Provided by: sdparm_1.12-1_amd64 bug


       sdparm - access SCSI modes pages; read VPD pages; send simple SCSI commands.


       sdparm  [--all] [--dbd] [--examine] [--flexible] [--get=STR] [--hex] [--long] [--num-desc]
       [--out-mask=OM]  [--page=PG[,SPG]]   [--quiet]   [--readonly]   [--six]   [--transport=TN]
       [--vendor=VN] [--verbose] DEVICE [DEVICE...]

       sdparm  [--clear=STR]  [--defaults]  [--dummy]  [--flexible]  [--page=PG[,SPG]]  [--quiet]
       [--readonly]  [--save]  [--set=STR]  [--six]  [--transport=TN]  [--vendor=VN]  [--verbose]
       DEVICE [DEVICE...]

       sdparm --command=CMD [--hex] [--long] [--readonly] [--verbose] DEVICE [DEVICE...]

       sdparm  --inquiry  [--all] [--examine] [--flexible] [--hex] [--num-desc] [--page=PG[,SPG]]
       [--quiet] [--readonly] [--transport=TN] [--verbose] DEVICE [DEVICE...]

       sdparm  --enumerate  [--all]  [--inquiry]  [--long]   [--page=PG[,SPG]]   [--transport=TN]

       sdparm  --inhex=FN  [--all]  [--flexible]  [--hex] [--inquiry] [--long] [--pdt=DT] [--raw]
       [--six] [--transport=TN] [--vendor=VN] [--verbose]

       sdparm --wscan [--verbose]

       sdparm [--help] [--version]


       This utility fetches and potentially changes SCSI device (e.g. disk) mode  pages.  Inquiry
       data  including  Vital Product Data (VPD) pages can also be displayed. Commands associated
       with starting and stopping the  medium;  loading  and  unloading  the  medium;  and  other
       housekeeping functions may also be issued by this utility.

       The  first  invocation  shown  in  the  synopsis is for accessing (i.e. reading) mode page
       fields held on the DEVICE. The second form is for changing mode page fields  held  on  the
       DEVICE.  The  third form is for executing some simple SCSI commands. The fourth form (i.e.
       the '--inquiry ...  DEVICE' form) is for fetching and decoding VPD pages  from  the  given
       DEVICE.  The  --enumerate  form  is  for  listing  out mode or VPD field data held by this
       utility (and if a DEVICE is given then it is ignored). The --inhex=FN form decodes mode or
       VPD  response  data provided in the named file (or from stdin if FN=- is given); that data
       may either be in hexadecimal or binary. The second last form is for Windows only and lists
       the  available  storage device names; see the OPTIONS entry for --wscan. The final form is
       to provide command line help or the version number (and date) of this utility.

       If no options (other than DEVICE) are given then a selection of common  mode  page  fields
       for  that  device are listed. If the --long option is also given then a description of the
       fields is placed on the right of each line. If the --all option is given  then  all  known
       mode  page  fields for that device are listed. Individual fields can be displayed with the
       --get=STR option (e.g. '--get=WCE' to fetch  the  state  of  the  Writeback  Cache  Enable

       This  utility completes with an exit status of 0 when successful. For other values see the
       EXIT STATUS section below.

       One or more DEVICE arguments can be given. The utility will essentially  apply  the  given
       options  to  each  DEVICE in the list. If a error is detected, it is noted and the utility
       continues. Error value 5 (file open or close problem) is treated as  lower  priority  when
       other  errors  are  detected.  The  exit  status is the most recently detected error value
       (excluding error value 5 if other errors have been detected). If all actions  succeed  the
       exit status is zero.

       By default this utility shows mode pages that are common to all transport protocols. These
       are termed as "generic" mode pages. If there is no match on a generic mode  page  name  or
       field  then  those  pages  specific  to the SAS transport are checked.  Transport protocol
       specific mode pages are selected with the --transport=TN option. See the TRANSPORT section
       below.   Vendor  specific  mode  pages  are selected with the --vendor=VN option.  See the
       VENDORS section below.

       Although originally for SCSI disks (or storage devices that  appear  to  the  OS  as  SCSI
       disks)  many  of  the  mode  pages  are for other SCSI device types.  These include CD/DVD
       players that use  the  ATAPI  (or  any  other)  transport,  SCSI  tapes  drives  and  SCSI

       When  the  --inquiry  option is given without a page number then the Device Identification
       VPD page (page number 0x83) is requested and if found it is decoded and output. If no page
       number is given and the --all option is given then a list of VPD page names (but not their
       contents) supported by the DEVICE is output. When both the --inquiry and --page=PG options
       are  given  then  the VPD page can be specified as an abbreviation (e.g. "sp" for the SCSI
       ports VPD page) or numerically (e.g. "0x88"). If a VPD page is returned by the DEVICE  but
       sdparm cannot decode it or the --hex option is given then it is output in hex.


       Mandatory arguments to long options are mandatory for short options as well.  If an option
       takes a numeric argument then that argument is assumed  to  be  decimal  unless  otherwise
       indicated  (e.g.  with  a leading "0x" or a trailing "h"). The options are in alphabetical
       order, based on the long option name.

