1SG_SAT_IDENTIFY(8) SG3_UTILS SG_SAT_IDENTIFY(8)
2
6 sg_sat_identify - send ATA IDENTIFY DEVICE command via SCSI to ATA
7 Translation (SAT) layer
8
10 sg_sat_identify [--ck_cond] [--extend] [--help] [--hex] [--ident]
11 [--len=CLEN] [--packet] [--raw] [--readonly] [--verbose] [--version]
12 DEVICE
13
15 This utility sends either an ATA IDENTIFY DEVICE command or an ATA
16 IDENTIFY PACKET DEVICE command to DEVICE and outputs the response. The
17 devices that respond to these commands are ATA disks and ATAPI devices
18 respectively. Rather than send these commands directly to the device
19 they are sent via a SCSI transport which is assumed to contain a SCSI
20 to ATA Translation (SAT) Layer (SATL). The SATL may be in an operating
21 system driver, in host bus adapter firmware or in some external enclo‐
22 sure.
23 The SAT standard (SAT ANSI INCITS 431-2007, prior draft: sat-r09.pdf at
25 www.t10.org) defines two SCSI "ATA PASS-THROUGH" commands: one using a
26 16 byte "cdb" and the other with a 12 byte cdb. This utility defaults
27 to using the 16 byte cdb variant. SAT-4 revision 5 added a SCSI "ATA
28 PASS-THROUGH(32)" command. SAT-2 and SAT-3 are now also standards:
29 SAT-2 ANSI INCITS 465-2010 and SAT3 ANSI INCITS 517-2015 . The SAT-4
30 project is near standardization and the most recent draft is
31 sat4r06.pdf .
32
34 Arguments to long options are mandatory for short options as well.
35 -c, --ck_cond
37 sets the CK_COND bit in the ATA PASS-THROUGH SCSI cdb. The
38 default setting is clear (i.e. 0). When set the SATL should
39 yield a sense buffer containing a ATA Result descriptor irre‐
40 spective of whether the command succeeded or failed. When clear
41 the SATL should only yield a sense buffer containing a ATA
42 Result descriptor if the command failed.
43 -e, --extend
45 sets the EXTEND bit in the ATA PASS-THROUGH SCSI cdb. The
46 default setting is clear (i.e. 0). When set a 48 bit LBA command
47 is sent to the device. This option has no effect when --len=12.
48 -h, --help
50 outputs the usage message summarizing command line options then
51 exits. Ignores DEVICE if given.
52 -H, --hex
54 outputs the ATA IDENTIFY (PACKET) DEVICE response in hex. The
55 default action (i.e. without any '-H' options) is to output the
56 response in hex, grouped in 16 bit words (i.e. the ATA stan‐
57 dard's preference). When given once, the response is output in
58 ASCII hex bytes (i.e. the SCSI standard's preference). When
59 given twice (i.e. '-HH') the output is in hex, grouped in 16 bit
60 words, the same as the default but without a header. When given
61 thrice (i.e. '-HHH') the output is in hex, grouped in 16 bit
62 words, in a format that is acceptable for 'hdparm --Istdin' to
63 process. '-HHHH' simply outputs hex data bytes, space separated,
64 16 per line.
65 -i, --ident
67 outputs the World Wide Name (WWN) of the device. This should be
68 a NAA-5 64 bit number. It is output in hex prefixed with "0x".
69 If not available then "0x0000000000000000" is output. The equiv‐
70 alent for a SCSI disk (i.e. its logical unit name) can be found
71 with "sg_vpd -ii".
72 -l, --len=CLEN
74 CLEN this is the length of the SCSI cdb used for the ATA
75 PASS-THROUGH command. CLEN can either be 12, 16 or 32. The
76 default is 16. The larger cdb sizes are needed for 48 bit LBA
77 addressing of ATA devices. The ATA Auxiliary and ICC registers
78 are only conveyed with the 32 byte cdb variant.
