Provided by: smartmontools_7.0-0ubuntu1_amd64 bug

NAME

       smartctl - Control and Monitor Utility for SMART Disks

SYNOPSIS

       smartctl [options] device

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  Technology  (SMART)  system
       built  into most ATA/SATA and SCSI/SAS hard drives and solid-state 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.  smartctl also supports some features not
       related to SMART.  This version of smartctl is compatible  with  ACS-3,  ACS-2,  ATA8-ACS,
       ATA/ATAPI-7 and earlier standards (see REFERENCES below).

       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/sd[a-z]" for ATA/SATA and SCSI/SAS devices.  For SCSI Tape
                Drives and Changers with  TapeAlert  support  use  the  devices  "/dev/nst*"  and
                "/dev/sg*".   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)!   For
                HP  Smart  Array  RAID  controllers, there are three currently supported drivers:
                cciss, hpsa, and hpahcisr.  For disks accessed via the cciss  driver  the  device
                nodes are of the form "/dev/cciss/c[0-9]d0".  For disks accessed via the hpahcisr
                and hpsa drivers, the device nodes you need are "/dev/sg[0-9]*".  ("lsscsi -g" is
                helpful  in  determining  which  scsi  generic  device  node corresponds to which
                device.)  Use the nodes corresponding to the  RAID  controllers,  not  the  nodes
                corresponding  to  logical  drives.   See  the -d option below, as well.  Use the
                forms "/dev/nvme[0-9]" (broadcast namespace) or "/dev/nvme[0-9]n[1-9]"  (specific
                namespace 1-9) for NVMe devices.

       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.

       smartctl guesses the device type if possible.  If necessary, the '-d' option can  be  used
       to override 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 (hexadecimal).  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.

       -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  currently 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 database (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.

              [NVMe]  For  NVMe  devices the information is obtained from the Identify Controller
              and the Identify Namespace data structure.

       --identify[=[w][nvb]]
              [ATA only] Prints an annotated table of the IDENTIFY DEVICE data.  By default, only
              valid  words  (words not equal to 0x0000 or 0xffff) and nonzero bits and bit fields
              are printed.  This can be changed by the optional argument which consists of one or
              two  characters from the set 'wnvb'.  The character 'w' enables printing of all 256
              words.  The character 'n' suppresses printing of bits, 'v' enables printing of  all
              bits   from   valid   words,  'b'  enables  printing  of  all  bits.   For  example
              '--identify=n'  (valid  words,  no  bits)  produces   the   shortest   output   and
              '--identify=wb' (all words, all bits) produces the longest output.

       -a, --all
              Prints  all  SMART  information  about the disk, or TapeAlert information 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'.
              For NVMe, this is equivalent to
              '-H -i -c -A -l error'.
              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 -g all -g wcreorder -c -A -f brief -l xerror,error -l xselftest,selftest  -l
              selective -l directory -l scttemp -l scterc -l devstat -l defects -l sataphy'.
              and for SCSI, this is equivalent to
              '-H -i -g all -A -l error -l selftest -l background -l sasphy'.
              For NVMe, this is equivalent to
              '-H -i -c -A -l error'.

       --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  printing  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 example:
              smartctl --scan-open -- -a -W 4,45,50 -m admin@work > smartd.conf

              Multiple  '-d  TYPE'  options  may be specified with '--scan[-open]' to combine the
              scan results of more than one TYPE.

       -g NAME, --get=NAME
              Get non-SMART device settings.  See '-s, --set' below for further info.

       RUN-TIME BEHAVIOR OPTIONS:

       -j, --json[=cgiosuv]
              [NEW EXPERIMENTAL SMARTCTL FEATURE] Enables JSON output mode.