       -a, --all
              output all recognized fields for the device type (e.g. disk) of the DEVICE. Without
              this  option  (or  the  --page=PG[,SPG]  option)  the default action is to output a
              relatively small number of commonly  used  fields  from  different  pages.  When  a
              specific  (mode)  page number is given with the --page=PG[,SPG] option then all the
              fields of that page are output (irrespective of the setting of  this  option).  For
              this  option's  action  when  used  with  the  --enumerate option see the ENUMERATE
              section below.
              When used together with the --inquiry option and a DEVICE, the Supported VPD  Pages
              VPD  page [0x0] is output. When this option is used twice (short form: '-iaa') then
              all VPD pages (listed in the Supported VPD Pages VPD page) are output.
              By default --inhex=FN will only decode the first mode page found in FN.  With  this
              option,  more  mode  pages  will  be  decoded  if  present.  When --transport=TN or
              --vendor=VN is also given then if a  given  mode  page  is  not  defined  for  that
              transport or vendor, then it is decoded as a generic mode page.

       -c, --clear=STR
              In  its  simplest  form  STR  contains  a  field  acronym_name or a field numerical
              descriptor. In the absence of an explicit value  argument  (e.g.  '--clear=WCE=1'),
              the field has its value cleared to zero.  See the PARAMETERS section below.

       -C, --command=CMD
              Perform  given  CMD. See section below on COMMANDS. To enumerate supported commands
              use '-e -C x' (using any CMD name, valid or otherwise).

       -B, --dbd
              disable block descriptors. This is a bit in MODE SENSE cdbs that rarely needs to be
              set.  One  known  case  is  a MODE SENSE 6 issued to a Reduced Block Commands (RBC)
              device where the RBC standard says it shall be set.

       -D, --defaults
              sets the given mode page to its default values. Requires the --page=PG[,SPG] option
              to be given to specify the mode page. To make the default mode page values also the
              saved mode page values, use the --save option as well.
              when this option is used twice, the current values in all modes pages are  reverted
              to  their  defaults.  If  the  --save option is given as well, then the current and
              saved values in all modes pages are reverted to their defaults. This  feature  uses
              the RTD bit in the MODE SELECT command which was added in draft SPC-5 revision 11.

       -d, --dummy
              when set inhibits changes being placed in the DEVICE's mode page.  Instead the mode
              data that would have been sent to a MODE SELECT command, is output in ASCII hex  to
              the console. This option is mainly for testing.

       -e, --enumerate
              lists out descriptive information about the pages and fields known to this utility.
              Ignores the DEVICE argument and other options  apart  from  the  --all,  --inquiry,
              --long,  --page=PG[,SPG],  --transport=TN  and --vendor=VN. If --enumerate is given
              without other options then the known (generic) mode  pages  are  listed.   See  the
              ENUMERATE section below.

       -E, --examine
              for  mode  pages only those with known field names are probed when the --all option
              is given. For VPD pages only those pages listed in "Supported VPD pages  page"  are
              decoded.  In both cases some pages may be missed. With this option (i.e. --examine)
              all mode and VPD pages can be probed.
              For mode pages, this option will probe all mode pages from page number 0x0 to 0x3e.
              To probe mode subpages give a mode page number with --page=PG and then all subpages
              (from 0x0 to 0xfe) are probed.
              For VPD pages, use this option with --inquiry. This will cause all VPD  pages  from
              0x0  to  0xbf  to  be probed by default. A sequence of VPD pages can be probed with
              --page=PG[,SPG] in which case VPD pages from PG (lower number) to SPG (high number)
              inclusive  are  probed.  Vendor specific VPD pages run from 0xc0 to 0xff and can be
              probed by setting SPG from 0xc0 to 0xff.

       -f, --flexible
              Some devices, bridges and/or drivers attempt  crude  transformations  between  mode
              sense  6 and 10 byte commands without correctly rebuilding the response.  This will
              cause the response to be mis-interpreted (usually with an error saying the response
              is  malformed).  With this option, the length of the response is checked, and if it
              looks wrong, various corrections are attempted. This option will  also  allow  mode
              pages that don't belong to the current device's peripheral type to be listed.

       -g, --get=STR
              In  its  simplest  form  STR  contains  a  field  acronym_name or a field numerical
              descriptor. The field is fetched from mode page. See the PARAMETERS section  below.
              The  --long  and  --hex options effect the output format. Also if a value of "1" is
              given (e.g. '--get=WCE=1') only the current value is output (i.e.  not  the  change
              mask, the default value and the saved value).

       -h, --help
              output the usage message then exit.

       -H, --hex
              rather  than trying to decode mode (or VPD) pages, print them out in hex. When used
              with the --get=STR option the corresponding current, changeable, default and  saved
              values  are  output in hex, prefixed by "0x" and space separated. If a value of "1"
              is given with the --get=STR option (e.g. '--get=WCE=1') then only the current value
              is  output  in hex, prefixed by "0x". If a value of "2" is given with the --get=STR
              option then only the current value is output as a (signed) integer. This option can
              be used multiple times (e.g. '-HH'). Useful with the ATA Information VPD page which
              usually outputs its IDENTIFY (PACKET) DEVICE response in 16  bit  hex  words;  with
              '-HH'  outputs that response in hex bytes; with '-HHH' outputs the same response in
              a format suitable for 'hdparm --Istdin' to decode.
              Mode page output with the '-HHH' option is  suitable  for  a  later  invocation  of
              sdparm with the --inhex=FN option.

