp wraps after 2^32 milliseconds, or 49 days 17 hours 2
	      minutes and 47.296 seconds.]  The key  ATA  disk	registers  are
	      also  recorded in the log.  The final column of the error log is
	      a text-string description of the ATA command defined by the Com‐
	      mand  Register  (CR) and Feature Register (FR) values.  Commands
	      that are obsolete in the most current (ATA-7)  spec  are	listed
	      like  this:  READ	 LONG  (w/ retry) [OBS-4], indicating that the
	      command became obsolete with  or	in  the	 ATA-4	specification.
	      Similarly,  the notation [RET-N] is used to indicate that a com‐
	      mand was retired in the ATA-N specification.  Some commands  are
	      not  defined  in any version of the ATA specification but are in
	      common use nonetheless; these are marked [NS], meaning non-stan‐
	      dard.

	      The  ATA	Specification  (ATA-5 Revision 1c, Section 8.41.6.8.2)
	      says: "Error log	structures  shall  include  UNC	 errors,  IDNF
	      errors  for which the address requested was valid, servo errors,
	      write fault errors, etc.	Error log data	structures  shall  not
	      include errors attributed to the receipt of faulty commands such
	      as command codes not implemented by the device or requests  with
	      invalid  parameters  or  invalid	addresses." The definitions of
	      these terms are:
	      UNC (UNCorrectable): data is uncorrectable.  This refers to data
	      which  has  been	read  from  the	 disk, but for which the Error
	      Checking	and  Correction	 (ECC)	codes  are  inconsistent.   In
	      effect, this means that the data can not be read.
	      IDNF (ID Not Found): user-accessible address could not be found.
	      For READ LOG type commands, IDNF can also indicate that a device
	      data log structure checksum was incorrect.

	      If  the  command	that caused the error was a READ or WRITE com‐
	      mand, then the Logical Block Address (LBA) at  which  the	 error
	      occurred	will  be printed in base 10 and base 16.  The LBA is a
	      linear address, which  counts  512-byte  sectors	on  the	 disk,
	      starting	from  zero.   (Because of the limitations of the SMART
	      error log, if the LBA is greater than 0xfffffff, then either  no
	      error  log  entry will be made, or the error log entry will have
	      an incorrect LBA. This may happen for  drives  with  a  capacity
	      greater  than 128 GiB or 137 GB.) On Linux systems the smartmon‐
	      tools web page has instructions about how	 to  convert  the  LBA
	      address  to  the	name of the disk file containing the erroneous
	      disk sector.

	      Please note that some manufacturers ignore  the  ATA  specifica‐
	      tions,  and make entries in the error log if the device receives
	      a command which is not implemented or is not valid.

	      error - [SCSI] prints the error counter  log  pages  for	reads,
	      write  and verifies.  The verify row is only output if it has an
	      element other than zero.

	      xerror[,NUM][,error] - [ATA only] prints the Extended Comprehen‐
	      sive SMART error log (General Purpose Log address 0x03).	Unlike
	      the Summary SMART error log (see ´-l error´ above), it  provides
	      sufficient  space to log the contents of the 48-bit LBA register
	      set introduced with ATA-6.  It also supports logs with more than
	      one  sector.   Each sector holds up to 4 log entries. The actual
	      number of log sectors is vendor specific, typical values for HDD
	      are 2 (Samsung), 5 (Seagate) or 6 (WD).  Some recent SSD devices
	      have much larger error logs.

	      Only the 8 most recent error log entries are printed by default.
	      This number can be changed by the optional parameter NUM.

	      If  ',error'  is	appended  and the Extended Comprehensive SMART
	      error log is not supported, the Summary SMART self-test  log  is
	      printed.

	      Please note that some recent (e.g. Samsung) drives report errors
	      only in the Extended Comprehensive SMART error log. The  Summary
	      SMART error log can be read but is always empty.

	      selftest - [ATA] prints the SMART self-test log.	The disk main‐
	      tains a self-test log showing the results	 of  the  self	tests,
	      which  can  be  run  using the ´-t´ option described below.  For
	      each of the most recent twenty-one self-tests, the log shows the
	      type  of	test  (short or extended, off-line or captive) and the
	      final status of the test.	 If the test did not complete success‐
	      fully,  then the percentage of the test remaining is shown.  The
	      time at which the test took place, measured  in  hours  of  disk
	      lifetime,	 is  also  printed. [Note: this time stamp wraps after
	      2^16 hours, or 2730 days and 16 hours, or about 7.5  years.]  If
	      any errors were detected, the Logical Block Address (LBA) of the
	      first error is printed in decimal notation.   On	Linux  systems
	      the smartmontools web page has instructions about how to convert
	      this LBA address to the name of the  disk	 file  containing  the
	      erroneous block.

	      selftest	-  [SCSI]  the	self-test  log for a SCSI device has a
	      slightly different format than for an ATA device.	 For  each  of
	      the most recent twenty self-tests, it shows the type of test and
	      the status (final or in progress) of the	test.  SCSI  standards
	      use  the	terms "foreground" and "background" (rather than ATA´s
	      corresponding "captive" and "off-line") and "short"  and	"long"
	      (rather  than  ATA´s  corresponding  "short"  and "extended") to
	      describe the type of the test.  The printed  segment  number  is
	      only  relevant when a test fails in the third or later test seg‐
	      ment.  It identifies the test that failed and consists of either
	      the  number  of  the segment that failed during the test, or the
	      number of the test that failed and the number of the segment  in
	      which  the  test	was  run,  using  a  vendor-specific method of
	      putting both numbers into a  single  byte.   The	Logical	 Block
	      Address (LBA) of the first error is printed in hexadecimal nota‐
	      tion.  On Linux systems the smartmontools web page has  instruc‐
	      tions  about  how to convert this LBA address to the name of the
	      disk file containing the erroneous block.	 If provided, the SCSI
	      Sense Key (SK), Additional Sense Code (ASC) and Additional Sense
	      Code Qualifier (ASQ) are also printed. The self tests can be run
	      using the ´-t´ option described below (using the ATA test termi‐
	      nology).

	      xselftest[,NUM][,selftest] -  [ATA  only]	 prints	 the  Extended
	      SMART  self-test	log (General Purpose Log address 0x07). Unlike
	      the SMART self-test log (see ´-l selftest´ above),  it  supports
	      48-bit  LBA  and	logs  with  more than one sector.  Each sector
	      holds up to 19 log entries. The actual number of log sectors  is
	      vendor specific, typical values are 1 (Seagate) or 2 (Samsung).

