1SG_INQ(8) SG3_UTILS SG_INQ(8)
2
6 sg_inq - sends a SCSI INQUIRY or ATA IDENTIFY (PACKET) DEVICE command
7 and outputs the response
8
10 sg_inq [--ata] [--cmddt] [--descriptors] [--extended] [--help] [--hex]
11 [--id] [--len=LEN] [--maxlen=LEN] [--page=PG] [--raw] [--verbose]
12 [--version] [--vpd] DEVICE
13 sg_inq [-36] [-a] [-A] [-b] [-c] [-cl] [-d] [-e] [-h] [-H] [-i]
15 [-l=LEN] [-m] [-M] [-o=OPCODE_PG] [-p=VPD_PG] [-P] [-r] [-s] [-v] [-V]
16 [-x] [-36] [-?] DEVICE
17
19 This utility by default sends a SCSI INQUIRY command to the given
20 device and then outputs the response. All SCSI devices are meant to
21 respond to a "standard" INQUIRY command with at least a 36 byte
22 response (in SCSI 2 and higher). An INQUIRY is termed as "standard"
23 when both the EVPD and CmdDt (obsolete) bits are clear.
24 This utility supports two command line syntaxes, the preferred one is
26 shown first in the synopsis and explained in this section. A later sec‐
27 tion on the old command line syntax outlines the second group of
28 options.
29 An important "non-standard" INQUIRY page is the Device Identification
31 Vital Product Data (VPD) page [0x83]. Since SPC-3, support for this
32 page is mandatory. The --id option decodes this page. New VPD page
33 information is no longer being added to this utility. To get informa‐
34 tion on new VPD pages see the sg_vpd(8) or sdparm(8) utilities.
35 If the DEVICE exists and the SCSI INQUIRY fails (because the SG_IO
37 ioctl is not supported) then an ATA IDENTIFY (PACKET) DEVICE is tried.
38 If it succeeds then device identification strings are output. The --raw
39 and --hex options can be used to manipulate the output. If the --ata
40 option is given then the SCSI INQUIRY is not performed and the DEVICE
41 is assumed to be ATA (or ATAPI).
42 The reference document used for interpreting an INQUIRY is T10/1713-D
44 Revision 11 (SPC-4, 14 May 2007) found at http://www.t10.org . Obso‐
45 lete items in the standard INQUIRY response are displayed in brackets.
46 The reference document for the ATA IDENTIFY (PACKET) DEVICE command is
47 ATA8-ACS found at http://www.t13.org .
48
50 Arguments to long options are mandatory for short options as well. The
51 options are arranged in alphabetical order based on the long option
52 name.
53 -a, --ata
55 Assume given DEVICE is an ATA or ATAPI device which can receive
56 ATA commands from the host operating system. Skip the SCSI
57 INQUIRY command and use either the ATA IDENTIFY DEVICE command
58 (for nonpacket devices) or the ATA IDENTIFY PACKET DEVICE com‐
59 mand. To show the response in hex, add a '--verbose' option.
60 This option is only available in Linux.
61 -c, --cmddt
63 set the Command Support Data (CmdDt) bit (defaults to clear(0)).
64 Used in conjunction with the --page=PG option where PG specifies
65 the SCSI command opcode to query. When used twice (e.g. '-cc')
66 this utility forms a list by looping over all 256 opcodes (0 to
67 255 inclusive) only outputting a line for found commands. The
68 CmdDt bit is now obsolete. It has been replaced by the REPORT
69 SUPPORTED OPERATION CODES command, see the sg_opcodes(8) util‐
70 ity.
71 -d, --descriptors
73 decodes and prints the version descriptors found in a standard
74 INQUIRY response. There are up to 8 of them. Version descriptors
75 indicate which versions of standards and/or drafts the DEVICE
76 complies with. The normal components of a standard INQUIRY are
77 output (typically from the first 36 bytes of the response) fol‐
78 lowed by the version descriptors if any.