       -i, --inquiry
              output  a  VPD  page  which  is  in  the response of a SCSI INQUIRY command sent to
              DEVICE. In the absence of this option the default action is to output  mode  pages.
              If the --inquiry option is given without the --page=PG[,SPG] option then the device
              identification VPD page (0x83) is decoded and output. If this option and the  --all
              option are given then the supported VPD pages page (0x0) is decoded and output.

       -I, --inhex=FN
              FN  is  expected  to  be  a  file  name  (or  '-'  for  stdin) which contains ASCII
              hexadecimal (or binary) representing the response to MODE SENSE(10).  If  --six  is
              also  given  then the response from MODE SENSE(6) is assumed. A MODE SENSE response
              contains a mode parameter header, then 0 or more block descriptors followed by  one
              or  more  mode  pages. This utility will only decode the first mode page unless the
              --all option is given. In order to decode a mode page the peripheral device type is
              often  needed  and can be supplied with the --pdt=DT option. If the --pdt=DT is not
              given then a mode page found in two device type standards (e.g. SBC and SSC) may be
              decoded twice.
              If  --inquiry  is given then FN is interpreted as the response data of a single VPD
              The hexadecimal in FN should be arranged as 1 or 2 digits representing a byte  each
              of  which is whitespace or comma separated. Anything from and including a hash mark
              to the end of line is ignored. If the --raw option is given then FN is  treated  as

       -l, --long
              output extra information. In the case of mode page fields a description (with units
              if applicable) is output to the right. If used twice, then  for  some  fields  more
              information about its values is given on one or more following lines, each prefixed
              by a tab character. For usage with --enumerate see the ENUMERATE section below.
              When this option is used along with --command=capacity then the  READ  CAPACITY(16)
              is sent to the DEVICE and if successful its extended response is output.

       -n, --num-desc
              for  a mode page that can have descriptors, the number of descriptors for the given
              page on the DEVICE is output. Otherwise 0 is output.

       -o, --out-mask=OM
              OM is a bit mask for mode page selections that will  be  printed/output.   The  0x1
              value  is  for the 'current' values, 0x2 is for the 'changeable' values, 0x4 is for
              the 'default' values and 0x8 is for the 'saveable' values.  The  default  value  is
              0xf  (i.e.  the  OR  of all four values set). The option is useful for limiting the
              amount of output with the '-HHH'.

       -p, --page=PG[,SPG]
              supply the page number (PG) and optionally the sub page number (SPG)  of  the  mode
              (or  VPD)  page  to fetch. These numbers are interpreted as decimal unless prefixed
              with "0x" or a trailing. Sub page numbers are only valid for mode  pages  (not  VPD
              pages). Alternatively an abbreviation for a page can be given (see next entry).

       -p, --page=STR
              a  two  or  three  letter  abbreviation  for  a  page can be given. Known mode page
              abbreviations are checked first followed by  known  VPD  page  abbreviations.   For
              example  '--page=ca'  matches  the  caching mode page. If no match is found then an
              error is issued and a list of possibilities in the current context is given (so '-p
              x'  can be quite useful). If the STR matches a known VPD page abbreviation then the
              --inquiry option is assumed. For usage with --enumerate see the  ENUMERATE  section

       -P, --pdt=DT
              This  option  is  only  active  when  the  --inhex=FN  option  is given.  DT is the
              peripheral Device Type, a value between 0 and 31 and can be found in  the  response
              to  the  INQUIRY  command. The default value is -1 (which may also be given for DT)
              and it is interpreted as SPC (i.e. common  mode  pages)  or  as  a  wild  card.  If
              available this option should be supplied with the --inhex=FN option.

       -q, --quiet
              suppress output of device name followed by the vendor, product and revision strings
              fetched from an INQUIRY response. Without this option such a line is typically  the
              first  line  output  by  sdparm.  Reduces output from the device identification VPD
              page, typically to one line (or none) for each of  di_lu,  di_port,  di_target  and
              If  this  option  is  used  twice then additionally mode page output suppresses the
              changeable, default  and  saved  values  that  are  usually  shown  in  braces,  if

       -r, --readonly
              override  other  logic to open DEVICE in read-only mode. The default setting of the
              open read-only/read-write mode depends on the operation requested (e.g. a --set=STR
              operation by default will try a read-write mode open on DEVICE). This option may be
              useful if a command is being sent to an ATA  disk  via  a  SCSI  command  set.  For
              example  in  Linux  '-C  stop'  may  require  this option to stop an ATA disk being
              restarted immediately.

       -R, --raw
              this option is only active when used with the --inhex=FN option.  When this  option
              is  given  then the file FN is interpreted as binary; the default action (i.e. when
              this option is not given) is to interpret FN as ASCII hexadecimal.

       -S, --save
              when a mode page is being modified  (by  using  the  --clear=STR  and/or  --set=STR
              options)  then  the  default action is to modify only the current values mode page.
              When this option is given then the corresponding value(s) in the saved values  mode
              page is also changed. The next time the device is power cycled (or reset) the saved
              values mode page becomes (i.e. is copied to) the current  values  mode  page.  This
              option sets the SP field in the MODE SELECT command. See NOTES section below.