	      Only the 25 most recent log entries are printed by default. This
	      number can be changed by the optional parameter NUM.

	      If ',selftest' is appended and the Extended SMART self-test  log
	      is not supported, the old SMART self-test log is printed.

	      selective	 -  [ATA only] Please see the ´-t select´ option below
	      for  a  description  of  selective  self-tests.	The  selective
	      self-test	 log shows the start/end Logical Block Addresses (LBA)
	      of each of the five test spans, and their current	 test  status.
	      If  the  span  is	 being	tested or the remainder of the disk is
	      being read-scanned, the current 65536-sector block of LBAs being
	      tested  is  also	displayed.   The  selective self-test log also
	      shows if a read-scan of the remainder of the disk will  be  car‐
	      ried  out	 after	the selective self-test has completed (see ´-t
	      afterselect´ option) and the time delay before  restarting  this
	      read-scan	 if  it is interrupted (see ´-t pending´ option). This
	      is a new smartmontools feature; please report unusual or	incor‐
	      rect behavior to the smartmontools-support mailing list.

	      directory[,gs]  -	 [ATA only] if the device supports the General
	      Purpose Logging feature set (ATA-6 and above) then  this	prints
	      the  Log	Directory  (the	 log at address 0).  The Log Directory
	      shows what logs are available and their length in	 sectors  (512
	      bytes).	The  contents  of the logs at address 1 [Summary SMART
	      error log] and at address 6 [SMART self-test log] may be printed
	      using  the  previously-described error and selftest arguments to
	      this option.  If your version of smartctl	 supports  48-bit  ATA
	      commands,	 both the General Purpose Log (GPL) and SMART Log (SL)
	      directories are printed in one combined table. The output can be
	      restricted  to  the  GPL directory or SL directory by ´-l direc‐
	      tory,q´ or ´-l directory,s´ respectively.

	      background - [SCSI only] the background scan results log outputs
	      information derived from Background Media Scans (BMS) done after
	      power up and/or periodocally (e.g. every	24  hours)  on	recent
	      SCSI  disks. If supported, the BMS status is output first, indi‐
	      cating whether a background scan is currently underway  (and  if
	      so  a progress percentage), the amount of time the disk has been
	      powered up and the number of scans already completed. Then there
	      is  a  header and a line for each background scan "event". These
	      will typically be either recovered or unrecoverable errors. That
	      latter  group may need some attention. There is a description of
	      the background scan mechansim in section 4.18 of SBC-3  revision
	      6 (see www.t10.org ).

	      scttemp,	scttempsts,  scttemphist  - [ATA only] prints the disk
	      temperature information provided by the SMART Command  Transport
	      (SCT) commands.  The option ´scttempsts´ prints current tempera‐
	      ture and temperature ranges returned by the SCT Status  command,
	      ´scttemphist´ prints temperature limits and the temperature his‐
	      tory table returned by the SCT Data Table command, and ´scttemp´
	      prints  both.  The temperature values are preserved across power
	      cycles.  The logging interval can be  configured	with  the  ´-l
	      scttempint,N[,p]´	 option,  see  below.	The  SCT commands were
	      introduced in ATA-8 ACS and were also supported by in many ATA-7
	      disks.

	      scttempint,N[,p] - [ATA only] clears the SCT temperature history
	      table and sets the time interval for temperature	logging	 to  N
	      minutes.	 If ´,p´ is specified, the setting is preserved across
	      power cycles.  Otherwise, the setting is volatile	 and  will  be
	      reverted	to  the	 last  non-volatile  setting  by the next hard
	      reset.  The default interval is vendor specific, typical	values
	      are 1, 2, or 5 minutes.

	      scterc[,READTIME,WRITETIME]  -  [ATA  only]  prints  values  and
	      descriptions of the SCT Error Recovery Control  settings.	 These
	      are  equivalent  to  TLER (as used by Western Digital), CCTL (as
	      used by Samsung and Hitachi) and ERC (as used by Seagate). READ‐
	      TIME  and	 WRITETIME  arguments  (deciseconds) set the specified
	      values. Values of 0 disable the feature, other values less  than
	      65  are probably not supported. For RAID configurations, this is
	      typically set to 70,70 deciseconds.

	      devstat[,PAGE] - [ATA only] [NEW EXPERIMENTAL SMARTCTL  FEATURE]
	      prints  values and descriptions of the ATA Device Statistics log
	      pages (General Purpose Log address 0x04).	 If no PAGE number  is
	      specified,  entries  from	 all  supported pages are printed.  If
	      PAGE 0 is specified, the list of	supported  pages  is  printed.
	      Device  Statistics  was introduced in ATA-8 ACS and is only sup‐
	      ported by some recent devices (e.g. Intel	 320  and  710	Series
	      SSDs).

	      sataphy[,reset]  - [SATA only] prints values and descriptions of
	      the SATA Phy Event Counters (General Purpose Log address	0x11).
	      If ´-l sataphy,reset´ is specified, all counters are reset after
	      reading the values.

	      sasphy[,reset] - [SAS (SCSI) only] prints	 values	 and  descrip‐
	      tions  of	 the  SAS  (SSP)  Protocol Specific log page (log page
	      0x18).  If ´-l sasphy,reset´  is	specified,  all	 counters  are
	      reset after reading the values.

	      gplog,ADDR[,FIRST[-LAST|+SIZE]]  -  [ATA only] prints a hex dump
	      of any log accessible via General Purpose Logging (GPL) feature.
	      The log address ADDR is the hex address listed in the log direc‐
	      tory (see ´-l directory´	above).	  The  range  of  log  sectors
	      (pages)  can  be	specified  by  decimal	values	FIRST-LAST  or
	      FIRST+SIZE.  FIRST defaults to 0, SIZE defaults to 1.  LAST  can
	      be set to ´max´ to specify the last page of the log.

	      smartlog,ADDR[,FIRST[-LAST|+SIZE]]  -  [ATA  only]  prints a hex
	      dump of any log accessible via SMART Read Log command.  See  ´-l
	      gplog,...´ above for parameter syntax.