79 -e see entry below for --vpd.
81 -E, -x, --extended
83 prints the extended INQUIRY VPD page [0x86].
84 -h, --help
86 print out the usage message then exit. When used twice, after
87 the usage message, there is a list of available abbreviations
88 than can be given to the --page=PG option.
89 -H, --hex
91 rather than decode a standard INQUIRY response, a VPD page or
92 command support data; print out the response in hex to stdout.
93 Error messages and warnings are typically output to stderr. When
94 used twice with the ATA Information VPD page [0x89] decodes the
95 start of the response then output the ATA IDENTIFY (PACKET)
96 DEVICE response in hexadecimal bytes (not 16 bit words). When
97 used three times with the ATA Information VPD page [0x89] or the
98 --ata option, this utility outputs the ATA IDENTIFY (PACKET)
99 DEVICE response in hexadecimal words suitable for input to
100 'hdparm --Istdin'. See note below.
101 -i, --id
103 prints the device identification VPD page [0x83].
104 -l, --len=LEN
106 the number LEN is the "allocation length" field in the INQUIRY
107 cdb. This is the (maximum) length of the response to be sent by
108 the device. The default value of LEN is 0 which is interpreted
109 as: first request is for 36 bytes and if necessary execute
110 another INQUIRY if the "additional length" field in the response
111 indicates that more than 36 bytes is available. If LEN is
112 greater than 0 then only one INQUIRY command is performed. See
113 paragraph below about "36 byte INQUIRYs".
114 -m, --maxlen=LEN
116 this option has the same action as the --len=LEN option. It has
117 been added for compatibility with the sg_vpd, sg_modes and
118 sg_logs utilities.
119 -O, --old
121 switch to older style options.
122 -p, --page=PG
124 the PG argument can be either a number of an abbreviation for a
125 VPD page. To enumerate the available abbreviations for VPD pages
126 use '-hh' or a bad abbreviation (e.g, '--page=xxx'). When the
127 --cmddt option is given (once) then PG is interpreted as an
128 opcode number (so VPD page abbreviations make little sense).
129 -r, --raw
131 output the response in binary to stdout. Error messages and
132 warnings, if any, are sent to stderr.
133 -v, --verbose
135 increase level of verbosity. Can be used multiple times.
136 -V, --version
138 print out version string then exit.
139 -e, --vpd
141 set the Enable Vital Product Data (EVPD) bit (defaults to
142 clear(0)). Used in conjunction with the --page=PG option where
143 PG specifies the VPD page number to query. If the --page=PG is
144 not given then PG defaults to zero which is the "Supported VPD
145 pages" VPD page.
146
148 Some devices with weak SCSI command set implementations lock up when
149 they receive commands they don't understand (or even response lengths
150 that they don't expect). Such devices need to be treated carefully, use
151 the '--len=36' option. Without this option this utility will issue an
152 initial standard INQUIRY requesting 36 bytes of response data. If the
153 device indicates it could have supplied more data then a second INQUIRY
154 is issued to fetch the longer response. That second command may lock up
155 faulty devices.
156 ATA or ATAPI devices that use a SCSI to ATA Translation layer (see SAT
158 at www.t10.org) may support the ATA Information VPD page. This returns
159 the IDENTIFY (PACKET) DEVICE response amongst other things. The ATA
160 Information VPD page can be fetched with '--page=ai'.
161 In the INQUIRY standard response there is a 'MultiP' flag which is set
163 when the device has 2 or more ports. Some vendors use the preceding
164 vendor specific ('VS') bit to indicate which port is being accessed by
165 the INQUIRY command (0 -> relative port 1 (port "a"), 1 -> relative
166 port 2 (port "b")). When the 'MultiP' flag is set, the preceding vendor
167 specific bit is shown in parentheses. SPC-3 compliant devices should
168 use the device identification VPD page (0x83) to show which port is
169 being used for access and the SCSI ports VPD page (0x88) to show all
170 available ports on the device.