       -s, --set=STR
              in  its  simplest  form  STR  contains  a  field  acronym_name or a field numerical
              descriptor. In the absence of an explicit value, each acronym_name  has  its  value
              set  to  (all) ones. This means a 16 bit field will be set to 0xffff which is 65535
              in decimal. Alternatively each acronym_name or numerical descriptor may be followed
              by  "=<n>"  where <n> is the value to set that field to. See the PARAMETERS section

       -6, --six
              The default action of this utility is to issue MODE  SENSE  and  MODE  SELECT  SCSI
              commands  with  10 byte cdbs. When this option is given the 6 byte cdb variants are
              used. RBC and old SCSI devices  may  need  this  option.  This  utility  outputs  a
              suggestion  to  use  this  option if the SCSI status indicates that the 10 byte cdb
              variant is not supported.
              The SPC-4 standard (and SPC-5 drafts) include  a  note  stating  that  implementers
              migrate  away  from the SCSI MODE SELECT(6) and MODE SENSE(6) commands in favour of
              the 10 byte variants (e.g.  MODE SEMSE(10)).

       -t, --transport=TN
              Specifies the transport protocol where TN is either a number in the range 0  to  15
              (inclusive)  or  an  abbreviation (e.g. "fcp" for the Fibre Channel Protocol). Some
              transports accept multiple abbreviations, for example srp (SCSI RDMA Protocol)  and
              ib  (short for InfiniBand) both are accepted for transport protocol 0x4 . Also both
              upper and lower case are accepted so iscsi and iSCSI  are  accepted  for  transport
              protocol  0x5  .  One  way  to list available transport protocols numbers and their
              associated abbreviations is to give an invalid transport protocol name such as  '-t
              x';  another way is '-e -l'.  N.B. The --all option may still be needed to show all
              available fields.

       -M, --vendor=VN
              Specifies the vendor (i.e. manufacturer) where VN is either a number (0 or more) or
              an  abbreviation  (e.g.  "sea"  for Seagate disk vendor specific).  For tape drives
              "lto5" and "lto6" are treated as vendors. One way  to  list  the  available  vendor
              numbers and their associated abbreviations is to give an invalid vendor number such
              as '-M x'; another way is '-e -l'.
              This option only effects mode page decodes, not VPD pages. For vendor specific  VPD
              pages see the sg_vpd utility.

       -v, --verbose
              increase  the  level of verbosity, (i.e. debug output). In some cases more decoding
              is done (e.g. fields within a standard INQUIRY response).

       -V, --version
              print the version string and then exit.

       -w, --wscan
              this option is available in Windows only. It lists storage  device  names  and  the
              corresponding  volumes,  if  any.  When  used  twice  it adds the "bus type" of the
              closest transport (e.g. a SATA disk in a USB connected enclosure has bus type Usb).
              When  used  three  times  a SCSI adapter scan is added. When used four times only a
              SCSI adapter scan is shown.  See examples below and the "Win32 port" section in the
              README file.


       The  reference document used for interpreting mode and VPD pages (and the INQUIRY standard
       response) is  T10/BSR  INCITS  502  Revision  17  (SPC-5,  19  September  2017)  found  at  .  Obsolete and reserved items in the standard INQUIRY response output
       are displayed in brackets. Recent drafts of other  T10  documents  are  also  used:  SBC-4
       (disks), SSC-5 (tapes), SPL-5 (SAS transport) and SAT-4 (SCSI to ATA Translation).

       A  mode  page for which no abbreviation is known (e.g. a vendor specific mode page) can be
       listed in hexadecimal by using the option combination '--page=PG --hex'.

       Numbers input to sdparm (e.g. in the command line arguments) are assumed to be in  decimal
       unless  there is a hexadecimal indicator. A hexadecimal indicator is either a leading '0x'
       or '0X' (i.e. the C language convention) or a trailing 'h' or  'H'  (i.e.  the  convention
       used  at  ). In the case of --page= either a string or number is expected, so
       hex numbers like 'ch' (12) should be prefixed by a zero (e.g. '0ch').

       The SPC-4 draft (rev 2) says that devices that implement no  distinction  between  current
       and  saved pages can return an error (ILLEGAL REQUEST, invalid field in cdb) if the SP bit
       (which corresponds to the --save option) is _not_ set. In such  cases  the  --save  option
       needs to be given.

       If  the  --save option is given but the existing mode page indicates (via its PS bit) that
       the page is not saveable, then this utility  generates  an  error  message.  That  message
       suggests to try again without the --save option.

       Since the device identification VPD page (acronym_name "di") potentially contains a lot of
       diverse designators, several associated acronyms  are  available.  They  are  "di_lu"  for
       designators  associated  with  the  addressed  logical  unit,  "di_port"  for  designators
       associated with the target port (which  the  command  arrived  via)  and  "di_target"  for
       designators  associated  with the target device. When "di" is used designators are grouped
       by lu, then port and then target device.  To see all designators decoded in the order that
       they appear in the VPD page use "di_asis".

       Only  those VPD pages defined by are decoded by this utility. SPC-4 sets aside VPD
       pages codes from 0xc0 to 0xff (inclusive) for vendor specific  pages  some  of  which  are
       decoded in the sg_vpd utility.

       To see all VPD pages supported by a DEVICE use 'sg_vpd --all'.

       In  the  linux kernel 2.6 and 3 series any device node that understands a SCSI command set
       (e.g. SCSI disks and CD/DVD drives) may be  specified.  More  precisely  the  driver  that
       "owns"  the  device  node  must  support  the  SG_IO ioctl. In the lk 2.4 series only SCSI
       generic (sg) device nodes support the SG_IO ioctl. However in the lk 2.4 series other SCSI
       device  nodes are mapped within this utility to their corresponding sg device nodes. So if
       there is a SCSI disk at /dev/sda then 'sdparm /dev/sda' will  work  in  both  the  lk  2.4
       series  and  later.  However  if  there  is an ATAPI cd/dvd drive at /dev/hdc then 'sdparm
       /dev/hdc' will only work in the lk 2.6 series and later.

