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NAME

       sg_inq  -  sends a SCSI INQUIRY or ATA IDENTIFY (PACKET) DEVICE command
       and outputs the response

SYNOPSIS

       sg_inq [--ata] [--cmddt] [--descriptors] [--extended] [--help]  [--hex]
       [--id]   [--len=LEN]  [--maxlen=LEN]  [--page=PG]  [--raw]  [--verbose]
       [--version] [--vpd] DEVICE

       sg_inq [-36] [-a] [-A]  [-b]  [-c]  [-cl]  [-d]  [-e]  [-h]  [-H]  [-i]
       [-l=LEN]  [-m] [-M] [-o=OPCODE_PG] [-p=VPD_PG] [-P] [-r] [-s] [-v] [-V]
       [-x] [-36] [-?] DEVICE

DESCRIPTION

       This utility by default sends a  SCSI  INQUIRY  command  to  the  given
       device  and  then  outputs  the response. All SCSI devices are meant to
       respond to a "standard"  INQUIRY  command  with  at  least  a  36  byte
       response  (in  SCSI  2  and higher). An INQUIRY is termed as "standard"
       when both the EVPD and CmdDt (obsolete) bits are clear.

       This utility supports two command line syntaxes, the preferred  one  is
       shown  first  in  the  synopsis  and explained in this section. A later
       section on the old command line syntax outlines  the  second  group  of
       options.

       An  important  "non-standard" INQUIRY page is the Device Identification
       Vital Product Data (VPD) page [0x83]. Since  SPC-3,  support  for  this
       page  is  mandatory.  The  --id  option decodes this page. New VPD page
       information  is  no  longer  being  added  to  this  utility.  To   get
       information  on new VPD pages see the sg_vpd(8) or sdparm(8) utilities.

       If the DEVICE exists and the SCSI  INQUIRY  fails  (because  the  SG_IO
       ioctl  is not supported) then an ATA IDENTIFY (PACKET) DEVICE is tried.
       If it succeeds then device identification strings are output. The --raw
       and  --hex  options  can be used to manipulate the output. If the --ata
       option is given then the SCSI INQUIRY is not performed and  the  DEVICE
       is assumed to be ATA (or ATAPI).

       The  reference  document used for interpreting an INQUIRY is T10/1713-D
       Revision  11  (SPC-4,  14  May  2007)  found  at  http://www.t10.org  .
       Obsolete  items  in  the  standard  INQUIRY  response  are displayed in
       brackets. The reference document for the ATA IDENTIFY  (PACKET)  DEVICE
       command is ATA8-ACS found at http://www.t13.org .

OPTIONS

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

       -a, --ata
              Assume  given DEVICE is an ATA or ATAPI device which can receive
              ATA commands from the  host  operating  system.  Skip  the  SCSI
              INQUIRY  command  and use either the ATA IDENTIFY DEVICE command
              (for nonpacket  devices)  or  the  ATA  IDENTIFY  PACKET  DEVICE
              command.  To show the response in hex, add a ’--verbose’ option.
              This option is only available in Linux.

       -c, --cmddt
              set the Command Support Data (CmdDt) bit (defaults to clear(0)).
              Used in conjunction with the --page=PG option where PG specifies
              the SCSI command opcode to query. When used twice  (e.g.  ’-cc’)
              this  utility forms a list by looping over all 256 opcodes (0 to
              255 inclusive) only outputting a line for  found  commands.  The
              CmdDt  bit  is now obsolete.  It has been replaced by the REPORT
              SUPPORTED  OPERATION  CODES  command,  see   the   sg_opcodes(8)
              utility.

       -d, --descriptors
              decodes  and  prints the version descriptors found in a standard
              INQUIRY response. There are up to 8 of them. Version descriptors
              indicate  which  versions  of standards and/or drafts the DEVICE
              complies with. The normal components of a standard  INQUIRY  are
              output  (typically  from  the  first  36  bytes of the response)
              followed by the version descriptors if any.

       -e     see entry below for --vpd.