79 -p, --packet
81 send an ATA IDENTIFY PACKET DEVICE command (via the SATL). The
82 default action is to send an ATA IDENTIFY DEVICE command. Note
83 that the ATAPI specification by T13 (i.e. the PACKET interface)
84 is now obsolete.
85 -r, --raw
87 output the ATA IDENTIFY (PACKET) DEVICE response in binary. The
88 output should be piped to a file or another utility when this
89 option is used. The binary is sent to stdout, and errors are
90 sent to stderr.
91 -R, --readonly
93 open the DEVICE read-only (e.g. in Unix with the O_RDONLY flag).
94 The default is to open it read-write.
95 -v, --verbose
97 increases the level or verbosity.
98 -V, --version
100 print out version string
101
103 Since the response to the IDENTIFY (PACKET) DEVICE command is very
104 important for the correct use of an ATA(PI) device (and is typically
105 the first command sent), a SATL should provide an ATA Information VPD
106 page which contains the similar information.
107 The SCSI ATA PASS-THROUGH (12) command's opcode is 0xa1 and it clashes
109 with the MMC set's BLANK command used by cd/dvd writers. So a SATL in
110 front of an ATAPI device that uses MMC (i.e. has peripheral device type
111 5) probably should treat opcode 0xa1 as a BLANK command and send it
112 through to the cd/dvd drive. The ATA PASS-THROUGH (16) command's opcode
113 (0x85) does not clash with anything so it is a better choice.
114 Prior to Linux kernel 2.6.29 USB mass storage limited sense data to 18
116 bytes which made the --ck_cond option yield strange (truncated)
117 results.
118
120 These examples use Linux device names and a Linux utility called
121 hdparm. For suitable device names in other supported Operating Systems
122 see the sg3_utils(8) man page.
123 In this example /dev/sdb is a SATA 2.5" disk connected via a USB (type
125 C connector) dongle that implements the UAS (USB attached SCSI) proto‐
126 col (also known as UASP). UAS is a vast improvement over the USB mass
127 storage class.
128 # sg_sat_identify /dev/sdb
130 Response for IDENTIFY DEVICE ATA command:
131 00 0c5a 3fff c837 0010 0000 0000 003f 0000 .Z ?. .7 .. .. .. .? ..
132 ....
133 The hexadecimal ASCII (with plain ASCII to the right) output is
135 abridged to a single line (i.e. the first 16 bytes (or 8 words)). Now
136 to decode some of that ATA Identify response. First sg_inq can decode a
137 few strings:
138 # sg_sat_identify -HHHH /dev/sdb | sg_inq --ata -I -
140 ATA device: model, serial number and firmware revision:
141 ST9500420AS 5VJCE6R7 0002SDM1
142 For a lot more details, the hdparm utility is a good choice:
144 # sg_sat_identify -HHH /dev/sdb | hdparm --Istdin
146 ATA device, with non-removable media
147 Model Number: ST9500420AS
148 Serial Number: 5VJCE6R7
149 Firmware Revision: 0002SDM1
150 Transport: Serial
151 Standards:
152 ....
153 There are about 80 more lines of details decoded by hdparm in this
155 case. Notice the difference in the number of "H" options: three give
156 an unadorned hex output arranged in (little endian) words (i.e. 16 bits
157 each) while four "H" options give an unadorned hex output in bytes
158 (i.e. 8 bits each).
159
161 The exit status of sg_sat_identify is 0 when it is successful. Other‐
162 wise see the sg3_utils(8) man page.
163
165 Written by Douglas Gilbert
166
168 Report bugs to <dgilbert at interlog dot com>.
169
171 Copyright © 2006-2018 Douglas Gilbert
172 This software is distributed under a FreeBSD license. There is NO war‐
173 ranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR‐
174 POSE.
175
177 sg_vpd(sg3_utils), sg_inq(sg3_utils), sdparm(sdparm), hdparm(hdparm)
178sg3_utils-1.43 January 2018 SG_SAT_IDENTIFY(8)