       In the Linux 2.6 and 3 series, especially with ATA disks, using sdparm to stop (spin down)
       a  disk  may  not  be  sufficient and other mechanisms will start the disk again some time
       later. The user might additionally mark  the  disk  as  "offline"  with  'echo  offline  >
       /sys/block/sda/device/state'  where sda is the block name of the disk. To restart the disk
       "offline" can be replaced with "running".


       In their simplest form the --clear=, --get= and --set= options (or their short forms) take
       an  acronym_name  such  as "WCE". In the case of '--get=WCE' the value of "Writeback Cache
       Enable" in the caching mode page will be fetched. In the case of '--set=WCE' that bit will
       be  set (to one). In the case of '--clear=WCE' that bit will be cleared (to zero). When an
       acronym_name is given then the mode page is imputed from that acronym_name (e.g. WCE is in
       the caching mode page).

       Instead  of an acronym_name a field within a mode page can be described numerically with a
       <start_byte>:<start_bit>:<num_bits> tuple. These are the <start_byte>  (origin  0)  within
       the  mode  page,  a <start_bit> (0 to 7 inclusive) and <num_bits> (1 to 64 inclusive). For
       example, the low level representation of the RCD bit (the "Read Cache Disable bit  in  the
       caching  mode  page)  is  "2:0:1".  The  <start_byte> can optionally be given in hex (e.g.
       '--set=0x2:0:1' or '--set=2h:0:1'). With this form  the  --page=  option  is  required  to
       establish which mode page is to be used.

       Either form can optionally be followed by "=<val>". By default <val> is decimal but can be
       given in hex in the normal fashion. Here are  some  examples:  '--set=2h:0:1=1h'  and  '-s
       MRIE=0x3'.  When  the  acronym_name  or  numeric  form  following --clear= is not given an
       explicit '=<val>' then the value defaults to zero. When the acronym_name or  numeric  form
       following  --set=  is not given an explicit '=<val>' then the value defaults to "all ones"
       (i.e. as many as <num_bits> permits). For example '--clear=WCE' and  '--clear=WCE=0'  have
       the same meaning: clear Writeback Cache Enable or, put more simply: turn off the writeback

       Multiple fields within the same mode page can be changed by giving a comma separated  list
       of acronym_names and/or the numerical form. For example: '--set=TEST,MRIE=6'.

       Some  mode  page  have multiple descriptors. They typically have a fixed header section at
       the start of the mode page that includes a field containing the number of descriptors that
       follow.  Following  the  header is a variable number of descriptors. An example is the SAS
       Phy Control and Discover mode page. An acronym_name may include a trailing '.<num>'  where
       "<num>"  is  a descriptor number (origin 0). For example '-t sas -g PHID.0' and '-t sas -g
       PHID' will yield the phy identifier of the first descriptor of the above  mode  page;  '-t
       sas -g PHID.1' will yield the phy identifier of the second descriptor.


       The  --enumerate  option  essentially dumps out static information held by this utility. A
       list of --enumerate variants and their actions follows. For brevity subsequent examples of
       options are shown in their shorter form.

           --enumerate          list generic mode page information
           -e --all             list generic mode page contents
                                (i.e. parameters)
           -e --page=rw         list contents of read write error
                                recovery mode page
           -e --inquiry         list VPD pages this utility can decode
           -e --long            list generic mode pages, transport
                                protocols, mode pages for each
                                supported transport protocol and
                                supported commands
           -e -l --all          additionally list the contents of
                                each mode page
           -e --transport=fcp   list mode pages for the fcp
                                transport protocol
           -e -t fcp --all      additionally list the contents of
                                each mode page
           -e --vendor=sea      list vendor specific mode pages for
                                "sea" (Seagate)
           -e -M sea --all      additionally list the contents of vendor
                                specific mode pages for "sea" (Seagate)
           -e -p pcd -l         list contents of SAS phy control and
                                discovery mode page plus (due to "-l")
                                some descfriptor format information

       When known mode pages are listed (via the --enumerate  option) each line starts with a two
       or three letter abbreviation. This is followed by the page  number  (in  hex  prefixed  by
       "0x")  optionally followed by a comma and the subpage number. Finally the descriptive name
       of the mode page (e.g. as found in SPC-4) is output.

       When known parameters (fields) of a mode page are listed, each line starts with an acronym
       (indented  a  few spaces). This will match (or be an acronym for) the description for that
       field found in the (draft)  standards.  Next  are  three  numbers,  separated  by  colons,
       surrounded  by  brackets.  These  are  the  start  byte  (in hex, prefixed by "0x") of the
       beginning of the field within the mode page; the starting bit (0 through 7 inclusive)  and
       then  the  number of bits. The descriptive name of the parameter (field) is then given. If
       appropriate the  descriptive  name  includes  units  (e.g.  "(ms)"  means  the  units  are
       milliseconds).  Adding  the '-ll' option will list information about possible field values
       for selected mode page parameters.

