sg_sat_identify - send ATA IDENTIFY DEVICE command via SCSI to ATA Translation (SAT) layer
sg_sat_identify [--ck_cond] [--extend] [--help] [--hex] [--ident] [--len=CLEN] [--packet] [--raw] [--readonly] [--verbose] [--version] DEVICE
SG_SAT_IDENTIFY(8) SG3_UTILS SG_SAT_IDENTIFY(8)
NAME
sg_sat_identify - send ATA IDENTIFY DEVICE command via SCSI to ATA
Translation (SAT) layer
SYNOPSIS
sg_sat_identify [--ck_cond] [--extend] [--help] [--hex] [--ident]
[--len=CLEN] [--packet] [--raw] [--readonly] [--verbose] [--version]
DEVICE
DESCRIPTION
This utility sends either an ATA IDENTIFY DEVICE command or an ATA
IDENTIFY PACKET DEVICE command to DEVICE and outputs the response. The
devices that respond to these commands are ATA disks and ATAPI devices
respectively. Rather than send these commands directly to the device
they are sent via a SCSI transport which is assumed to contain a SCSI
to ATA Translation (SAT) Layer (SATL). The SATL may be in an operating
system driver, in host bus adapter firmware or in some external enclo-
sure.
The SAT standard (SAT ANSI INCITS 431-2007, prior draft: sat-r09.pdf at
www.t10.org) defines two SCSI "ATA PASS-THROUGH" commands: one using a
16 byte "cdb" and the other with a 12 byte cdb. This utility defaults
to using the 16 byte cdb variant. SAT-4 revision 5 added a SCSI "ATA
PASS-THROUGH(32)" command. SAT-2 and SAT-3 are now also standards:
SAT-2 ANSI INCITS 465-2010 and SAT-3 ANSI INCITS 517-2015 . The SAT-4
project is near standardization and the most recent draft is
sat4r06.pdf .
OPTIONS
Arguments to long options are mandatory for short options as well.
-c, --ck_cond
sets the CK_COND bit in the ATA PASS-THROUGH SCSI cdb. The
default setting is clear (i.e. 0). When set the SATL should
yield a sense buffer containing a ATA Result descriptor irre-
spective of whether the command succeeded or failed. When clear
the SATL should only yield a sense buffer containing a ATA
Result descriptor if the command failed.
-e, --extend
sets the EXTEND bit in the ATA PASS-THROUGH SCSI cdb. The
default setting is clear (i.e. 0). When set a 48 bit LBA command
is sent to the device. This option has no effect when --len=12.
-h, --help
outputs the usage message summarizing command line options then
exits. Ignores DEVICE if given.
-H, --hex
outputs the ATA IDENTIFY (PACKET) DEVICE response in hex. The
default action (i.e. without any '-H' options) is to output the
response in hex, grouped in 16 bit words (i.e. the ATA stan-
dard's preference). When given once, the response is output in
ASCII hex bytes (i.e. the SCSI standard's preference). When
given twice (i.e. '-HH') the output is in hex, grouped in 16 bit
words, the same as the default but without a header. When given
thrice (i.e. '-HHH') the output is in hex, grouped in 16 bit
words, in a format that is acceptable for 'hdparm --Istdin' to
process. '-HHHH' simply outputs hex data bytes, space separated,
16 per line.
-i, --ident
outputs the World Wide Name (WWN) of the device. This should be
a NAA-5 64 bit number. It is output in hex prefixed with "0x".
If not available then "0x0000000000000000" is output. The equiv-
alent for a SCSI disk (i.e. its logical unit name) can be found
with "sg_vpd -ii".
-l, --len=CLEN
CLEN this is the length of the SCSI cdb used for the ATA
PASS-THROUGH command. CLEN can either be 12, 16 or 32. The
default is 16. The larger cdb sizes are needed for 48 bit LBA
addressing of ATA devices. The ATA Auxiliary and ICC registers
are only conveyed with the 32 byte cdb variant.