	      For example, all these commands:
		smartctl -l gplog,0x80,10-15 /dev/sda
		smartctl -l gplog,0x80,10+6 /dev/sda
		smartctl -l smartlog,0x80,10-15 /dev/sda
	      print pages 10-15 of log 0x80 (first host vendor specific log).

	      The  hex	dump  format  is compatible with the ´xxd -r´ command.
	      This command:
		smartctl -l gplog,0x11 /dev/sda | grep ^0 | xxd -r >log.bin
	      writes a binary representation of the one sector log 0x11	 (SATA
	      Phy Event Counters) to file log.bin.

	      ssd  -  [ATA] prints the Solid State Device Statistics log page.
	      This has the same effect as ´-l devstat,7´, see above.

	      ssd - [SCSI]  prints  the	 Solid	State  Media  percentage  used
	      endurance	 indicator.  A	value  of 0 indicates as new condition
	      while 100 indicates the device is at the end of its lifetime  as
	      projected by the manufacturer. The value may reach 255.

       -v   ID,FORMAT[:BYTEORDER][,NAME],   --vendorattribute=ID,FORMAT[:BYTE‐
       ORDER][,NAME]
	      [ATA only] Sets a vendor-specific raw  value  print  FORMAT,  an
	      optional	BYTEORDER and an optional NAME for Attribute ID.  This
	      option may be used multiple times.

	      The Attribute ID can be in the range 1 to 255. If ´N´ is	speci‐
	      fied as ID, the settings for all Attributes are changed.

	      The  optional  BYTEORDER	consists of 1 to 8 characters from the
	      set ´012345rvwz´. The characters ´0´ to ´5´ select the byte 0 to
	      5	 from  the  48-bit raw value, ´r´ selects the reserved byte of
	      the attribute data block, ´v´ selects the normalized value,  ´w´
	      selects  the  worst  value  and  ´z´  inserts  a zero byte.  The
	      default BYTEORDER is ´543210´ for all 48-bit formats,  ´r543210´
	      for  the	54-bit formats, and ´543210wv´ for the 64-bit formats.
	      For  example,  ´-v  5,raw48:012345´  prints  the	raw  value  of
	      attribute 5 with big endian instead of little endian byte order‐
	      ing.

	      The NAME is a string of letters,	digits	and  underscore.   Its
	      length should not exceed 23 characters.  The ´-P showall´ option
	      reports an error if this is the case.

	      -v help - Prints (to STDOUT) a list of all  valid	 arguments  to
	      this option, then exits.

	      Valid arguments for FORMAT are:

	      raw8  -  Print the Raw value as six 8-bit unsigned base-10 inte‐
	      gers.  This may be useful for decoding the meaning  of  the  Raw
	      value.

	      raw16  -	Print  the  Raw value as three 16-bit unsigned base-10
	      integers.	 This may be useful for decoding the  meaning  of  the
	      Raw value.

	      raw48  -	Print the Raw value as a 48-bit unsigned base-10 inte‐
	      ger.  This is the default for most attributes.

	      hex48 - Print the Raw value as a 12  digit  hexadecimal  number.
	      This may be useful for decoding the meaning of the Raw value.

	      raw64  -	Print the Raw value as a 64-bit unsigned base-10 inte‐
	      ger.  This includes two bytes  from  the	normalized  and	 worst
	      attribute value.	This new raw format is used by some recent SSD
	      devices.

	      hex64 - Print the Raw value as a 16  digit  hexadecimal  number.
	      This  includes two bytes from the normalized and worst attribute
	      value.  This new raw format is used by some recent SSD devices.

	      min2hour - Raw Attribute is power-on time in minutes.   Its  raw
	      value  will  be displayed in the form "Xh+Ym".  Here X is hours,
	      and Y is minutes in the  range  0-59  inclusive.	 Y  is	always
	      printed with two digits, for example "06" or "31" or "00".

	      sec2hour	-  Raw Attribute is power-on time in seconds.  Its raw
	      value will be displayed in  the  form  "Xh+Ym+Zs".   Here	 X  is
	      hours,  Y	 is minutes in the range 0-59 inclusive, and Z is sec‐
	      onds in the range 0-59 inclusive.	 Y and Z  are  always  printed
	      with two digits, for example "06" or "31" or "00".

	      halfmin2hour - Raw Attribute is power-on time, measured in units
	      of 30 seconds.  This format is used by some Samsung disks.   Its
	      raw  value  will	be  displayed  in the form "Xh+Ym".  Here X is
	      hours, and Y is minutes in  the  range  0-59  inclusive.	 Y  is
	      always  printed  with  two  digits,  for example "06" or "31" or
	      "00".

	      msec24hour32 - Raw Attribute is power-on time measured in 32-bit
	      hours  and  24-bit milliseconds since last hour update.  It will
	      be displayed in the form "Xh+Ym+Z.Ms".  Here X is	 hours,	 Y  is
	      minutes, Z is seconds and M is milliseconds.

	      tempminmax  -  Raw Attribute is the disk temperature in Celsius.
	      Info about Min/Max temperature is printed if available.  This is
	      the  default for Attributes 190 and 194.	The recording interval
	      (lifetime, last power cycle, last soft  reset)  of  the  min/max
	      values is device specific.

	      temp10x  -  Raw  Attribute  is ten times the disk temperature in
	      Celsius.

	      raw16(raw16) - Print the raw attribute as a 16-bit value and two
	      optional	16-bit values if these words are nonzero.  This is the
	      default for Attributes 5 and 196.

	      raw16(avg16) - Raw attribute is spin-up time.  It is printed  as
	      a	 16-bit	 value	and  an optional "Average" 16-bit value if the
	      word is nonzero.	This is the default for Attribute 3.

	      raw24/raw24 - Raw Attribute  contains  two  24-bit  values.  The
	      first is the number of load cycles.  The second is the number of
	      unload cycles.  The difference between these two values  is  the
	      number  of  times	 that  the  drive was unexpectedly powered off
	      (also called an emergency unload).  As  a	 rule  of  thumb,  the
	      mechanical  stress created by one emergency unload is equivalent
	      to that created by one hundred normal unloads.

	      raw24/raw32 - Raw attribute is an error rate which consists of a
	      24-bit error count and a 32-bit total count.