       Mode parameters for which the num_bits is  greater  than  1  can  be  viewed  as  unsigned
       integers.  Often  16  and 32 bit fields are set to 0xffff and 0xffffffff respectively (all
       ones) which usually has a special meaning (see drafts). This utility outputs  such  values
       as  "-1"  to save space (rather than their unsigned integer equivalents). "-1" can also be
       given as the value to a mode page field acronym (e.g. '--set=INTT=-1'  sets  the  interval
       timer field in the Informational Exceptions control mode page to 0xffffffff).


       SCSI  transport  protocols are a relatively specialized area that can be safely ignored by
       the majority of users.

       Some transport protocols  have  protocol  specific  mode  pages.  These  are  usually  the
       disconnect-reconnect  (0x2),  the  protocol  specific logical unit (0x18) and the protocol
       specific port (0x19) mode pages. In some cases the latter mode page has several  subpages.
       The  most  common  transport protocol abbreviations likely to be used are "fcp", "spi" and

       Many of the field names are re-used in the same position so  the  acronym_name  namespaces
       have  been  divided between generic mode pages (i.e. when the --transport= option is _not_
       given) and a namespace for each transport  protocol.  A  LUPID  field  from  the  protocol
       specific  logical  unit  (0x18)  mode  page and the PPID field from protocol specific port
       (0x19) mode page are included in the generic  modes  pages;  this  is  so  the  respective
       (transport)  protocol  identifiers  can be seen. In most cases the user will know what the
       "port" transport is (i.e. the same transport as the HBA in the computer) but  the  logical
       unit's transport could be different.


       SCSI  leaves  a  lot  of space for vendor specific information. Often this is described in
       product manuals. The --vendor=VN (or -M=VN) option allows known vendor specific mode pages
       to be examined and/or modified by acronym.

       In  this utility the syntax and semantics of vendor specific mode pages is very similar to
       those of transport protocol specific mode pages. Both cannot be specified together. Vendor
       specific  modes  pages  can  still  be  accessed  numerically  (as shown at the end of the
       EXAMPLES section).


       The command option sends a SCSI command to the DEVICE. If the command fails then  this  is
       reflected in the non-zero exit status.  To obtain more information about the error use the
       -v option.

              sends a READ CAPACITY(10) command (valid for disks and cd/dvd media) by default. If
              successful  yields  "blocks:  " [the number of blocks], "block_length: " [typically
              either 512 or 2048] and "capacity_mib:  "  [capacity  in  MibiBytes  (1048576  byte

       If  the  number  of  blocks  is  too  large  to  fit  in the 4 byte field provided by READ
       CAPACITY(10) or, the --long option is given, then the READ CAPACITY(16) command  is  sent.
       If  the  --long  option  is  given,  then  the extra fields found in the READ CAPACITY(16)
       response are output.

       eject  stops the medium and ejects it from the device.  Note that ejection (by command  or
              button)  may  be  prevented  in  which  case  the 'unlock' command may be useful in
              extreme cases.  Typically only appropriate for cd/dvd drives and disk  drives  with
              removable  media.  Objects if sent to another peripheral device type (but objection
              can be overridden with '-f' option).

       load   loads the medium and starts  it  (i.e.  spins  it  up).  See  'eject'  command  for
              supported device types.

              lists  the various formats that a CD/DVD/HD-DVD/BD drive supports. These are called
              "profiles" in the MMC standard. The profiles are listed one per line.  If media  is
              in  the  drive  then  the profile that matches the media (if any) has an "*" to the
              right of the line.

       ready  sends the "Test Unit Ready" SCSI command to the DEVICE. No error is reported if the
              device  will  respond  to  data requests (e.g. READ) in a reasonable timescale. For
              example, if a disk is stopped then it will report "not ready". All  devices  should
              respond to this command.

       sense  sends a REQUEST SENSE command. It reports a hardware threshold exceeded, warning or
              low power condition if flagged. If a progress indication is present (e.g. during  a
              format) then it will be output as a percentage. Yields a process status of 0 if the
              command succeeds and the sense key is 0; else yields 1. The --quiet option  can  be
              used to lessen output, and --hex to output sense data in hex.

              permits the speed of a CD, DVD, HD_DVD or BD disc in a drive to be set (or at least
              influenced). It has this format: --command=speed=SPEED where SPEED is in  kilobytes
              per  second.  In this case a kilobyte is 1000 bytes. The "times one" speed for a CD
              is 176.4 kB/s, for a DVD is 1350 kB/s and for both HD-DVD and BD it is  4500  kB/s.
              If SPEED is zero then the drive is set to the speed that it considers gives optimal
              performance.  This command sends a SET STREAMING multi-media command (MMC)  to  the
              drive.   The  EXACT  bit  is  clear  so  the  drive  will  round the given SPEED as
              necessary.  The command is designed to control  read  speed;  setting  write  speed
              should be left to "burning" programs.

       start  starts  the medium (i.e. spins it up). Harmless if medium has already been started.
              See 'eject' command for supported device types. If the DEVICE is  an  ATA  disk  in
              Linux the '--readonly' option may be required.

       stop   stops the medium (i.e. spins it down). Harmless if medium has already been stopped.
              See 'eject' command for supported device types. If the DEVICE is  an  ATA  disk  in
              Linux the '--readonly' option may be required. See the NOTES section above.

       sync   sends  a  SYNCHRONIZE  CACHE  command. The device should flush any data held in its
              (volatile) buffers to the media.

       unlock tells a device to allow medium removal. It uses  the  SCSI  "prevent  allow  medium
              removal"  command.  This  is  desperation  stuff,  possibly overriding a prevention
              applied by the OS on a mounted file system. The "eject" utility (from  the  "eject"
              package)  is  more  graceful  and  should  be  tried  first.  This  command is only
              appropriate for devices with removable media.

