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Updated: July 2017

sg_vpd (1m)


sg_vpd - fetches Vital Product Data (VPD) pages using a SCSI INQUIRY command


sg_vpd [--enumerate] [--help] [--hex] [--ident] [--long] [--maxlen=LEN]
[--page=PG] [--quiet] [--raw] [--verbose] [--version] DEVICE


SG_VPD(8)                          SG3_UTILS                         SG_VPD(8)

       sg_vpd  -  fetches  Vital Product Data (VPD) pages using a SCSI INQUIRY

       sg_vpd [--enumerate] [--help] [--hex] [--ident] [--long] [--maxlen=LEN]
       [--page=PG] [--quiet] [--raw] [--verbose] [--version] DEVICE

       This  utility  fetches a Vital Product Data page and decodes it or out-
       puts it in ASCII hexadecimal or binary. VPD pages are  fetched  with  a
       SCSI INQUIRY command.

       Probably  the most important page is the Device Identification VPD page
       (page number: 0x83). Since  SPC-3,  support  for  this  page  has  been
       flagged  as  mandatory.  This  page can be fetched by using the --ident

       When no options are given, other than a DEVICE, then the "Supported VPD
       pages" (0x0) VPD page is fetched and decoded.

       Arguments to long options are mandatory for short options as well.  The
       options are arranged in alphabetical order based  on  the  long  option

       -e, --enumerate
              list the names of the known VPD pages, first the standard pages,
              then the vendor specific pages. Each group is sorted in abbrevi-
              ation  order.  The DEVICE and other options are ignored and this
              utility exits after listing the VPD page names.

       -h, --help
              outputs the usage message summarizing command line options  then
              exits.  Ignores DEVICE if given.

       -H, --hex
              outputs the requested VPD page in ASCII hexadecimal. Can be used
              multiple times, see section on the ATA information vpd page.

       -i, --ident
              decode the device identification (0x83) VPD page. When used once
              this  option  has the same effect as '--page=di'. When use twice
              then the short form of the device identification VPD page's log-
              ical  unit designator is decoded. In the latter case this option
              has the same effect as '--quiet --page=di_lu'.

       -l, --long
              when decoding some VPD pages, give a  little  more  output.  For
              example  the  ATA  Information VPD page only shows the signature
              (in hex) and the IDENTIFY (PACKET) DEVICE  (in  hex)  when  this
              option is given.

       -m, --maxlen=LEN
              where  LEN  is  the  (maximum)  response  length in bytes. It is
              placed in the cdb's "allocation length" field. If not given  (or
              LEN  is  zero)  then 252 is used (apart from the ATA Information
              VPD page which defaults to 572) and, if the  response  indicates
              this value is insufficient, another INQUIRY command is sent with
              a larger value in the cdb's "allocation length" field.  If  this
              option  is given and LEN is greater than 0 then only one INQUIRY
              command is sent. Since many simple devices implement the INQUIRY
              command  badly  (and  do  not support VPD pages) then the safest
              value to use for LEN is 36. See the sg_inq man page for the more

       -p, --page=PG
              where  PG  is the VPD page to be decoded or output. The PG argu-
              ment can either be an abbreviation, a number or a pair  or  num-
              bers  separated  by  a  comma. The VPD page abbreviations can be
              seen by using the --enumerate option. If a number is given it is
              assumed  to  be  decimal  unless  it has a hexadecimal indicator
              which is either a leading '0x' or a trailing 'h'. If one  number
              is given then it is assumed to be a VPD page number. If two num-
              bers are given the second number indicates which vendor specific
              VPD  page  to  decode when several pages share the same VPD page
              number. If this option is not given (nor '-i',  '-l'  nor  '-V')
              then  the  "Supported  VPD  pages" (0x0) VPD page is fetched and
              decoded. If PG is '-1'  or  'sinq'  then  the  standard  INQUIRY
              response is output.

       -q, --quiet
              suppress the amount of decoding output.

       -r, --raw
              output  requested VPD page in binary. The output should be piped
              to a file or another utility  when  this  option  is  used.  The
              binary is sent to stdout, and errors are sent to stderr.

       -v, --verbose
              increases the level or verbosity.

       -V, --version
              print out version string then exit.