              The output could be modified or enhanced by the optional argument which consists of
              one or more characters from the set 'cgiosuv':
              'c':  Outputs compact format without extra spaces and newlines.  By default, output
              is pretty-printed.
              'g': Outputs JSON structure as single assignments to allow the usage of grep.  Each
              assignment  reflects  the  absolute path of a value.  The syntax is compatible with
              gron:
              'json.KEY1[INDEX2].KEY3 = VALUE;'.
              'o': Includes the full original plaintext  output  of  smartctl  as  a  JSON  array
              'smartctl.output[]'.
              's':  Outputs  JSON object elements sorted by key.  By default, object elements are
              ordered as generated internally.
              'v': Enables verbose output of possible  unsafe  integers.   If  specified,  values
              which  may  exceed  JSON  safe integer (53-bit) range are always output as a number
              (with some 'KEY') and a string ('KEY_s'), regardless of the actual  value.   Values
              which  may  exceed  64-bit  range  are  also  output  as a little endian byte array
              ('KEY_le').  By default, the additional elements  are  only  output  if  the  value
              actually exceeds the range.

              The following two arguments are primarily indented for development:
              'i':  Includes lines from the plaintext output which print info already implemented
              for JSON output.  The lines appear as objects with key 'smartctl_NNNN_i'.
              'u': Includes lines from the plaintext output which print info still  unimplemented
              for JSON output.  The lines appear as objects with key 'smartctl_NNNN_u'.

       -q TYPE, --quietmode=TYPE
              Specifies  that  smartctl should run in one of the 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 EXIT STATUS 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 exits without performing any further commands.

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

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

              nvme[,NSID]  -  the device type is NVM Express (NVMe).  The optional parameter NSID
              specifies the namespace id (in hex) passed to the driver.  Use 0xffffffff  for  the
              broadcast  namespace id.  The default for NSID is the namespace id addressed by the
              device name.

              sat[,auto][,N] - the device type is SCSI to ATA Translation (SAT).  This is for ATA
              disks  that  have  a  SCSI to ATA Translation 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'.

              If '-d sat,auto' is specified, device type SAT (for ATA/SATA disks) is only used if
              the  SCSI  INQUIRY data reports a SATL (VENDOR: "ATA     ").  Otherwise device type
              SCSI (for SCSI/SAS disks) is used.

              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
              usbcypress,0xN',  where  N  is  the scsi operation code, you're running the risk of
              damage to the device or filesystems on it.

              usbjmicron[,p][,x][,PORT] - 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 separate
              /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.

              The Prolific PL2507/3507 USB bridges with older  firmware  support  a  pass-through
              command  similar  to  JMicron  and  work  with  '-d  usbjmicron,0'.  Newer Prolific
              firmware requires a modified command which can be selected  by  '-d  usbjmicron,p'.
              Note that this does not yet support the SMART status command.

              usbprolific  -  this  device  type  is  for  SATA  disks that are behind a Prolific
              PL2571/2771/2773/2775 USB to SATA bridge.

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

              sntjmicron[,NSID]  -  [NEW  EXPERIMENTAL  SMARTCTL FEATURE] this device type is for
              NVMe disks that are behind a JMicron USB to NVMe bridge.   The  optional  parameter
              NSID  specifies  the  namespace  id  (in  hex)  passed  to the driver.  The default
              namespace id is the broadcast namespace id (0xffffffff).

              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-negative 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
              smartctl -a -d megaraid,0 /dev/bus/0
              This interface will also work for Dell PERC controllers.  It  is  possible  to  set
              RAID device name as /dev/bus/N, where N is a SCSI bus number.

              The following entry in /proc/devices must exist:
              For PERC2/3/4 controllers: megadevN
              For PERC5/6 controllers: megaraid_sas_ioctlN

              aacraid,H,L,ID  -  [Linux,  Windows  and Cygwin only] the device consists of one or
              more SCSI/SAS or SATA disks connected to an AacRaid controller.   The  non-negative
              integers  H,L,ID  (Host  number,  Lun,  ID)  denote which disk on the controller is
              monitored.  Use syntax such as:
              smartctl -a -d aacraid,0,0,2 /dev/sda
              smartctl -a -d aacraid,1,0,4 /dev/sdb

              Option '-d sat,auto+...' is implicitly enabled  to  detect  SATA  disks.   Use  '-d
              scsi+aacraid,H,L,ID' to disable it.