       -E, -x, --extended
              prints the extended INQUIRY VPD page [0x86].

       -h, --help
              print out the usage message then exit. When  used  twice,  after
              the  usage  message,  there is a list of available abbreviations
              than can be given to the --page=PG option.

       -H, --hex
              rather than decode a standard INQUIRY response, a  VPD  page  or
              command  support  data; print out the response in hex to stdout.
              Error messages and warnings are typically output to stderr. When
              used  twice with the ATA Information VPD page [0x89] decodes the
              start of the response then  output  the  ATA  IDENTIFY  (PACKET)
              DEVICE  response  in  hexadecimal bytes (not 16 bit words). When
              used three times with the ATA Information VPD page [0x89] or the
              --ata  option,  this  utility  outputs the ATA IDENTIFY (PACKET)
              DEVICE response in  hexadecimal  words  suitable  for  input  to
              ’hdparm --Istdin’.  See note below.

       -i, --id
              prints the device identification VPD page [0x83].

       -l, --len=LEN
              the  number  LEN is the "allocation length" field in the INQUIRY
              cdb.  This is the (maximum) length of the response to be sent by
              the  device.  The default value of LEN is 0 which is interpreted
              as: first request is for  36  bytes  and  if  necessary  execute
              another INQUIRY if the "additional length" field in the response
              indicates that more than 36  bytes  is  available.   If  LEN  is
              greater  than 0 then only one INQUIRY command is performed.  See
              paragraph below about "36 byte INQUIRYs".

       -m, --maxlen=LEN
              this option has the same action as the --len=LEN option. It  has
              been  added  for  compatibility  with  the  sg_vpd, sg_modes and
              sg_logs utilities.

       -O, --old
              switch to older style options.

       -p, --page=PG
              the PG argument can be either a number of an abbreviation for  a
              VPD page. To enumerate the available abbreviations for VPD pages
              use ’-hh’ or a bad abbreviation (e.g,  ’--page=xxx’).  When  the
              --cmddt  option  is  given  (once)  then PG is interpreted as an
              opcode number (so VPD page abbreviations make little sense).

       -r, --raw
              output the response in binary  to  stdout.  Error  messages  and
              warnings, if any, are sent to stderr.

       -v, --verbose
              increase level of verbosity. Can be used multiple times.

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

       -e, --vpd
              set  the  Enable  Vital  Product  Data  (EVPD)  bit (defaults to
              clear(0)). Used in conjunction with the --page=PG  option  where
              PG  specifies  the VPD page number to query. If the --page=PG is
              not given then PG defaults to zero which is the  "Supported  VPD
              pages" VPD page.

NOTES

       Some  devices  with  weak SCSI command set implementations lock up when
       they receive commands they don’t understand (or even  response  lengths
       that they don’t expect). Such devices need to be treated carefully, use
       the ’--len=36’ option. Without this option this utility will  issue  an
       initial  standard  INQUIRY requesting 36 bytes of response data. If the
       device indicates it could have supplied more data then a second INQUIRY
       is issued to fetch the longer response. That second command may lock up
       faulty devices.

       ATA or ATAPI devices that use a SCSI to ATA Translation layer (see  SAT
       at  www.t10.org) may support the ATA Information VPD page. This returns
       the IDENTIFY (PACKET) DEVICE response amongst other  things.   The  ATA
       Information VPD page can be fetched with ’--page=ai’.

       In  the INQUIRY standard response there is a ’MultiP’ flag which is set
       when the device has 2 or more ports. Some  vendors  use  the  preceding
       vendor  specific (’VS’) bit to indicate which port is being accessed by
       the INQUIRY command (0 -> relative port 1 (port  "a"),  1  ->  relative
       port 2 (port "b")). When the ’MultiP’ flag is set, the preceding vendor
       specific bit is shown in parentheses. SPC-3  compliant  devices  should
       use  the  device  identification  VPD page (0x83) to show which port is
       being used for access and the SCSI ports VPD page (0x88)  to  show  all
       available ports on the device.