       For loading and ejecting tapes the mt utility should be used (i.e.  not  these  commands).
       The 'ready' command is valid for tape devices.


       To list the common (generic) mode parameters of a disk:

          sdparm /dev/sda

       To list the designators within the device identification VPD page of a disk:

          sdparm --inquiry /dev/sda

       To see all parameters for the caching mode page:

          sdparm --page=ca /dev/sda

       To see all parameters for the caching mode page with parameter descriptions to the right:

          sdparm --page=ca --long /dev/sda

       To get the WCE values (current changeable default and saved) in hex:

          sdparm -g WCE -H /dev/sda
       0x01 0x00 0x01 0x01

       To get the WCE current value in hex:

          sdparm -g WCE=1 -H /dev/sda

       To set the "Writeback Cache Enable" bit in the current values page:

          sdparm --set=WCE /dev/sda

       To set the "Writeback Cache Enable" bit in the current and saved values page:

          sdparm --set=WCE --save /dev/sda

       To set the "Writeback Cache Enable" and clear "Read Cache Disable":

          sdparm --set=WCE --clear=RCD --save /dev/sda

       The previous example can also by written as:

          sdparm -s WCE=1,RCD=0 -S /dev/sda

       To re-establish the manufacturer's defaults in the current and saved values of the caching
       mode page:

          sdparm --page=ca --defaults --save /dev/sda

       If an ATAPI cd/dvd drive is at /dev/hdc then its common (mode) parameters could be  listed
       in the lk 2.6 and 3 series with:

          sdparm /dev/hdc

       If  there  is  a DVD in the drive at /dev/hdc then it could be ejected in the lk 2.6 and 3
       series with:

          sdparm --command=eject /dev/hdc

       If the ejection is being prevented by software then that can be overridden with:

          sdparm --command=unlock /dev/hdc

       One disk vendor has a "Performance Mode" bit (PM) in the vendor  specific  unit  attention
       mode page [0x0,0x0]. PM=0 is server mode (the default) while PM=1 is desktop mode. Desktop
       mode can be set (both current and saved values) with:

          sdparm --page=0 --set=2:7:1=1 --save /dev/sda

       The resultant change can be viewed in hex with the --hex option as there are  no  acronyms
       for vendor extensions yet. The PM bit is now covered by vendor specific mode pages and the
       above can also be accomplished with:

          sdparm --vendor=sea --set=PM --save /dev/sda

       What follows are some examples from Windows using the '--wscan' option.  The  idea  is  to
       list the storage device names on the system that might be invoked by other uses of sdparm.

         # sdparm --wscan
       PD0     [C]     FUJITSU   MHY2160BH         0000
       PD1     [DF]    WD        2500BEV External  1.05  WD-WXE90
       CDROM0  [E]     MATSHITA DVD/CDRW UJDA775  CB03

       So 'sdparm -a CDROM0' and 'sdparm -a E' will show all the (known) mode page fields for the
       Matshita DVD/CD drive. By using the '--wscan' option twice, the bus type (as seen  by  the
       OS) is added to the output:

         # sdparm -ww
       PD0     [C]     <Ata  >  FUJITSU   MHY2160BH         0000
       PD1     [DF]    <Usb  >  WD        2500BEV External  1.05  WD-WXE90
       CDROM0  [E]     <Atapi>  MATSHITA DVD/CDRW UJDA775  CB03

       And  the  pattern  continues  to  add a SCSI adapter scan. This may be useful if there are
       specialized storage related devices (e.g. a SES device in an enclosure) but does add  much
       extra information in this case.

         # sdparm -www
       PD0     [C]     <Ata  >  FUJITSU   MHY2160BH         0000
       PD1     [DF]    <Usb  >  WD        2500BEV External  1.05  WD-WXE90
       CDROM0  [E]     <Atapi>  MATSHITA DVD/CDRW UJDA775  CB03

       SCSI0:0,0,0   claimed=1 pdt=0h  FUJITSU   MHY2160BH         0000
       SCSI1:0,0,0   claimed=1 pdt=5h  MATSHITA  DVD/CDRW UJDA775  CB03


       To aid scripts that call sdparm, the exit status is set to indicate success (0) or failure
       (1 or more). Note that some of the lower values correspond to the SCSI sense  key  values.
       The exit status values are:

       0      success

       1      syntax  error. Either illegal command line options, options with bad arguments or a
              combination of options that is not permitted.

       2      the DEVICE reports that it is not ready for the operation requested. The device may
              be  in  the  process  of becoming ready (e.g.  spinning up but not at speed) so the
              utility may work after a wait.

       3      the DEVICE reports a medium or hardware error (or a blank check).  For  example  an
              attempt to read a corrupted block on a disk will yield this value.

       5      the  DEVICE  reports  an "illegal request" with an additional sense code other than
              "invalid operation code". This is often  a  supported  command  with  a  field  set
              requesting  an unsupported capability. For commands that require a "service action"
              field this value can indicate that the command is not supported.