              On  Linux,  the following entry in /proc/devices must exist: aac.  Character device
              nodes /dev/aacH (H=Host number) are created if required.

              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  [Linux only]
              smartctl -a -d 3ware,0 /dev/twe0
              smartctl -a -d 3ware,1 /dev/twa0
              smartctl -a -d 3ware,1 /dev/twl0 [Linux only]
              smartctl -a -d 3ware,1 /dev/tws0 [FreeBSD only]
              The   first   two  forms,  which  refer  to  devices  /dev/sda-z  (deprecated)  and
              /dev/twe0-15, may be used with 3ware series 6000, 7000, and 8000 series controllers
              that  use  the  3x-xxxx  driver.  The devices /dev/twa0-15, must be used with 3ware
              9000 series controllers, which use the 3w-9xxx driver.   The  devices  /dev/twl0-15
              [Linux]  or  /dev/tws0-15  [FreeBSD]  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/tw[ls]?,  /dev/twa?   and
              /dev/twe?  do  not  exist,  or  exist  with  the  incorrect major or minor numbers,
              smartctl will recreate them on the fly.

              areca,N - [FreeBSD, Linux, Windows and Cygwin 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.  On Linux 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 correct device on Linux, 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.

              areca,N/E - [FreeBSD, Linux, Windows and Cygwin only] the device consists of one or
              more SATA or SAS disks connected to an Areca SAS RAID controller.   The  integer  N
              (range  1  to  128)  denotes  the  channel  (slot) and E (range 1 to 8) denotes the
              enclosure.  Important: This requires Areca SAS controller firmware version 1.51  or
              later.

              cciss,N  -  [FreeBSD and Linux only] the device consists of one or more SCSI/SAS or
              SATA 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.

              Option '-d sat,auto+...' is implicitly enabled  to  detect  SATA  disks.   Use  '-d
              scsi+cciss,N' to disable it.

              To look at disks behind HP Smart Array controllers, use syntax such as:
              smartctl -a -d cciss,0 /dev/cciss/c0d0    (cciss driver under Linux)
              smartctl -a -d cciss,0 /dev/sg2    (hpsa or hpahcisr drivers under Linux)

              hpt,L/M/N  -  [FreeBSD and Linux only] the device consists of one or more ATA disks
              connected to a HighPoint RocketRAID controller.  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 inclusive, M are  from  1
              to  128 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 controllers under Linux and under FreeBSD, it
              is the character device which the driver registered (eg, /dev/hptrr, /dev/hptmv6).

              intelliprop,N[+TYPE] - [NEW EXPERIMENTAL SMARTCTL FEATURE] the device  consists  of
              multiple  ATA  disks  connected to an Intelliprop controller.  The integer N is the
              port number from 0 to 3 of  the  ATA  drive  to  be  targeted.   The  TYPE  can  be
              ata(default),  sat,  or a USB controller listed above.  Note: if a type of ATA does
              not work, try a type of sat.  Use syntax such as:
              smartctl -a -d intelliprop,1 /dev/sda    (under Linux)
              smartctl -a -d intelliprop,1+sat /dev/sda    (under Linux)
              WARNING: The disks are selected by write commands to the ATA Device Vendor Specific
              Log  at  address  0xc0.   Using this option with other devices may have undesirable
              side effects.

       -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  Specification  if  the
              device  implements the SMART command set" and "optional" means "not required by the
              ATA 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 implemented", 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  supported", followed shortly by "Feature X enable
              failed".  In a few such cases, contrary to the final message, Feature X is enabled.

              verypermissive - equivalent to giving a large number of  '-T  permissive'  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  checksum  error  is
              detected  in the: (1) Device Identity Structure, (2) SMART Self-Test Log Structure,
              (3) SMART Attribute Value Structure, (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 conforming 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 corresponding status.  Invoking it a  second
              time adds a hex listing of the first 64 bytes of data send to, or received from the
              device.

              nvmeioctl - report only ioctl() transactions with NVMe devices.