	      The following old arguments to ´-v´ are also still valid:

	      9,minutes - same as: 9,min2hour,Power_On_Minutes.

	      9,seconds - same as: 9,sec2hour,Power_On_Seconds.

	      9,halfminutes - same as: 9,halfmin2hour,Power_On_Half_Minutes.

	      9,temp - same as: 9,tempminmax,Temperature_Celsius.

	      192,emergencyretractcyclect	   -	      same	   as:
	      192,raw48,Emerg_Retract_Cycle_Ct

	      193,loadunload - same as: 193,raw24/raw24.

	      194,10xCelsius - same as: 194,temp10x,Temperature_Celsius_x10.

	      194,unknown - same as: 194,raw48,Unknown_Attribute.

	      197,increasing - same as: 197,raw48,Total_Pending_Sectors.  Also
	      means  that  Attribute number 197 (Current Pending Sector Count)
	      is not reset  if	uncorrectable  sectors	are  reallocated  (see
	      smartd.conf(5) man page).

	      198,increasing  -	 same  as:  198,raw48,Total_Offl_Uncorrectabl.
	      Also means that Attribute number 198 (Offline Uncorrectable Sec‐
	      tor Count) is not reset if uncorrectable sectors are reallocated
	      (see smartd.conf(5) man page).

	      198,offlinescanuncsectorct    -	 same	 as:	198,raw48,Off‐
	      line_Scan_UNC_SectCt.

	      200,writeerrorcount - same as: 200,raw48,Write_Error_Count.

	      201,detectedtacount - same as: 201,raw48,Detected_TA_Count.

	      220,temp - same as: 220,raw48,Temperature_Celsius.

	      Note: a table of hard drive models, listing which Attribute cor‐
	      responds	  to	 temperature,	  can	  be	 found	   at:
	      http://www.guzu.net/linux/hddtemp.db

       -F TYPE, --firmwarebug=TYPE
	      [ATA  only]  Modifies the behavior of smartctl to compensate for
	      some known and understood device firmware or driver bug.	Except
	      ´swapid´,	 the  arguments	 to this option are exclusive, so that
	      only the final option given is used.  The valid values are:

	      none - Assume that the device firmware obeys the ATA  specifica‐
	      tions.   This  is the default, unless the device has presets for
	      ´-F´ in the device database (see note below).

	      samsung - In some Samsung disks (example: model SV4012H Firmware
	      Version:	RM100-08) some of the two- and four-byte quantities in
	      the SMART data structures are byte-swapped (relative to the  ATA
	      specification).  Enabling this option tells smartctl to evaluate
	      these quantities in byte-reversed order.	Some signs  that  your
	      disk  needs  this	 option are (1) no self-test log printed, even
	      though you have run self-tests; (2) very large  numbers  of  ATA
	      errors reported in the ATA error log; (3) strange and impossible
	      values for the ATA error log timestamps.

	      samsung2 - In some  Samsung  disks  the  number  of  ATA	errors
	      reported	is  byte swapped.  Enabling this option tells smartctl
	      to evaluate this quantity in byte-reversed order. An  indication
	      that  your  Samsung disk needs this option is that the self-test
	      log is printed correctly, but there are a very large  number  of
	      errors  in the SMART error log.  This is because the error count
	      is byte swapped.	Thus a disk with  five	errors	(0x0005)  will
	      appear to have 20480 errors (0x5000).

	      samsung3	-  Some	 Samsung disks (at least SP2514N with Firmware
	      VF100-37) report a self-test still in progress with 0% remaining
	      when  the test was already completed. Enabling this option modi‐
	      fies the output of the self-test execution status	 (see  options
	      ´-c´ or ´-a´ above) accordingly.

	      Note  that  an  explicit	´-F´  option  on the command line will
	      over-ride any preset  values  for	 ´-F´  (see  the  ´-P´	option
	      below).

	      swapid  -	 Fixes byte swapped ATA identify strings (device name,
	      serial number, firmware version) returned by some	 buggy	device
	      drivers.

       -P TYPE, --presets=TYPE
	      [ATA  only]  Specifies  whether  smartctl	 should use any preset
	      options that are available for this drive. By  default,  if  the
	      drive is recognized in the smartmontools database, then the pre‐
	      sets are used.

	      smartctl can automatically set  appropriate  options  for	 known
	      drives.	For  example,  the  Maxtor 4D080H4 uses Attribute 9 to
	      stores power-on time in minutes whereas  most  drives  use  that
	      Attribute to store the power-on time in hours.  The command-line
	      option ´-v 9,minutes´ ensures that smartctl correctly interprets
	      Attribute 9 in this case, but that option is preset for the Max‐
	      tor 4D080H4 and so need not be specified	by  the	 user  on  the
	      smartctl command line.

	      The  argument  show  will show any preset options for your drive
	      and the argument showall will  show  all	known  drives  in  the
	      smartmontools  database,	along  with  their preset options.  If
	      there are no presets for your drive and you think	 there	should
	      be  (for example, a -v or -F option is needed to get smartctl to
	      display correct values) then please  contact  the	 smartmontools
	      developers  so  that this information can be added to the smart‐
	      montools database.  Contact information is at the	 end  of  this
	      man page.

