sg_vpd - fetch SCSI VPD page and/or decode its response
sg_vpd [--all] [--enumerate]
[--examine] [--force] [--help] [--hex]
[--ident] [--inhex=FN] [--long] [--maxlen=LEN]
[--page=PG] [--quiet] [--raw] [--vendor=VP]
[--verbose] [--version] [DEVICE]
This utility, when DEVICE is given, fetches a Vital Product
Data (VPD) page and decodes it or outputs it in ASCII hexadecimal or binary.
VPD pages are fetched with a SCSI INQUIRY command.
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 a VPD page response. If the --raw option is
also given then binary input is assumed (rather than ASCII hexadecimal).
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
option.
The reference document used for interpreting VPD pages (and the
INQUIRY standard response) is T10/BSR INCITS 502 Revision 22 which is draft
SPC-5 revision 19, 22 April 2019. It can be found at http://www.t10.org
.
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
name.
- -a, --all
- decode all VPD pages. When used with DEVICE the pages to be decoded
are found in the "Supported VPD pages" VPD page. Pages that
cannot be decoded are displayed in hex; add the --long option to
have ASCII displayed to the right of each line of hex.
If this option is used with the --inhex=FN option then the file
FN is assumed to contain 1 or more VPD pages (in ASCII hex or
binary). Decoding continues until the file is exhausted (or an error
occurs). Sanity checks are aplied on each VPD page's length and the
ascending order of VPD page numbers (required by SPC-4) so bad data may be
detected.
If the --page=PG option is also given then no VPD page whose page
number is greater than PG (or its numeric equivalent) is
decoded.
- -e,
--enumerate
- list the names of the known VPD pages, first the standard pages (i.e.
those defined by T10), then the vendor specific pages. Each group is
sorted in abbreviation order. The DEVICE and most other options are
ignored and this utility exits after listing the VPD page names. May be
used together with --page=PG where PG is numeric. If so, it
searches for the summary lines of all VPD pages whose number matches
PG. May be used with --vendor=VP to restrict output to known
vendor specific pages for vendor/product VP.
- -E, --examine
- scan part of all of the VPD space (from 0x0 to 0xff) and output any pages
found. This option ignores the contents of VPD page 0x0 which should
contain a list of all supported VPD pages. However some vendors either
forget to list some standard pages or perhaps purposely don't list vendor
specific pages which are in the range 0xc0 to 0xff.
If the --page=PG option is not given and this option is given once
then the scan is from VPD page number 0x80 to 0xff inclusive. If the
--page=PG option is given then the scan is from 0x80 to PG
inclusive. If this option is given twice then the scan starts at VPD page
0x0.
The sdparm utility which lists mode and VPD pages also has a
--examine option will similar functionility.
- -f, --force
- As a sanity check, the normal action when fetching VPD pages other than
page 0x0 (the "Supported VPD pages" VPD page), is to first fetch
page 0x0 and only if the requested page is one of the supported pages, to
go ahead and fetch the requested page.
When this option is given, skip checking of VPD page 0x0 before accessing
the requested VPD page. The prior check of VPD page 0x0 is known to crash
certain USB devices, so use with care.
- -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.
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_vpd -p di -HHHH /dev/sg3 > dev_id.hex'). The reason '-HHHH'
is used is to flag that unadorned hexadecimal (without other text or
address offsets) is sent to stdout.
- -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 logical unit designator is
decoded. In the latter case this option has the same effect as '--quiet
--page=di_lu'.
- -I,
--inhex=FN
- FN is expected to be a file name (or '-' for stdin) which contains
ASCII hexadecimal or binary representing a VPD page (or a standard
INQUIRY) 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, --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 information.
- -p,
--page=PG
- where PG is the VPD page to be decoded or output. The PG
argument can either be an abbreviation, a number or a pair or
numbers/abbreviations 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 numbers (or abbreviations) are
given then the second one is the same as VP (see the
--vendor=VP option). 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. This option may also be used with the
--enumerate (see its description).
If PG is not found in the 'Supported VPD pages' VPD page (0x0) then
EDOM is returned. To bypass this check use the --force option.
- -q, --quiet
- suppress the amount of decoding output.
- -r, --raw
- if not used with --inhex=FN then 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.
if used with --inhex=FN then the contents of FN is treated as
binary.
- -M,
--vendor=VP
- where VP is a vendor (e.g. "sea" for Seagate) or
vendor/product acronym (e.g. "hp3par" for the 3PAR array from
HP). Many vendors have re-used the numbers at the beginning of the vendor
specific VPD page range (e.g. page 0xc0) and this option is a way of
selecting only those which are of interest. Using a VP of
"xxx" will list the available acronyms.
If this option is used with --page=PG and PG is an acronym
then this option is ignored. If PG is a number (e.g. 0xc0) then
VP is used to choose the which vendor specific page (e.g. sharing
page number 0xc0) to decode.
- -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 settings 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.
Since some VPD pages (e.g. the Extended INQUIRY page) depend on
settings 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 fields).
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 DEVICE is opened with a read-only flag (e.g. in Unix
with the O_RDONLY flag).
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
page.
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:
ACTIVATE_MICROCODE=0 SPT=0 GRD_CHK=0 APP_CHK=0 REF_CHK=0
UASK_SUP=0 GROUP_SUP=0 PRIOR_SUP=0 HEADSUP=1 ORDSUP=1 SIMPSUP=1
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
To check if any protection types are supported by a disk use the
'--long' option on the Extended inquiry data VPD page:
# sg_vpd --page=ei --long /dev/sdb
extended INQUIRY data VPD page:
ACTIVATE_MICROCODE=0
SPT=1 [protection types 1 and 2 supported]
GRD_CHK=1
....
Search for the name (and acronym) of all pages that share VPD page
number 0xb0 .
# sg_vpd --page=0xb0 --enumerate
Matching standard VPD pages:
bl 0xb0 Block limits (SBC)
oi 0xb0 OSD information
sad 0xb0 Sequential access device capabilities (SSC)
Some examples follow using the "--all" option. Send an
ASCII hexadecimal representation of all VPD pages to a file:
# sg_vpd --all -HHHH /dev/sg3 > all_vpds.hex
At some later time that file could be decoded with:
# sg_vpd --all --inhex=all_vpds.hex
To do the equivalent as the previous example but use a file
containing binary:
# sg_vpd --all --raw /dev/sg3 > all_vpds.bin
# sg_vpd --all --raw --inhex=all_vpds.bin
Notice that "--raw" must be given with the second
(--inhex) invocation to alert the utility that all_vpds.bin contains binary
as it assumes ASCII hexadecimal by default. Next we only decode T10
specified VPD pages excluding vendor specific VPD pages that start at page
number 0xc0:
# sg_vpd --all --page=0xbf --raw --inhex=all_vpds.bin
Further examples can be found on the
http://sg.danny.cz/sg/sg3_utils.html web page.
Written by Douglas Gilbert
Report bugs to <dgilbert at interlog dot com>.
Copyright © 2006-2019 Douglas Gilbert
This software is distributed under a FreeBSD license. There is NO warranty;
not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
sg_inq(sg3_utils), sg3_utils(sg3_utils), sdparm(sdparm),
hdparm(hdparm)