              Any argument may include a positive integer to specify the  level  of  detail  that
              should  be  reported.   The argument should be followed 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 argument.  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[,STATUS], --nocheck=POWERMODE[,STATUS]
              [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.

              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.

              By default, exit status 2 is returned if the device is in one of the specified low-
              power modes.  This status is also returned if the  device  open  or  identification
              failed (see EXIT STATUS below).

              [NEW  EXPERIMENTAL  SMARTCTL  FEATURE]  The  optional  STATUS  parameter  allows to
              override this default.  STATUS is an integer in the range from 0 to 255  inclusive.
              For example use '-n standby,0' to return success if a device is in SLEEP or STANDBY
              mode.  Use '-n standby,3' to return a unique exit status in this case.

              The valid arguments to this option are:

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

              sleep[,STATUS] - check the device unless it is in SLEEP mode.

              standby[,STATUS] - 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[,STATUS] - 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.

              [ATA]  Note  that  the  ATA  commands SMART ENABLE/DISABLE OPERATIONS were declared
              obsolete in ATA ACS-4 Revision 10 (Nov 2015).

              [SCSI tape drive or changer] 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 Specifications.  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.   You  can  tell  if  automatic
              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 performance 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 otherwise 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 immediately.

              The choice (made by the SFF-8035i  and  ATA  specification  authors)  of  the  word
              testing  for  these  first  two  categories  is  unfortunate,  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 second 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 (immediately) 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 selftest' 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-specific 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.

              Note that the ATA commands SMART ENABLE/DISABLE AUTOSAVE were declared obsolete  in
              ATA ACS-4 Revision 10 (Nov 2015).

              [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 prevents 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 applications
              you might consider using off to set the GLTSD bit.

       -g NAME, --get=NAME, -s NAME[,VALUE], --set=NAME[,VALUE]
              Gets/sets non-SMART device settings.  Note that the '--set' option shares its short
              option '-s' with '--smart'.  Valid arguments are:

              all - Gets all values.  This is equivalent to
              '-g aam -g apm -g lookahead -g security -g wcache -g rcache -g dsn'

              aam[,N|off]  - [ATA only] Gets/sets the Automatic Acoustic Management (AAM) feature
              (if supported).  A value of 128 sets the most quiet  (slowest)  mode  and  254  the
              fastest  (loudest)  mode,  'off'  disables  AAM.   Devices may support intermediate
              levels.  Values below 128 are defined as vendor specific (0) or retired (1 to 127).
              Note  that  the  AAM  feature  was  declared obsolete in ATA ACS-2 Revision 4a (Dec
              2010).

              apm[,N|off] - [ATA only] Gets/sets the Advanced Power Management (APM)  feature  on
              device  (if  supported).  If a value between 1 and 254 is provided, it will attempt
              to enable APM and set the specified value, 'off' disables  APM.   Note  the  actual
              behavior  depends  on the drive, for example some drives disable APM if their value
              is set above 128.  Values below 128 are supposed to allow  drive  spindown,  values
              128  and  above  adjust  only  head-parking frequency, although the actual behavior
              defined is also vendor-specific.

              lookahead[,on|off]  -  [ATA  only]  Gets/sets  the  read  look-ahead  feature   (if
              supported).  Read look-ahead is usually enabled by default.

              security  -  [ATA only] Gets the status of ATA Security feature (if supported).  If
              ATA Security is enabled an ATA user password is set.  The drive will be  locked  on
              next reset then.

              security-freeze  -  [ATA  only]  Sets  ATA  Security  feature to frozen mode.  This
              prevents that the drive accepts any security commands until next reset.  Note  that
              the frozen mode may already be set by BIOS or OS.