	      The valid arguments to this option are:

	      use  - if a drive is recognized, then use the stored presets for
	      it.  This is the default. Note that presets will	NOT  over-ride
	      additional  Attribute  interpretation  (´-v  N,something´)  com‐
	      mand-line options or explicit ´-F´ command-line options..

	      ignore - do not use presets.

	      show - show if the drive is recognized in the database,  and  if
	      so, its presets, then exit.

	      showall  -  list all recognized drives, and the presets that are
	      set for them, then exit.	This also checks  the  drive  database
	      regular expressions and settings for syntax errors.

	      The  ´-P	showall´  option takes up to two optional arguments to
	      match a specific drive type and firmware version. The command:
		smartctl -P showall
	      lists all entries, the command:
		smartctl -P showall ´MODEL´
	      lists all entries matching MODEL, and the command:
		smartctl -P showall ´MODEL´ ´FIRMWARE´
	      lists all entries for this MODEL and a  specific	FIRMWARE  ver‐
	      sion.

       -B [+]FILE, --drivedb=[+]FILE
	      [ATA  only] Read the drive database from FILE.  The new database
	      replaces the built in database by default.  If ´+´ is specified,
	      then the new entries prepend the built in entries.

	      Optional	entries are read from the file /etc/smart_drivedb.h if
	      this option is not specified.

	      If /usr/share/smartmontools/drivedb.h is present,	 the  contents
	      of this file is used instead of the built in table.

	      Run  /usr/sbin/update-smart-drivedb to update this file from the
	      smartmontools SVN repository.

	      The database files use the same C/C++ syntax  that  is  used  to
	      initialize the built in database array. C/C++ style comments are
	      allowed.	Example:

		/* Full entry: */
		{
		  "Model family",    // Info about model family/series.
		  "MODEL1.*REGEX",   // Regular expression to match model of device.
		  "VERSION.*REGEX",  // Regular expression to match firmware version(s).
		  "Some warning",    // Warning message.
		  "-v 9,minutes"     // String of preset -v and -F options.
		},
		/* Minimal entry: */
		{
		  "",		     // No model family/series info.
		  "MODEL2.*REGEX",   // Regular expression to match model of device.
		  "",		     // All firmware versions.
		  "",		     // No warning.
		  ""		     // No options preset.
		},
		/* USB ID entry: */
		{
		  "USB: Device; Bridge", // Info about USB device and bridge name.
		  "0x1234:0xabcd",   // Regular expression to match vendor:product ID.
		  "0x0101",	     // Regular expression to match bcdDevice.
		  "",		     // Not used.
		  "-d sat"	     // String with device type option.
		},
		/* ... */

       SMART RUN/ABORT OFFLINE TEST AND SELF-TEST OPTIONS:

       -t TEST, --test=TEST
	      Executes TEST immediately.  The ´-C´ option can be used in  con‐
	      junction with this option to run the short or long (and also for
	      ATA devices, selective or conveyance) self-tests in captive mode
	      (known  as  "foreground mode" for SCSI devices).	Note that only
	      one test type can be run at a time, so only one test type should
	      be  specified per command line.  Note also that if a computer is
	      shutdown or power cycled during  a  self-test,  no  harm	should
	      result.	The  self-test	will  either be aborted or will resume
	      automatically.

	      The valid arguments to this option are:

	      offline - [ATA] runs SMART Immediate Offline Test.  This immedi‐
	      ately  starts  the  test	described  above.  This command can be
	      given during normal system operation.  The effects of this  test
	      are  visible only in that it updates the SMART Attribute values,
	      and if errors are found they will appear in the SMART error log,
	      visible with the ´-l error´ option.

	      If  the  ´-c´  option  to smartctl shows that the device has the
	      "Suspend Offline collection upon new  command"  capability  then
	      you  can	track the progress of the Immediate Offline test using
	      the ´-c´ option to smartctl.  If the ´-c´ option show  that  the
	      device has the "Abort Offline collection upon new command" capa‐
	      bility then most commands will abort the Immediate Offline Test,
	      so  you  should  not  try to track the progress of the test with
	      ´-c´, as it will abort the test.

	      offline - [SCSI] runs the default self test  in  foreground.  No
	      entry is placed in the self test log.

	      short - [ATA] runs SMART Short Self Test (usually under ten min‐
	      utes).  This command can be given during normal system operation
	      (unless  run in captive mode - see the ´-C´ option below).  This
	      is a test in a different category than the  immediate  or	 auto‐
	      matic  offline tests.  The "Self" tests check the electrical and
	      mechanical performance as well as the read  performance  of  the
	      disk.   Their  results  are reported in the Self Test Error Log,
	      readable with the ´-l selftest´ option.  Note that on some disks
	      the  progress of the self-test can be monitored by watching this
	      log during the self-test; with other disks use the  ´-c´	option
	      to monitor progress.

	      short - [SCSI] runs the "Background short" self-test.

	      long  -  [ATA]  runs SMART Extended Self Test (tens of minutes).
	      This is a longer and more thorough version  of  the  Short  Self
	      Test  described above.  Note that this command can be given dur‐
	      ing normal system operation (unless run in captive  mode	-  see
	      the ´-C´ option below).

	      long - [SCSI] runs the "Background long" self-test.

	      conveyance  - [ATA only] runs a SMART Conveyance Self Test (min‐
	      utes).  This self-test routine is intended  to  identify	damage
	      incurred	during transporting of the device. This self-test rou‐
	      tine should take on the order of minutes to complete.  Note that
	      this command can be given during normal system operation (unless
	      run in captive mode - see the ´-C´ option below).

	      select,N-M, select,N+SIZE - [ATA only] runs  a  SMART  Selective
	      Self  Test,  to  test  a	range  of disk Logical Block Addresses
	      (LBAs), rather than the entire disk.  Each range of LBAs that is
	      checked  is  called  a "span" and is specified by a starting LBA
	      (N) and an ending LBA (M) with N less than or equal  to  M.  The
	      range  can  also	be specified as N+SIZE. A span at the end of a
	      disk can be specified by N-max.