       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").

ATA DEVICES

       There  are two major types of ATA devices: non-packet devices (e.g. ATA
       disks) and packet devices (ATAPI). The majority of  ATAPI  devices  are
       CD/DVD/BD drives in which the ATAPI transport carries the MMC set (i.e.
       a SCSI command  set).  Further,  both  types  of  ATA  devices  can  be
       connected  to  a  host computer via a "SCSI" (or some other) transport.
       When an ATA disk is controlled via a SCSI (or non-ATA)  transport  then
       two  approaches  are  commonly  used:  tunnelling  (e.g.  STP in Serial
       Attached SCSI (SAS)) or by emulating a SCSI device (e.g. with a SCSI to
       ATA translation layer, see SAT at www.t10.org ). Even when the physical
       transport to the host computer is ATA (especially in the case of  SATA)
       the  operating  system  may  choose  to  put  a SAT layer in the driver
       "stack" (e.g. libata in Linux).

       The main identifying command for any SCSI device  is  an  INQUIRY.  The
       corresponding  command  for an ATA non-packet device is IDENTIFY DEVICE
       while for an ATA packet device it is IDENTIFY PACKET DEVICE.

       When this utility is invoked for an  ATAPI  device  (e.g.  a  CD/DVD/BD
       drive with "sg_inq /dev/hdc") then a SCSI INQUIRY is sent to the device
       and if it responds then the response to decoded  and  output  and  this
       utility  exits.  To  see the response for an ATA IDENTIFY PACKET DEVICE
       command add the --ata option (e.g. "sg_inq --ata /dev/hdc).

       This utility doesn’t decode the response to an  ATA  IDENTIFY  (PACKET)
       DEVICE  command,  hdparm does a good job at that. The ’-HHH’ option has
       been added for use with either the ’--ata’  or  ’--page=ai’  option  to
       produce  a format acceptable to "hdparm --Istdin".  An example: ’sg_inq
       --ata -HHH /dev/hdc | hdparm --Istdin’. See hdparm.

EXIT STATUS

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

OLDER COMMAND LINE OPTIONS

       The  options  in  this  section  were  the only ones available prior to
       sg3_utils version 1.23 . In sg3_utils  version  1.23  and  later  these
       older  options can be selected by either setting the SG3_UTILS_OLD_OPTS
       environment variable or using --old (or -O) as the first option.

       -36    only  requests  36  bytes  of  response  data  for  an  INQUIRY.
              Furthermore  even if the device indicates in its response it can
              supply more data, a second (longer) INQUIRY  is  not  performed.
              This  is  a  paranoid  setting.  Equivalent to ’--len=36’ in the
              main description.

       -a     fetch  the  ATA  Information  VPD  page  [0x89].  Equivalent  to
              ’--page=ai’ in the main description. This page is defined in SAT
              (see at www.t10.org).

       -A     Assume given DEVICE is an ATA or ATAPI  device.   Equivalent  to
              --ata in the main description.

       -b     decodes  the  Block  Limits  VPD  page  [0xb0].   Equivalent  to
              ’--page=bl’ in the main description. This  page  is  defined  in
              SBC-2 (see www.t10.org).

       -c     set the Command Support Data (CmdDt) bit (defaults to clear(0)).
              Used in
               conjunction with the -o=OPCODE_PG option to  specify  the  SCSI
              command  opcode  to  query.  Equivalent  to  --cmddt in the main
              description.

       -cl    lists the command data for all supported commands  (followed  by
              the  command  name)  by  looping  through  all 256 opcodes. This
              option uses the  CmdDt  bit  which  is  now  obsolete.  See  the
              sg_opcodes(8)  utility.   Equivalent to ’--cmddt --cmddt’ in the
              main description.

       -d     decodes depending on context. If -e  option  is  given,  or  any
              option that implies -e (e.g. ’-i’ or ’-p=80’), then this utility
              attempts to  decode  the  indicated  VPD  page.   Otherwise  the
              version  descriptors  (if  any)  are listed following a standard
              INQUIRY response. In the version descriptors  sense,  equivalent
              to --descriptors in the main description.