              standby,[N|off] - [ATA only] Sets the standby (spindown) timer and places the drive
              in the IDLE mode.  A value of 0 or 'off' disables the standby timer.  Values from 1
              to  240  specify  timeouts  from  5  seconds  to 20 minutes in 5 second increments.
              Values from 241 to 251 specify timeouts from 30 minutes to 330 minutes in 30 minute
              increments.  Value 252 specifies 21 minutes.  Value 253 specifies a vendor specific
              time between 8 and 12 hours.  Value 255 specifies 21 minutes and 15 seconds.   Some
              drives may use a vendor specific interpretation for the values.  Note that there is
              no get option because ATA standards do not specify a method  to  read  the  standby
              timer.
              [NEW  EXPERIMENTAL  SMARTCTL  FEATURE]  If  '-s standby,now' is also specified, the
              drive is immediately placed in the STANDBY mode without temporarily placing  it  in
              the IDLE mode.  Note that ATA standards do not specify a command to set the standby
              timer without affecting the power mode.

              standby,now - [ATA only] Places the drive in the STANDBY mode.  This usually  spins
              down  the  drive.   The  setting  of  the  standby timer is not affected unless '-s
              standby,[N|off]' is also specified.

              wcache[,on|off] - [ATA] Gets/sets the volatile write cache feature (if  supported).
              The write cache is usually enabled by default.

              wcache[,on|off]  -  [SCSI]  Gets/sets  the  'Write  Cache  Enable'  (WCE)  bit  (if
              supported).  The write cache is usually enabled by default.

              wcache-sct[,ata|on|off[,p]]  -  [ATA  only]  [NEW  EXPERIMENTAL  SMARTCTL  FEATURE]
              Gets/sets  the write cache feature through SCT Feature Control (if supported).  The
              state of write cache in SCT Feature Control could be "Controlled  by  ATA",  "Force
              Enabled",  or  "Force Disabled".  SCT Feature control overwrites the setting by ATA
              Set Features command (wcache[,on|off] option).  If SCT Feature Control  sets  write
              cache  as  "Force  Enabled"  or "Force Disabled", the setting of wcache[,on|off] is
              ignored by the drive.  SCT Feature Control usually sets write cache as  "Controlled
              by  ATA"  by  default.  If ',p' is specified, the setting is preserved across power
              cycles.

              wcreorder[,on|off[,p]] - [ATA only] Gets/sets Write Cache  Reordering.   If  it  is
              disabled  (off),  disk  write scheduling is executed on a first-in-first-out (FIFO)
              basis.  If Write Cache Reordering is enabled (on), then disk write  scheduling  may
              be  reordered  by  the  drive.  If write cache is disabled, the current Write Cache
              Reordering state is remembered but has no effect on non-cached  writes,  which  are
              always  written  in the order received.  The state of Write Cache Reordering has no
              effect on either NCQ or LCQ queued commands.  [NEW EXPERIMENTAL  SMARTCTL  FEATURE]
              If ',p' is specified, the setting is preserved across power cycles.

              rcache[,on|off]  - [SCSI only] Gets/sets the 'Read Cache Disable' (RCE) bit.  'Off'
              value disables read cache (if supported).  The read cache  is  usually  enabled  by
              default.

              dsn[,on|off]  -  [ATA  only]  [NEW EXPERIMENTAL SMARTCTL FEATURE] Gets/sets the DSN
              feature (if supported).  The dsn is usually disabled by default.

       SMART READ AND DISPLAY DATA OPTIONS:

       -H, --health
              Prints the health status of the device or pending TapeAlert messages.

              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.

              [ATA]  Health  status  is obtained by checking the (boolean) result returned by the
              SMART RETURN STATUS command.  The return value of this ATA command may  be  unknown
              due  to  limitations  or  bugs  in  some  layer (e.g. RAID controller or USB bridge
              firmware) between disk and operating system.   In  this  case,  smartctl  prints  a
              warning  and  checks  whether  any Prefailure SMART Attribute value is less than or
              equal to its threshold (see '-A' below).