	      For example the commands:
		smartctl -t select,10-20 /dev/hda
		smartctl -t select,10+11 /dev/hda
	      both runs a self test on one span	 consisting  of	 LBAs  ten  to
	      twenty (inclusive). The command:
		smartctl -t select,100000000-max /dev/hda
	      run  a  self  test from LBA 100000000 up to the end of the disk.
	      The ´-t´ option can be given up to five times,  to  test	up  to
	      five spans.  For example the command:
		smartctl -t select,0-100 -t select,1000-2000 /dev/hda
	      runs  a  self test on two spans.	The first span consists of 101
	      LBAs and the second span consists of 1001 LBAs.  Note  that  the
	      spans can overlap partially or completely, for example:
		smartctl -t select,0-10 -t select,5-15 -t select,10-20 /dev/hda
	      The  results  of	the  selective self-test can be obtained (both
	      during and after the test) by printing the SMART self-test  log,
	      using the ´-l selftest´ option to smartctl.

	      Selective	 self tests are particularly useful as disk capacities
	      increase: an extended self test (smartctl -t long) can take sev‐
	      eral  hours.  Selective self-tests are helpful if (based on SYS‐
	      LOG error messages, previous failed self-tests, or  SMART	 error
	      log  entries)  you  suspect  that a disk is having problems at a
	      particular range of Logical Block Addresses (LBAs).

	      Selective self-tests can be run during normal  system  operation
	      (unless done in captive mode - see the ´-C´ option below).

	      The  following  variants	of the selective self-test command use
	      spans based on the ranges from past tests already stored on  the
	      disk:

	      select,redo[+SIZE]  -  [ATA  only] redo the last SMART Selective
	      Self Test using the same LBA range. The starting LBA is  identi‐
	      cal  to  the LBA used by last test, same for ending LBA unless a
	      new span size is specified by optional +SIZE argument.

	      For example the commands:
		smartctl -t select,10-20 /dev/hda
		smartctl -t select,redo /dev/hda
		smartctl -t select,redo+20 /dev/hda
	      have the same effect as:
		smartctl -t select,10-20 /dev/hda
		smartctl -t select,10-20 /dev/hda
		smartctl -t select,10-29 /dev/hda

	      select,next[+SIZE] - [ATA only] runs a SMART Selective Self Test
	      on  the  LBA range which follows the range of the last test. The
	      starting LBA is set to (ending LBA +1) of the last test.	A  new
	      span size may be specified by the optional +SIZE argument.

	      For example the commands:
		smartctl -t select,0-999 /dev/hda
		smartctl -t select,next /dev/hda
		smartctl -t select,next+2000 /dev/hda
	      have the same effect as:
		smartctl -t select,0-999 /dev/hda
		smartctl -t select,1000-1999 /dev/hda
		smartctl -t select,2000-3999 /dev/hda

	      If  the  last  test  ended  at the last LBA of the disk, the new
	      range starts at LBA 0. The span size of the last span of a  disk
	      is  adjusted  such  that	the total number of spans to check the
	      full  disk  will	not  be	 changed  by  future   uses   of   ´-t
	      select,next´.

	      select,cont[+SIZE] - [ATA only] performs a ´redo´ (above) if the
	      self test status reports that the last test was aborted  by  the
	      host. Otherwise it run the ´next´ (above) test.

	      afterselect,on - [ATA only] perform an offline read scan after a
	      Selective Self-test has completed.  This	option	must  be  used
	      together	with  one  or more of the select,N-M options above. If
	      the LBAs that have been specified	 in  the  Selective  self-test
	      pass the test with no errors found, then read scan the remainder
	      of the disk.  If the device is powered-cycled  while  this  read
	      scan is in progress, the read scan will be automatically resumed
	      after a time specified by the pending timer  (see	 below).   The
	      value of this option is preserved between selective self-tests.

	      afterselect,off  -  [ATA only] do not read scan the remainder of
	      the disk after a Selective self-test has completed.  This option
	      must  be use together with one or more of the select,N-M options
	      above.  The value of this option is preserved between  selective
	      self-tests.

	      pending,N	 -  [ATA only] set the pending offline read scan timer
	      to N minutes.  Here N is an integer in the range from 0 to 65535
	      inclusive.   If  the  device  is	powered off during a read scan
	      after a Selective self-test, then resume the test	 automatically
	      N minutes after power-up.	 This option must be use together with
	      one or more of the select,N-M options above. The value  of  this
	      option is preserved between selective self-tests.

	      vendor,N	- [ATA only] issues the ATA command SMART EXECUTE OFF-
	      LINE IMMEDIATE with subcommand N in LBA LOW register.  The  sub‐
	      command  is  specified as a hex value in the range 0x00 to 0xff.
	      Subcommands 0x40-0x7e and 0x90-0xff are reserved for vendor spe‐
	      cific  use,  see	table 61 of T13/1699-D Revision 6a (ATA8-ACS).
	      Note that the subcommands 0x00-0x04,0x7f,0x81-0x84 are supported
	      by  other	 smartctl  options (e.g. 0x01: ´-t short´, 0x7f: ´-X´,
	      0x82: ´-C -t long´).

	      WARNING: Only run subcommands documented by the  vendor  of  the
	      device.

	      Example for Intel (X18-M/X25-M G2 and 320 Series) SSDs only: The
	      subcommand 0x40 (´-t vendor,0x40´)  clears  the  timed  workload
	      related  SMART  attributes  (226,	 227, 228).  Note that the raw
	      values of these attributes are held at 65535 (0xffff) until  the
	      workload timer reaches 60 minutes.

	      scttempint,N[,p]	 -  is	no  longer  supported,	use  ´-l  sct‐
	      tempint,N[,p]´ instead, see above.

       -C, --captive
	      [ATA] Runs self-tests in captive mode.  This has no effect  with
	      ´-t offline´ or if the ´-t´ option is not used.

	      WARNING:	Tests  run  in captive mode may busy out the drive for
	      the length of the test.  Only run captive tests on drives	 with‐
	      out any mounted partitions!