       -e     enable  (i.e.  sets) the Vital Product Data (EVPD) bit (defaults
              to clear(0)).  Used in conjunction with the -p=VPD_PG option  to
              specify  the  VPD  page to fetch. If -p=VPD_PG is not given then
              VPD page 0 (list supported VPD pages) is assumed.

       -h     outputs INQUIRY response in hex rather than trying to decode it.
              Equivalent to --hex in the main description.

       -H     same action as -h.  Equivalent to --hex in the main description.

       -i     decodes the Device Identification VPD page [0x83]. Equivalent to
              --id  in  the  main description. This page is made up of several
              "designation descriptors". If -h is given then  each  descriptor
              header  is  decoded  and the identifier itself is output in hex.
              To see the whole VPD 0x83 page response in hex use ’-p=83 -h’.

       -m     decodes  the  Management  network  addresses  VPD  page  [0x85].
              Equivalent to ’--page=mna’ in the main description.

       -M     decodes  the  Mode  page  policy VPD page [0x87].  Equivalent to
              ’--page=mpp’ in the main description.

       -N     switch to the newer style options.

       -o=OPCODE_PG
              used in conjunction with the -e or -c option. If  neither  given
              then the -e option assumed. When the -e option is also given (or
              assumed) then the argument  to  this  option  is  the  VPD  page
              number.   The  argument  is  interpreted  as  hexadecimal and is
              expected to be in the range 0 to ff inclusive. Only VPD  page  0
              is  decoded and it lists supported VPD pages and their names (if
              known). To  decode  the  mandatory  device  identification  page
              (0x83)  use  the  -i option. A now obsolete usage is when the -c
              option is given in which case the argument  to  this  option  is
              assumed  to  be  a  command  opcode  number.  Recent  SCSI draft
              standards have moved this facility to a  separate  command  (see
              sg_opcodes(8)).  Defaults  to  0  so if -e is given without this
              option then VPD page 0 is output.

       -p=VPD_PG
              same action as -o=OPCODE_PG option  described  in  the  previous
              entry.   Since  the opcode value with the CmdDt is now obsolete,
              the main use of this option is to specify the VPD  page  number.
              The argument is interpreted as hexadecimal and is expected to be
              in the range 0 to ff inclusive.  Defaults to 0 so if -e is given
              without this option then VPD page 0 is output.

       -P     decodes  the  Unit  Path  Report  VPD  page  [0xc0] which is EMC
              specific.  Equivalent to ’--page=upr’ in the main description.

       -r     outputs the response in binary to stdout.  Equivalent  to  --raw
              in  the  main  description.   Can be used twice (i.e. ’-rr’ (and
              ’-HHH’ has same effect)) and if used with the -A  or  -a  option
              yields     output    with    the    same    format    as    "cat
              /proc/ide/hd<x>/identify" so  that  it  can  then  be  piped  to
              "hdparm --Istdin".

       -s     decodes   the   SCSI  Ports  VPD  page  [0x88].   Equivalent  to
              ’--page=sp’ in the main description.

       -v     increase level of verbosity. Can be used multiple times.

       -V     print out version string then exit.

       -x     decodes the Extended INQUIRY data VPD [0x86]  page.   Equivalent
              to ’--page=ei’ in the main description.

       -?     output usage message and exit. Ignore all other parameters.

AUTHOR

       Written by Doug Gilbert

REPORTING BUGS

       Report bugs to <dgilbert at interlog dot com>.

COPYRIGHT

       Copyright © 2001-2010 Douglas Gilbert
       This  software  is  distributed  under  the  GPL version 2. There is NO
       warranty; not even for MERCHANTABILITY  or  FITNESS  FOR  A  PARTICULAR
       PURPOSE.

SEE ALSO

       sg_opcodes(8), sg_vpd(8), sdparm(8), hdparm(8), sgdiag(scsirastools)