              [SCSI] Health status is obtained by checking the Additional Sense  Code  (ASC)  and
              Additional  Sense  Code Qualifier (ASCQ) from Informal Exceptions (IE) log page (if
              supported) and/or from SCSI sense data.

              [SCSI tape drive or changer] TapeAlert status is obtained by reading the  TapeAlert
              log  page.   Please  note  that  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 condition.

              [NVMe]  NVMe  status  is  obtained  by reading the "Critical Warning" byte from the
              SMART/Health Information log.

       -c, --capabilities
              [ATA] 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.

              [NVMe]  Prints  various  NVMe  device  capabilities  obtained  from  the   Identify
              Controller and the Identify Namespace data structure.

       -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 values printed by smartctl are sensible.
              For example the temperature Attribute generally has its  raw  value  equal  to  the
              temperature  in  Celsius.   However  in some cases vendors use unusual conventions.
              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 Normalized 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 actually 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 newer ATA/SATA disks
              seem to respect their meaning, so we have  retained  the  option  of  printing  the
              Attribute values.

              Solid-state drives use different meanings for some of the attributes.  In this case
              the attribute name printed by smartctl is incorrect unless the drive is already  in
              the smartmontools drive database.

              Note  that  the  ATA  command  SMART  READ  DATA was declared obsolete in ATA ACS-4
              Revision 10 (Nov 2015).

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

              [NVMe]  For  NVMe  devices  the  attributes  are  obtained  from  the  SMART/Health
              Information log.

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

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

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

              hex,id - Print all attribute IDs as hexadecimal numbers.

              hex,val - Print all normalized values as hexadecimal numbers.

              hex - Same as '-f hex,id -f hex,val'.

       -l TYPE, --log=TYPE
              Prints various device logs.  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) values 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  Command
              Register  (CR) and Feature Register (FR) values.  Commands that are obsolete in the
              most current 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 command 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-standard.

              The  ATA  Specification (ATA ACS-2 Revision 7, Section A.7.1) says: "Error log data
              structures shall include, but are not limited  to,  Uncorrectable  errors,  ID  Not
              Found  errors  for which the LBA requested was valid, servo errors, and write fault
              errors.  Error log data structures shall  not  include  errors  attributed  to  the
              receipt of faulty commands."  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 command, 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 smartmontools 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 specifications, 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.

              error[,NUM] - [NVMe] prints the NVMe Error  Information  log.   Only  the  16  most
              recent  log  entries  are  printed  by  default.  This number can be changed by the
              optional parameter NUM.  The maximum number of log entries is vendor  specific  (in
              the range from 1 to 256 inclusive).

              xerror[,NUM][,error] - [ATA only] prints the Extended Comprehensive 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.

              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 recent drives may report errors only in the Extended Comprehensive
              SMART  error  log.  The Summary SMART error log may be reported as supported but is
              always empty then.

              selftest - [ATA] prints the SMART self-test log.  The disk  maintains  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 successfully, 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.

              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 segment.  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 notation.  If provided, the SCSI Sense
              Key (SK), Additional Sense Code (ASC) and Additional Sense  Code  Qualifier  (ASCQ)
              are  also printed.  The self tests can be run using the '-t' option described below
              (using the ATA test terminology).

              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.

              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  carried  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).

              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 directory,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 periodically
              (e.g. every 24 hours) on recent SCSI disks.  If supported, the BMS status is output
              first,  indicating  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 mechanism 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 temperature and temperature ranges returned by the  SCT
              Status command, 'scttemphist' prints temperature limits and the temperature history
              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 ATA8-ACS and were also supported by 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/HGST) and ERC (as used by Seagate).
              READTIME 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] 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 ACS-2
              and is only supported by some recent devices.

              defects[,NUM] - [ATA only] [NEW EXPERIMENTAL SMARTCTL FEATURE] prints LBA and hours
              values  from  the ATA Pending Defects log (General Purpose Log address 0x0c).  Only
              the 31 entries from first log page are printed by  default.   This  number  can  be
              changed  by  the  optional parameter NUM.  The size of the log and the order of the
              entries are vendor specific.  The Pending  Defects  log  was  introduced  in  ACS-4
              Revision 01 (Mar 2014).