171 In the 2.4 series of Linux kernels the DEVICE must be a SCSI generic
173 (sg) device. In the 2.6 series block devices (e.g. disks and ATAPI
174 DVDs) can also be specified. For example "sg_inq /dev/sda" will work in
175 the 2.6 series kernels. From lk 2.6.6 other SCSI "char" device names
176 may be used as well (e.g. "/dev/st0m").
177
179 There are two major types of ATA devices: non-packet devices (e.g. ATA
180 disks) and packet devices (ATAPI). The majority of ATAPI devices are
181 CD/DVD/BD drives in which the ATAPI transport carries the MMC set (i.e.
182 a SCSI command set). Further, both types of ATA devices can be con‐
183 nected to a host computer via a "SCSI" (or some other) transport. When
184 an ATA disk is controlled via a SCSI (or non-ATA) transport then two
185 approaches are commonly used: tunnelling (e.g. STP in Serial Attached
186 SCSI (SAS)) or by emulating a SCSI device (e.g. with a SCSI to ATA
187 translation layer, see SAT at www.t10.org ). Even when the physical
188 transport to the host computer is ATA (especially in the case of SATA)
189 the operating system may choose to put a SAT layer in the driver
190 "stack" (e.g. libata in Linux).
191 The main identifying command for any SCSI device is an INQUIRY. The
193 corresponding command for an ATA non-packet device is IDENTIFY DEVICE
194 while for an ATA packet device it is IDENTIFY PACKET DEVICE.
195 When this utility is invoked for an ATAPI device (e.g. a CD/DVD/BD
197 drive with "sg_inq /dev/hdc") then a SCSI INQUIRY is sent to the device
198 and if it responds then the response to decoded and output and this
199 utility exits. To see the response for an ATA IDENTIFY PACKET DEVICE
200 command add the --ata option (e.g. "sg_inq --ata /dev/hdc).
201 This utility doesn't decode the response to an ATA IDENTIFY (PACKET)
203 DEVICE command, hdparm does a good job at that. The '-HHH' option has
204 been added for use with either the '--ata' or '--page=ai' option to
205 produce a format acceptable to "hdparm --Istdin". An example: 'sg_inq
206 --ata -HHH /dev/hdc | hdparm --Istdin'. See hdparm.
207
209 The exit status of sg_inq is 0 when it is successful. Otherwise see the
210 sg3_utils(8) man page.
211
213 The options in this section were the only ones available prior to
214 sg3_utils version 1.23 . In sg3_utils version 1.23 and later these
215 older options can be selected by either setting the SG3_UTILS_OLD_OPTS
216 environment variable or using --old (or -O) as the first option.
217 -36 only requests 36 bytes of response data for an INQUIRY. Further‐
219 more even if the device indicates in its response it can supply
220 more data, a second (longer) INQUIRY is not performed. This is a
221 paranoid setting. Equivalent to '--len=36' in the main descrip‐
222 tion.
223 -a fetch the ATA Information VPD page [0x89]. Equivalent to
225 '--page=ai' in the main description. This page is defined in SAT
226 (see at www.t10.org).
227 -A Assume given DEVICE is an ATA or ATAPI device. Equivalent to
229 --ata in the main description.
230 -b decodes the Block Limits VPD page [0xb0]. Equivalent to
232 '--page=bl' in the main description. This page is defined in
233 SBC-2 (see www.t10.org).
234 -c set the Command Support Data (CmdDt) bit (defaults to clear(0)).
236 Used in
237 conjunction with the -o=OPCODE_PG option to specify the SCSI
238 command opcode to query. Equivalent to --cmddt in the main
239 description.
240 -cl lists the command data for all supported commands (followed by
242 the command name) by looping through all 256 opcodes. This
243 option uses the CmdDt bit which is now obsolete. See the
244 sg_opcodes(8) utility. Equivalent to '--cmddt --cmddt' in the
245 main description.