       6      the DEVICE reports a  "unit  attention"  condition.  This  usually  indicates  that
              something  unrelated  to  the  requested command has occurred (e.g. a device reset)
              potentially before the current SCSI command was sent. The requested command has not
              been  executed  by the device. Note that unit attention conditions are usually only
              reported once by a device.

       7      the DEVICE reports a "data protect" sense key.  This  implies  some  mechanism  has
              blocked writes (or possibly all access to the media).

       9      the  DEVICE  reports  an  illegal request with an additional sense code of "invalid
              operation code" which means that it doesn't support the requested command.

       10     the DEVICE reports a "copy aborted". This implies another command or device problem
              has stopped a copy operation. The EXTENDED COPY family of commands (including WRITE
              USING TOKEN) may return this sense key.

       11     the DEVICE reports an aborted command.  In  some  cases  aborted  commands  can  be
              retried immediately (e.g. if the transport aborted the command due to congestion).

       14     the  DEVICE  reports  a miscompare sense key. VERIFY and COMPARE AND WRITE commands
              may report this.

       15     the utility is unable to open, close or use the given DEVICE.  The given file  name
              could  be  incorrect  or there may be permission problems. Adding the -v option may
              give more information.

       20     the DEVICE reports it has a check condition but "no sense".  Some polling  commands
              (e.g. REQUEST SENSE) can react this way.  It is unlikely that this value will occur
              as an exit status.

       21     the DEVICE reports a "recovered error". The requested command was successful.  Most
              likely  a  utility  will  report a recovered error to stderr and continue, probably
              leaving the utility with an exit status of 0 .

       22     the DEVICE reports that the current command or its parameters imply a logical block
              address (LBA) that is out of range.

       24     the  DEVICE  reports  a SCSI status of "reservation conflict". This means access to
              the DEVICE with the current command has been blocked because another  machine  (HBA
              or  SCSI  "initiator")  holds  a reservation on this DEVICE. On modern SCSI systems
              this is related to the use of the PERSISTENT RESERVATION family of commands.

       25     the DEVICE reports a SCSI status of "condition met". Currently only  the  PRE-FETCH
              command (see SBC-4) yields this status.

       26     the  DEVICE  reports  a  SCSI  status  of  "busy". SAM-5 defines this status as the
              logical unit is temporarily unable to process a  command.   It  is  recommended  to
              re-issue the command.

       27     the DEVICE reports a SCSI status of "task set full".

       28     the  DEVICE  reports  a  SCSI  status  of  "ACA  active".  ACA  is "auto contingent
              allegiance" and is seldom used.

       29     the DEVICE reports a SCSI status of "task aborted". SAM-5 says: "This status  shall
              be  returned  if  a  command is aborted by a command or task management function on
              another I_T nexus and the Control mode page TAS bit is set to one".

       33     the command sent to DEVICE has timed out. This occurs in Linux only; in other ports
              a command timeout will appear as a transport (or OS) error.

       40     the  command  sent  to  DEVICE  has received an "aborted command" sense key with an
              additional sense code of 0x10. This value is related to  problems  with  protection
              information (PI or DIF). For example this error may occur when reading a block on a
              drive that has never been written (or is unmapped) if that drive was formatted with
              type 1, 2 or 3 protection.

       48     this  is an internal message indicating a NVMe status field (SF) is other than zero
              after a command has been executed (i.e. something went wrong).  Work in  this  area
              is currently experimental.

       49     low level driver reports a response's residual count (i.e. number of bytes actually
              received by HBA is 'requested_bytes - residual_count') that  is  too  high.  So  no
              useful processing can be done with that response.

       50 + <os_error_number>
              OS system calls that fail often return a small integer number to help indicate what
              the error is. For example in Unix the inability of a system call to allocate memory
              returns  (in  'errno')  ENOMEM which often is associated with the integer 12. So 62
              (i.e. '50 + 12') may be returned by a utility in this case.

       97     the response to a SCSI command failed sanity checks.

       98     the DEVICE reports it has a check condition but the error doesn't fit into  any  of
              the above categories.

       99     any errors that can't be categorized into values 1 to 98 may yield this value. This
              includes transport and operating system errors after the command has been  sent  to
              the device.

       126    the utility was found but could not be executed. That might occur if the executable
              does not have execute permissions.

       127    This is the exit status for utility not found. That might occur when a script calls
              a  utility  in this package but the PATH environment variable has not been properly
              set up, so the script cannot find the executable.

       128 + <signum>
              If a signal kills a utility then the exit status is 128 plus the signal number. For
              example  if  a  segmentation  fault  occurs  then  a utility is typically killed by
              SIGSEGV which according to 'man 7 signal' has an associated signal number of 11; so
              the exit status will be 139 .

       255    the utility tried to yield an exit status of 255 or larger. That should not happen;
              given here for completeness.

       Most of the error conditions reported above will be repeatable (an example of one that  is
       not  is  "unit attention") so the utility can be run again with the -v option (or several)
       to obtain more information.


       Written by Douglas Gilbert.


       Report bugs to <dgilbert at interlog dot com>.


       Copyright © 2005-2021 Douglas Gilbert
       This software is distributed under a FreeBSD license. There is NO warranty; not  even  for


       There is a web page discussing this package at .


       hdparm(hdparm),   sg_modes,   sg_wr_mode,   sginfo,   sg_inq,  sg_vpd(all  in  sg3_utils),
       smartmontools(, mt, eject(eject),