	      [SCSI] Runs the self-test in "Foreground" mode.

       -X, --abort
	      Aborts  non-captive  SMART  Self	Tests.	Note that this command
	      will abort the Offline Immediate Test routine only if your  disk
	      has the "Abort Offline collection upon new command" capability.

ATA, SCSI command sets and SAT
       In  the past there has been a clear distinction between storage devices
       that used the ATA and SCSI command sets.	 This  distinction  was	 often
       reflected  in their device naming and hardware. Now various SCSI trans‐
       ports (e.g. SAS, FC and iSCSI) can  interconnect	 to  both  SCSI	 disks
       (e.g.  FC  and  SAS) and ATA disks (especially SATA). USB and IEEE 1394
       storage devices use the SCSI command set externally but	almost	always
       contain	ATA  or	 SATA disks (or flash). The storage subsystems in some
       operating systems have started to remove the  distinction  between  ATA
       and SCSI in their device naming policies.

       99%  of	operations  that  an  OS  performs  on a disk involve the SCSI
       INQUIRY, READ CAPACITY, READ and WRITE commands, or their  ATA  equiva‐
       lents. Since the SCSI commands are slightly more general than their ATA
       equivalents, many OSes are generating SCSI commands  (mainly  READ  and
       WRITE)  and  letting  a lower level translate them to their ATA equiva‐
       lents as the need arises. An important note here is that "lower	level"
       may be in external equipment and hence outside the control of an OS.

       SCSI to ATA Translation (SAT) is a standard (ANSI INCITS 431-2007) that
       specifies how this translation is done. For the other 1% of  operations
       that  an	 OS  performs on a disk, SAT provides two options. First is an
       optional ATA PASS-THROUGH SCSI command (there are  two  variants).  The
       second  is  a  translation  from the closest SCSI command. Most current
       interest is in the "pass-through" option.

       The relevance to smartmontools (and hence smartctl) is that its	inter‐
       actions	with disks fall solidly into the "1%" category. So even if the
       OS can happily treat (and name) a disk as "SCSI",  smartmontools	 needs
       to  detect the native command set and act accordingly.  As more storage
       manufacturers (including external SATA drives) comply with SAT,	smart‐
       montools is able to automatically distinguish the native command set of
       the device. In some cases the '-d sat' option is needed on the  command
       line.

       There are also virtual disks which typically have no useful information
       to convey to smartmontools, but could conceivably  in  the  future.  An
       example	of  a virtual disk is the OS's view of a RAID 1 box. There are
       most likely two SATA disks inside a RAID 1 box. Addressing  those  SATA
       disks  from  a  distant	OS  is	a challenge for smartmontools. Another
       approach is running a tool like smartmontools inside  the  RAID	1  box
       (e.g.   a Network Attached Storage (NAS) box) and fetching the logs via
       a browser.

EXAMPLES
       smartctl -a /dev/hda
       Print a large amount of SMART information for drive /dev/hda  which  is
       typically an ATA (IDE) or SATA disk in Linux.

       smartctl -a /dev/sdb
       Print a large amount of SMART information for drive /dev/sdb . This may
       be a SCSI disk or an ATA (SATA) disk.

       smartctl -s off /dev/hdd
       Disable SMART monitoring and data log collection on drive /dev/hdd .

       smartctl --smart=on --offlineauto=on --saveauto=on /dev/hda
       Enable SMART on drive /dev/hda, enable automatic offline testing	 every
       four  hours, and enable autosaving of SMART Attributes.	This is a good
       start-up line for your system´s init files.  You can issue this command
       on a running system.

       smartctl -t long /dev/hdc
       Begin an extended self-test of drive /dev/hdc.  You can issue this com‐
       mand on a running system.  The results can be seen in the self-test log
       visible with the ´-l selftest´ option after it has completed.

       smartctl -s on -t offline /dev/hda
       Enable  SMART on the disk, and begin an immediate offline test of drive
       /dev/hda.  You can issue this command on a running system.  The results
       are  only  used	to  update the SMART Attributes, visible with the ´-A´
       option.	If any device errors occur, they are logged to the SMART error
       log, which can be seen with the ´-l error´ option.

       smartctl -A -v 9,minutes /dev/hda
       Shows  the  vendor  Attributes,	when the disk stores its power-on time
       internally in minutes rather than hours.

       smartctl -q errorsonly -H -l selftest /dev/hda
       Produces output only if the device returns failing SMART status, or  if
       some of the logged self-tests ended with errors.

       smartctl -q silent -a /dev/hda
       Examine all SMART data for device /dev/hda, but produce no printed out‐
       put.  You must use the exit status (the $?  shell variable) to learn if
       any  Attributes	are  out  of bound, if the SMART status is failing, if
       there are errors recorded in the self-test log, or if there are	errors
       recorded in the disk error log.

       smartctl -a -d 3ware,0 /dev/sda
       Examine all SMART data for the first ATA disk connected to a 3ware RAID
       controller card.

       smartctl -a -d 3ware,0 /dev/twe0
       Examine all SMART data for the first ATA disk connected to a 3ware RAID
       6000/7000/8000 controller card.

       smartctl -a -d 3ware,0 /dev/twa0
       Examine all SMART data for the first ATA disk connected to a 3ware RAID
       9000 controller card.

       smartctl -a -d 3ware,0 /dev/twl0
       Examine all SMART data for the first SATA (not SAS) disk connected to a
       3ware RAID 9750 controller card.

       smartctl -t short -d 3ware,3 /dev/sdb
       Start  a	 short self-test on the fourth ATA disk connected to the 3ware
       RAID controller card which is the second SCSI device /dev/sdb.

       smartctl -t long -d areca,4 /dev/sg2
       Start a long self-test on the fourth SATA disk connected	 to  an	 Areca
       RAID controller addressed by /dev/sg2.

       smartctl -a -d hpt,1/3 /dev/sda (under Linux)
       smartctl -a -d hpt,1/3 /dev/hptrr (under FreeBSD)
       Examine	all  SMART  data for the (S)ATA disk directly connected to the
       third channel of the first HighPoint RocketRAID controller card.

       smartctl -t short -d hpt,1/1/2 /dev/sda (under Linux)
       smartctl -t short -d hpt,1/1/2 /dev/hptrr (under FreeBSD)
       Start a short self-test on the (S)ATA disk connected to	second	pmport
       on the first channel of the first HighPoint RocketRAID controller card.

       smartctl -t select,10-100 -t select,30-300 -t afterselect,on -t pending,45 /dev/hda
       Run  a  selective self-test on LBAs 10 to 100 and 30 to 300.  After the
       these LBAs have been tested, read-scan the remainder of the  disk.   If
       the  disk is power-cycled during the read-scan, resume the scan 45 min‐
       utes after power to the device is restored.

       smartctl -a -d cciss,0 /dev/cciss/c0d0
       Examine all SMART data for the first SCSI disk  connected  to  a	 cciss
       RAID controller card.