246 -d decodes depending on context. If -e option is given, or any
248 option that implies -e (e.g. '-i' or '-p=80'), then this utility
249 attempts to decode the indicated VPD page. Otherwise the ver‐
250 sion descriptors (if any) are listed following a standard
251 INQUIRY response. In the version descriptors sense, equivalent
252 to --descriptors in the main description.
253 -e enable (i.e. sets) the Vital Product Data (EVPD) bit (defaults
255 to clear(0)). Used in conjunction with the -p=VPD_PG option to
256 specify the VPD page to fetch. If -p=VPD_PG is not given then
257 VPD page 0 (list supported VPD pages) is assumed.
258 -h outputs INQUIRY response in hex rather than trying to decode it.
260 Equivalent to --hex in the main description.
261 -H same action as -h. Equivalent to --hex in the main description.
263 -i decodes the Device Identification VPD page [0x83]. Equivalent to
265 --id in the main description. This page is made up of several
266 "designation descriptors". If -h is given then each descriptor
267 header is decoded and the identifier itself is output in hex.
268 To see the whole VPD 0x83 page response in hex use '-p=83 -h'.
269 -m decodes the Management network addresses VPD page [0x85]. Equiv‐
271 alent to '--page=mna' in the main description.
272 -M decodes the Mode page policy VPD page [0x87]. Equivalent to
274 '--page=mpp' in the main description.
275 -N switch to the newer style options.
277 -o=OPCODE_PG
279 used in conjunction with the -e or -c option. If neither given
280 then the -e option assumed. When the -e option is also given (or
281 assumed) then the argument to this option is the VPD page num‐
282 ber. The argument is interpreted as hexadecimal and is expected
283 to be in the range 0 to ff inclusive. Only VPD page 0 is decoded
284 and it lists supported VPD pages and their names (if known). To
285 decode the mandatory device identification page (0x83) use the
286 -i option. A now obsolete usage is when the -c option is given
287 in which case the argument to this option is assumed to be a
288 command opcode number. Recent SCSI draft standards have moved
289 this facility to a separate command (see sg_opcodes(8)).
290 Defaults to 0 so if -e is given without this option then VPD
291 page 0 is output.
292 -p=VPD_PG
294 same action as -o=OPCODE_PG option described in the previous
295 entry. Since the opcode value with the CmdDt is now obsolete,
296 the main use of this option is to specify the VPD page number.
297 The argument is interpreted as hexadecimal and is expected to be
298 in the range 0 to ff inclusive. Defaults to 0 so if -e is given
299 without this option then VPD page 0 is output.
300 -P decodes the Unit Path Report VPD page [0xc0] which is EMC spe‐
302 cific. Equivalent to '--page=upr' in the main description.
303 -r outputs the response in binary to stdout. Equivalent to --raw
305 in the main description. Can be used twice (i.e. '-rr' (and
306 '-HHH' has same effect)) and if used with the -A or -a option
307 yields output with the same format as "cat /proc/ide/hd<x>/iden‐
308 tify" so that it can then be piped to "hdparm --Istdin".
309 -s decodes the SCSI Ports VPD page [0x88]. Equivalent to
311 '--page=sp' in the main description.
312 -v increase level of verbosity. Can be used multiple times.
314 -V print out version string then exit.
316 -x decodes the Extended INQUIRY data VPD [0x86] page. Equivalent
318 to '--page=ei' in the main description.
319 -? output usage message and exit. Ignore all other parameters.
321
323 Written by Doug Gilbert
324
326 Report bugs to <dgilbert at interlog dot com>.
327
329 Copyright © 2001-2010 Douglas Gilbert
330 This software is distributed under the GPL version 2. There is NO war‐
331 ranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR‐
332 POSE.
333
335 sg_opcodes(8), sg_vpd(8), sdparm(8), hdparm(8), sgdiag(scsirastools)
336sg3_utils-1.29 February 2010 SG_INQ(8)