              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.  This also works for SATA devices
              with Packet interface like CD/DVD drives.

              sasphy[,reset] - [SAS (SCSI) only] prints values and descriptions 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 directory (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.

              nvmelog,PAGE,SIZE - [NVMe only] prints a hex dump of the first SIZE bytes from  the
              NVMe  log with identifier PAGE.  PAGE is a hexadecimal number in the range from 0x1
              to 0xff.  SIZE is a hexadecimal number in the range from 0x4 to  0x4000  (16  KiB).
              WARNING:  Do not specify the identifier of an unknown log page.  Reading a log page
              may have undesirable side effects.

              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...
              [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  specified  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 ordering.

              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  integers.   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  integer.   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.

              raw56 - Print the Raw value as a 54-bit unsigned base-10  integer.   This  includes
              the reserved byte which follows the 48-bit raw value.

              hex56  -  Print  the Raw value as a 14 digit hexadecimal number.  This includes the
              reserved byte which follows the 48-bit raw value.

              raw64 - Print the Raw value as a 64-bit unsigned base-10  integer.   This  includes
              two  bytes  from the normalized and worst attribute value.  This raw format is used
              by some SSD devices with Indilinx controller.

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

              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 seconds 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(raw8) - Print the raw attribute as a 24-bit value and  three  optional  8-bit
              values if these bytes are nonzero.  This is the default for Attribute 9.

              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  Sector  Count)  is  not  reset  if
              uncorrectable sectors are reallocated (see smartd.conf(5) man page).

              198,offlinescanuncsectorct - same as: 198,raw48,Offline_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,tempminmax,Temperature_Celsius.

       -F TYPE, --firmwarebug=TYPE
              [ATA  only]  Modifies  the  behavior  of  smartctl to compensate for some known and
              understood device firmware or driver bug.  This option may be used multiple  times.
              The valid arguments are:

              none  -  Assume that the device firmware obeys the ATA specifications.  This is the
              default, unless the device has presets for '-F' in the drive database.  Using  this
              option on the command line will override any preset values.

              nologdir  - Suppresses read attempts of SMART or GP Log Directory.  Support for all
              standard logs is assumed without an actual check.  Some Intel SSDs  may  freeze  if
              log address 0 is read.

              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 modifies the output of the  self-test  execution  status  (see
              options '-c' or '-a' above) accordingly.

              xerrorlba  -  Fixes  LBA  byte  ordering in Extended Comprehensive SMART error log.
              Some disks use little endian byte ordering instead  of  ATA  register  ordering  to
              specify the LBA addresses in the log entries.

              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 presets are used.

              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 smartmontools 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 override additional Attribute interpretation
              ('-v N,something') command-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 version.

       -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  /var/lib/smartmontools/drivedb/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  conjunction  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.

              All '-t TEST' commands can be given during normal system operation  unless  captive
              mode  ('-C' option) is used.  A running self-test can, however, degrade performance
              of the drive.  Frequent  I/O  requests  from  the  operating  system  increase  the
              duration of a test.  These impacts may vary from device to device.

              If a test failure occurs then the device may discontinue the testing and report the
              result immediately.

              [ATA] Note that the ATA command SMART EXECUTE OFF-LINE IMMEDIATE  (the  command  to
              start a test) was declared obsolete in ATA ACS-4 Revision 10 (Nov 2015).