-p, --packet
send an ATA IDENTIFY PACKET DEVICE command (via the SATL). The
default action is to send an ATA IDENTIFY DEVICE command. Note
that the ATAPI specification by T13 (i.e. the PACKET interface)
is now obsolete.
-r, --raw
output the ATA IDENTIFY (PACKET) DEVICE 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.
-R, --readonly
open the DEVICE read-only (e.g. in Unix with the O_RDONLY flag).
The default is to open it read-write.
-v, --verbose
increases the level or verbosity.
-V, --version
print out version string
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+--------------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+--------------------------+
|Availability | system/storage/sg3_utils |
+---------------+--------------------------+
|Stability | Pass-through uncommitted |
+---------------+--------------------------+
NOTES
Since the response to the IDENTIFY (PACKET) DEVICE command is very
important for the correct use of an ATA(PI) device (and is typically
the first command sent), a SATL should provide an ATA Information VPD
page which contains the similar information.
The SCSI ATA PASS-THROUGH (12) command's opcode is 0xa1 and it clashes
with the MMC set's BLANK command used by cd/dvd writers. So a SATL in
front of an ATAPI device that uses MMC (i.e. has peripheral device type
5) probably should treat opcode 0xa1 as a BLANK command and send it
through to the cd/dvd drive. The ATA PASS-THROUGH (16) command's opcode
(0x85) does not clash with anything so it is a better choice.
Prior to Linux kernel 2.6.29 USB mass storage limited sense data to 18
bytes which made the --ck_cond option yield strange (truncated)
results.
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from http://sg.danny.cz/sg/p/sg3_utils-1.46.tgz.
Further information about this software can be found on the open source
community website at http://sg.danny.cz/sg/sg3_utils.html.
EXAMPLES
These examples use Linux device names and a Linux utility called
hdparm. For suitable device names in other supported Operating Systems
see the sg3_utils(8) man page.
In this example /dev/sdb is a SATA 2.5" disk connected via a USB (type
C connector) dongle that implements the UAS (USB attached SCSI) proto-
col (also known as UASP). UAS is a vast improvement over the USB mass
storage class.
# sg_sat_identify /dev/sdb
Response for IDENTIFY DEVICE ATA command:
00 0c5a 3fff c837 0010 0000 0000 003f 0000 .Z ?. .7 .. .. .. .? ..
....
The hexadecimal ASCII (with plain ASCII to the right) output is
abridged to a single line (i.e. the first 16 bytes (or 8 words)). Now
to decode some of that ATA Identify response. First sg_inq can decode a
few strings:
# sg_sat_identify -HHHH /dev/sdb | sg_inq --ata -I -
ATA device: model, serial number and firmware revision:
ST9500420AS 5VJCE6R7 0002SDM1
For a lot more details, the hdparm utility is a good choice:
# sg_sat_identify -HHH /dev/sdb | hdparm --Istdin
ATA device, with non-removable media
Model Number: ST9500420AS
Serial Number: 5VJCE6R7
Firmware Revision: 0002SDM1
Transport: Serial
Standards:
....
There are about 80 more lines of details decoded by hdparm in this
case. Notice the difference in the number of "H" options: three give
an unadorned hex output arranged in (little endian) words (i.e. 16 bits
each) while four "H" options give an unadorned hex output in bytes
(i.e. 8 bits each).
EXIT STATUS
The exit status of sg_sat_identify is 0 when it is successful. Other-
wise see the sg3_utils(8) man page.
AUTHOR
Written by Douglas Gilbert
REPORTING BUGS
Report bugs to <dgilbert at interlog dot com>.
COPYRIGHT
Copyright (C) 2006-2020 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-
POSE.
SEE ALSO
sg_vpd(sg3_utils), sg_inq(sg3_utils), sdparm(sdparm), hdparm(hdparm)
sg3_utils-1.45 January 2020 SG_SAT_IDENTIFY(8)