Provided by: sg3-utils_1.42-2ubuntu1.18.04.2_amd64 
NAME
sg_inq - issue SCSI INQUIRY command and/or decode its response
SYNOPSIS
sg_inq [--ata] [--block=0|1] [--cmddt] [--descriptors] [--export] [--extended] [--help] [--hex] [--id]
[--inhex=FN] [--len=LEN] [--maxlen=LEN] [--page=PG] [--raw] [--vendor] [--verbose] [--version] [--vpd]
DEVICE
sg_inq [-36] [-a] [-A] [-b] [--B=0|1] [-c] [-cl] [-d] [-e] [-h] [-H] [-i] [-I=FN] [-l=LEN] [-m] [-M]
[-o=OPCODE_PG] [-p=VPD_PG] [-P] [-r] [-s] [-u] [-v] [-V] [-x] [-36] [-?] DEVICE
DESCRIPTION
This utility, when DEVICE is given, sends a SCSI INQUIRY command to it 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 (now obsolete) bits
are clear.
Alternatively the --inhex=FN option can be given. In this case FN is assumed to be a file name ('-' for
stdin) containing ASCII hexadecimal representing an INQUIRY response.
This utility supports two command line syntaxes. The preferred one is shown first in the synopsis and is
described in the main OPTIONS section. A later section titled OLDER COMMAND LINE OPTIONS describes 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.
In Linux, if the DEVICE exists and the SCSI INQUIRY fails (e.g. 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/BSR INCITS 502 Revision 07 which is draft
SPC-5 revision 07, 26 November 2015). It can be found at http://www.t10.org . Obsolete and reserved items
in the standard INQUIRY response output 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 non-packet 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.
-B, --block=0|1
this option controls how the file handle to the DEVICE is opened. If this argument is 0 then the
open is non-blocking. If the argument is 1 then the open is blocking. In Unix a non-blocking open
is indicated by a O_NONBLOCK flag while a blocking open is indicated by the absence of that flag.
The default value depends on the operating system and the type of DEVICE node. For Linux
pass-throughs (i.e. the sg and bsg drivers) the default is 0.
-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.
-u, --export
prints out information obtained from the device. The output can be modified by selecting a VPD
page with PG (from --page=PG). If the device identification VPD page 0x83 is given it prints out
information in the form: "SCSI_IDENT_<assoc>_<type>=<ident>" to stdout. If the device serial
number VPD page 0x80 is given it prints out information in the form: "SCSI_SERIAL=<ident>". Other
VPD pages are not supported. If no VPD page is given it prints out information in the form:
"SCSI_VENDOR=<vendor>", "SCSI_MODEL=<model>", and "SCSI_REVISION=<rev>", taken from the standard
inquiry. This may be useful for tools like udev(7) in Linux.
-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 outputs 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.
To generate output suitable for placing in a file that can be used by a later invocation with the
--inhex=FN option, use the '-HHHH' option (e.g. 'sg_inq -p di -HHHH /dev/sg3 > dev_id.hex').
-i, --id
prints the device identification VPD page [0x83].
-I, --inhex=FN
FN is expected to be a file name (or '-' for stdin) which contains ASCII hexadecimal or binary
representing an INQUIRY (including VPD page) response. This utility will then decode that
response. It is preferable to also supply the --page=PG option, if not this utility will attempt
to guess which VPD page (or standard INQUIRY) the response is associated with. The hexadecimal
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 also given then FN is treated as binary.
-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).
If PG is a negative number, then a standard INQUIRY is performed. This can be used to override
some guessing logic associated with the --inhex=FN option.
-r, --raw
in the absence of --inhex=FN then output response 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.
if used with --inhex=FN then the contents of FN is treated as binary.
-s, --vendor
output a standard INQUIRY response's vendor specific field from offset 36 to 55 in ASCII. When
used twice (i.e. '-ss') also output the vendor specific field from offset 96 in ASCII. This is
only done if the data passes some simple sanity checks.
-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").
The number of bytes output by --hex and --raw is 36 bytes or the number given to --len=LEN (or
--maxlen=LEN). That number is reduced if the "resid" returned by the HBA indicates less bytes were sent
back from DEVICE.
The DEVICE is opened with a read-only flag (e.g. in Unix with the O_RDONLY flag).
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 OPTIONS section.
-a fetch the ATA Information VPD page [0x89]. Equivalent to '--page=ai' in the OPTIONS section. 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 OPTIONS section.
-b decodes the Block Limits VPD page [0xb0]. Equivalent to '--page=bl' in the OPTIONS section. This
page is defined in SBC-2 (see www.t10.org).
-B=0|1 equivalent to --block=0|1 in OPTIONS section.
-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 OPTIONS section.
-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 OPTIONS section.
-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 OPTIONS section.
-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
OPTIONS section.
-H same action as -h. Equivalent to --hex in the OPTIONS section.
-i decodes the Device Identification VPD page [0x83]. Equivalent to --id in the OPTIONS section. 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'.
-I=FN equivalent to --inhex=FN in the OPTIONS section.
-m decodes the Management network addresses VPD page [0x85]. Equivalent to '--page=mna' in the
OPTIONS section.
-M decodes the Mode page policy VPD page [0x87]. Equivalent to '--page=mpp' in the OPTIONS section.
-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 OPTIONS section.
-r outputs the response in binary to stdout. Equivalent to --raw in the OPTIONS section. 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 OPTIONS section.
-u equivalent to '--export' in the OPTIONS section.
-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 OPTIONS
section.
-? output usage message and exit. Ignore all other parameters.
EXAMPLES
The examples in this page use Linux device names. For suitable device names in other supported Operating
Systems see the sg3_utils(8) man page.
To view the standard inquiry response use without options:
sg_inq /dev/sda
Some SCSI devices include version descriptors indicating the various SCSI standards and drafts they
support. They can be viewed with:
sg_inq -d /dev/sda
Modern SCSI devices include Vital Product Data (VPD)pages which can be viewed with the SCSI INQUIRY
command. To list the supported VPD pages (but not their contents) try:
sg_inq -e /dev/sda
Some VPD pages can be read with the sg_inq utility but a newer utility called sg_vpd specializes in
showing their contents. The sdparm utility can also be used to show the contents of VPD pages.
Further examples of sg_inq together with some typical output can be found on
http://sg.danny.cz/sg/sg3_utils.html web page.
AUTHOR
Written by Douglas Gilbert
REPORTING BUGS
Report bugs to <dgilbert at interlog dot com>.
COPYRIGHT
Copyright © 2001-2016 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)