              The valid arguments to this option are:

              offline  -  [ATA]  runs  SMART Immediate Offline Test.  This immediately 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" capability 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 minutes).  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
              automatic 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  to  several  hours).
              This  is a longer and more thorough version of the Short Self Test described above.
              Note that this command can be given during 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 (minutes).  This self-
              test routine is intended to identify damage incurred  during  transporting  of  the
              device.   This  self-test  routine 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/sda
                smartctl -t select,10+11 /dev/sda
              both  runs  a  self  test on one span consisting of LBAs ten to twenty (inclusive).
              The command:
                smartctl -t select,100000000-max /dev/sda
              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/sda
              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/sda
              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 several hours.  Selective self-tests
              are  helpful  if  (based  on  SYSLOG 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 identical 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/sda
                smartctl -t select,redo /dev/sda
                smartctl -t select,redo+20 /dev/sda
              have the same effect as:
                smartctl -t select,10-20 /dev/sda
                smartctl -t select,10-20 /dev/sda
                smartctl -t select,10-29 /dev/sda

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

              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 subcommand is specified as a  hex  value  in
              the  range  0x00  to  0xff.   Subcommands  0x40–0x7e and 0x90–0xff are reserved for
              vendor specific 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 some Intel 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.

              force  - start new self-test even if another test is already running.  By default a
              running self-test will not be interrupted to begin another test.

       -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 without 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 transports (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 equivalents.  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 equivalents 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 interactions 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,
       smartmontools  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/sda
       Print a large amount of SMART information for drive /dev/sda.

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

       smartctl --smart=on --offlineauto=on --saveauto=on /dev/sda
       Enable  SMART  on  drive  /dev/sda, 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/sdc
       Begin  an  extended  self-test of drive /dev/sdc.  You can issue this command 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/sda
       Enable  SMART on the disk, and begin an immediate offline test of drive /dev/sda.  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/sda
       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/sda
       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/sda
       Examine all SMART data for device /dev/sda, but produce no printed output.  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/twl0
       Examine  all  SMART  data for the first SATA (not SAS) disk connected to a 3ware RAID 9750
       controller card.

       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/sda
       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 minutes 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.

EXIT STATUS

       The exit statuses of smartctl are defined by a bitmask.  If all is well with the disk, the
       exit status (return value) 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 exit status 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 or other ATA 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 (which should work with  any  POSIX  compatible
       shell):
       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 shell script prints all status bits:
       val=$?; mask=1
       for i in 0 1 2 3 4 5 6 7; do
         echo "Bit $i: $(((val & mask) && 1))"
         mask=$((mask << 1))
       done

FILES

       /usr/sbin/smartctl
              full path of this executable.

       /var/lib/smartmontools/drivedb/drivedb.h
              drive database (see '-B' option).

       /etc/smart_drivedb.h
              optional local drive database (see '-B' option).

AUTHORS

       Bruce Allen (project initiator),
       Christian Franke (project manager, Windows port and all sort of things),
       Douglas Gilbert (SCSI subsystem),
       Volker Kuhlmann (moderator of support and database mailing list),
       Gabriele Pohl (wiki & development team support),
       Alex Samorukov (FreeBSD port and more, new Trac wiki).

       Many other individuals have made contributions and corrections, see AUTHORS, ChangeLog and
       repository files.

       The first smartmontools code was derived from the smartsuite package, written  by  Michael
       Cornwell and Andre Hedrick.

REPORTING BUGS

       To submit a bug report, create a ticket in smartmontools wiki:
       <https://www.smartmontools.org/>.
       Alternatively send the info to the smartmontools support mailing list:
       <https://listi.jpberlin.de/mailman/listinfo/smartmontools-support>.

SEE ALSO

       smartd(8).
       update-smart-drivedb(8).

REFERENCES

       Please see the following web site for more info: <https://www.smartmontools.org/>

       An  introductory article about smartmontools is Monitoring Hard Disks with SMART, by Bruce
       Allen,      Linux      Journal,      January      2004,      pages       74–77.        See
       <https://www.linuxjournal.com/article/6983>.

       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  revision  2  and  the
       SFF-8055i  revision  1.4 specifications.  These are publications 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 <https://www.smartmontools.org/wiki/Links>.

PACKAGE VERSION

       smartmontools-7.0 2018-12-30 r4883
       $Id: smartctl.8.in 4882 2018-12-29 21:26:45Z chrfranke $