Provided by: smartmontools_7.1-1build1_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 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] - 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.

              jmb39x,N[,sLBA][,force][+TYPE] - [NEW EXPERIMENTAL  SMARTCTL  FEATURE]  the  device
              consists of multiple SATA disks connected to a JMicron JMB39x RAID port multiplier.
              The integer N is the port number from 0 to 4.
              WARNING: The ATA pass-through commands are issued via READ/WRITE commands to LBA 33
              of  the  RAID  volume.   Using  this  option  with other devices may overwrite this
              sector.
              The LBA could be selected in the range 33 (last sector of a GPT) to 62 (last sector
              of traditional boot area).
              By  default,  access  to  the  device is refused if the selected sector is not zero
              filled.  The 'force' flag disables this check.
              WARNING: Orignal sector data is not written back if  smartctl  is  aborted  with  a
              signal.

       -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).  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.  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] 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.  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]  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] 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-7.1 2019-12-30 r5022
       $Id: smartctl.8.in 5018 2019-12-29 13:37:25Z chrfranke $