RETURN VALUES
       The return values of smartctl are defined by a bitmask.	If all is well
       with the disk, the return value (exit status) of	 smartctl  is  0  (all
       bits  turned  off).  If a problem occurs, or an error, potential error,
       or fault is detected, then a non-zero  status  is  returned.   In  this
       case,  the  eight different bits in the return value have the following
       meanings for ATA disks; some of these values may also be	 returned  for
       SCSI disks.

       Bit 0: Command line did not parse.

       Bit 1: Device  open  failed,  device  did not return an IDENTIFY DEVICE
	      structure, or device is in a low-power  mode  (see  ´-n´	option
	      above).

       Bit 2: Some  SMART  command to the disk failed, or there was a checksum
	      error in a SMART data structure (see ´-b´ option above).

       Bit 3: SMART status check returned "DISK FAILING".

       Bit 4: We found prefail Attributes <= threshold.

       Bit 5: SMART status check returned "DISK OK" but	 we  found  that  some
	      (usage  or  prefail)  Attributes	have been <= threshold at some
	      time in the past.

       Bit 6: The device error log contains records of errors.

       Bit 7: The device self-test log contains records of errors.  [ATA only]
	      Failed  self-tests  outdated  by	a  newer  successful  extended
	      self-test are ignored.

       To test within the shell for whether or	not  the  different  bits  are
       turned  on or off, you can use the following type of construction (this
       is bash syntax):
       smartstat=$(($? & 8))
       This looks at only at bit 3 of the exit status $?  (since 8=2^3).   The
       shell  variable	$smartstat  will  be  nonzero  if  SMART  status check
       returned "disk failing" and zero otherwise.

       This bash script prints all status bits:
       status=$?
       for ((i=0; i<8; i++)); do
	 echo "Bit $i: $((status & 2**i && 1))"
       done

NOTES
       The TapeAlert log page flags are cleared for  the  initiator  when  the
       page  is	 read.	This  means that each alert condition is reported only
       once by smartctl for each initiator for each activation of  the	condi‐
       tion.

AUTHOR
       Bruce Allen smartmontools-support@lists.sourceforge.net
       University of Wisconsin - Milwaukee Physics Department

CONTRIBUTORS
       The following have made large contributions to smartmontools:
       Casper Dik (Solaris SCSI interface)
       Christian Franke (Windows interface, C++ redesign, USB support, ...)
       Douglas Gilbert (SCSI subsystem)
       Guido Guenther (Autoconf/Automake packaging)
       Geoffrey Keating (Darwin ATA interface)
       Eduard Martinescu (FreeBSD interface)
       Frédéric L. W. Meunier (Web site and Mailing list)
       Gabriele Pohl (Web site and Wiki, conversion from CVS to SVN)
       Keiji Sawada (Solaris ATA interface)
       Manfred Schwarb (Drive database)
       Sergey Svishchev (NetBSD interface)
       David Snyder and Sergey Svishchev (OpenBSD interface)
       Phil Williams (User interface and drive database)
       Yuri Dario (OS/2, eComStation interface)
       Shengfeng Zhou (Linux/FreeBSD HighPoint RocketRAID interface)
       Many other individuals have made smaller contributions and corrections.

CREDITS
       This  code  was derived from the smartsuite package, written by Michael
       Cornwell, and from the previous UCSC smartsuite	package.   It  extends
       these  to  cover	 ATA-5 disks.  This code was originally developed as a
       Senior Thesis by Michael Cornwell at the Concurrent Systems  Laboratory
       (now  part  of the Storage Systems Research Center), Jack Baskin School
       of    Engineering,    University	   of	 California,	Santa	 Cruz.
       http://ssrc.soe.ucsc.edu/ .

HOME PAGE FOR SMARTMONTOOLS:
       Please  see  the following web site for updates, further documentation,
       bug reports and patches: http://smartmontools.sourceforge.net/

SEE ALSO:
       smartd(8), badblocks(8), ide-smart(8).

REFERENCES FOR SMART
       An introductory article about smartmontools is  Monitoring  Hard	 Disks
       with  SMART,  by Bruce Allen, Linux Journal, January 2004, pages 74-77.
       This is http://www.linuxjournal.com/article/6983 online.

       If you would like to understand better how SMART	 works,	 and  what  it
       does,  a good place to start is with Sections 4.8 and 6.54 of the first
       volume of the ´AT Attachment  with  Packet  Interface-7´	 (ATA/ATAPI-7)
       specification  Revision	4b.   This  documents  the SMART functionality
       which the smartmontools utilities provide access to.

       The functioning of SMART was originally defined by the SFF-8035i	 revi‐
       sion 2 and the SFF-8055i revision 1.4 specifications.  These are publi‐
       cations of the Small Form Factors (SFF) Committee.

       Links to these and other documents may be found on the  Links  page  of
       the  smartmontools  Wiki	 at http://sourceforge.net/apps/trac/smartmon‐
       tools/wiki/Links .

SVN ID OF THIS PAGE:
       $Id: smartctl.8.in 3452 2011-10-15 15:22:09Z chrfranke $

smartmontools-5.42		  2011-10-20			   SMARTCTL(8)
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