       This  VPD page (0x89 or 'ai') is defined by the SCSI to ATA Translation
       standard. It contains information about the SAT layer, the  "signature"
       of  the ATA device and the response to the ATA IDENTIFY (PACKET) DEVICE
       command. The latter part has 512 bytes of identity, capability and set-
       tings  data  which  the  hdparm utility is capable of decoding (so this
       utility doesn't decode it).

       To unclutter the output for this page, the signature and  the  IDENTIFY
       (PACKET)  DEVICE  response  are not output unless the --long option (or
       --hex or --raw) are given. When the --long option is given the IDENTIFY
       (PACKET)  DEVICE  response  is  output  as 256 (16 bit) words as is the
       fashion for ATA devices. To see that response as a string of bytes  use
       the  '-HH'  option.  To format the output suitable for hdparm to decode
       use either the '-HHH' or '-rr' option. For example if  'dev/sdb'  is  a
       SATA  disk  behind  a  SAT  layer then this command: 'sg_vpd -p ai -HHH
       /dev/sdb | hdparm --Istdin' should decode  the  ATA  IDENTIFY  (PACKET)
       DEVICE response.

       See attributes(5) for descriptions of the following attributes:

       |Availability   | system/storage/sg3_utils |
       |Stability      | Uncommitted              |
       Since  some  VPD  pages (e.g. the Extended INQUIRY page) depend on set-
       tings in the standard  INQUIRY  response,  then  the  standard  INQUIRY
       response  is  output  as  a  pseudo  VPD page when PG is set to '-1' or
       'sinq'. Also the decoding of some fields  (e.g.  the  Extended  INQUIRY
       page's  SPT  field) is expanded when the '--long' option is given using
       the standard INQUIRY response information (e.g. the PDT and the PROTECT

       In  the  2.4  series of Linux kernels the DEVICE must be a SCSI generic
       (sg) device. In the 2.6 series block  devices  (e.g.  disks  and  ATAPI
       DVDs) can also be specified. For example "sg_inq /dev/sda" will work in
       the 2.6 series kernels. From lk 2.6.6 other SCSI  "char"  device  names
       may be used as well (e.g. "/dev/st0m").

       The exit status of sg_vpd is 0 when it is successful. Otherwise see the
       sg3_utils(8) man page.

       The examples in this page use Linux device names. For  suitable  device
       names  in  other  supported  Operating Systems see the sg3_utils(8) man

       To see the VPD pages that a device supports, use with no  options.  The
       command line invocation is shown first followed by a typical response:

          # sg_vpd /dev/sdb
       Supported VPD pages VPD page:
         Supported VPD pages [sv]
         Unit serial number [sn]
         Device identification [di]
         Extended inquiry data [ei]
         Block limits (SBC) [bl]

       To  see  the  VPD page numbers associated with each supported page then
       add the '--long' option to the above command line. To view a  VPD  page
       either its number or abbreviation can be given to the '--page=' option.
       The page name abbreviations are shown within square brackets above.  In
       the next example the Extended inquiry data VPD page is listed:

          # sg_vpd --page=ei /dev/sdb
       extended INQUIRY data VPD page:
         WU_SUP=0 CRD_SUP=0 NV_SUP=0 V_SUP=0
         P_I_I_SUP=0 LUICLR=0 R_SUP=0 CBCS=0
         Multi I_T nexus microcode download=0
         Extended self-test completion minutes=0
         POA_SUP=0 HRA_SUP=0 VSA_SUP=0

       Further       examples       can       be       found       on      the
       http://sg.danny.cz/sg/sg3_utils.html web page.

       Written by Doug Gilbert

       Report bugs to <dgilbert at interlog dot com>.

       Copyright (C) 2006-2011 Douglas Gilbert
       This software is distributed under a FreeBSD license. There is NO  war-
       ranty;  not  even  for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR-

       sg_inq(sg3_utils), sg3_utils(sg3_utils), sdparm(sdparm), hdparm(hdparm)

       This    software    was    built    from    source     available     at
       https://java.net/projects/solaris-userland.    The  original  community
       source was downloaded from  http://sg.danny.cz/sg/p/sg3_utils-1.33.tgz

       Further information about this software can be found on the open source
       community website at http://sg.danny.cz/sg/sg3_utils.html.

sg3_utils-1.33                   October 2011                        SG_VPD(8)