1SG_VPD(8) SG3_UTILS SG_VPD(8)
2
6 sg_vpd - fetches Vital Product Data (VPD) pages using a SCSI INQUIRY
7 command
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10 sg_vpd [--enumerate] [--help] [--hex] [--ident] [--long] [--maxlen=LEN]
11 [--page=PG] [--quiet] [--raw] [--verbose] [--version] DEVICE
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14 This utility fetches a Vital Product Data page and decodes it or out‐
15 puts it in ASCII hexadecimal or binary. VPD pages are fetched with a
16 SCSI INQUIRY command.
17 Probably the most important page is the Device Identification VPD page
19 (page number: 0x83). Since SPC-3, support for this page has been
20 flagged as mandatory. This page can be fetched by using the --ident
21 option.
22 When no options are given, other than a DEVICE, then the "Supported VPD
24 pages" (0x0) VPD page is fetched and decoded.
25
27 Arguments to long options are mandatory for short options as well. The
28 options are arranged in alphabetical order based on the long option
29 name.
30 -e, --enumerate
32 list the names of the known VPD pages, first the standard pages,
33 then the vendor specific pages. Each group is sorted in abbrevi‐
34 ation order. The DEVICE and other options are ignored and this
35 utility exits afte listing the VPD page names.
36 -h, --help
38 outputs the usage message summarizing command line options then
39 exits. Ignores DEVICE if given.
40 -H, --hex
42 outputs the requested VPD page in ASCII hexadecimal. Can be used
43 multiple times, see section on the ATA information vpd page.
44 -i, --ident
46 decode the device identification (0x83) VPD page. When used once
47 this option has the same effect as '--page=di'. When use twice
48 then the short form of the device identification VPD page's log‐
49 ical unit designator is decoded. In the latter case this option
50 has the same effect as '--quiet --page=di_lu'.
51 -l, --long
53 when decoding some VPD pages, give a little more output. For
54 example the ATA Information VPD page only shows the signature
55 (in hex) and the IDENTIFY (PACKET) DEVICE (in hex) when this
56 option is given.
57 -m, --maxlen=LEN
59 where LEN is the (maximum) response length in bytes. It is
60 placed in the cdb's "allocation length" field. If not given (or
61 LEN is zero) then 252 is used (apart from the ATA Information
62 VPD page which defaults to 572) and, if the response indicates
63 this value is insufficient, another INQUIRY command is sent with
64 a larger value in the cdb's "allocation length" field. If this
65 option is given and LEN is greater than 0 then only one INQUIRY
66 command is sent. Since many simple devices implement the INQUIRY
67 command badly (and do not support VPD pages) then the safest
68 value to use for LEN is 36. See the sg_inq man page for the more
69 information.
70 -p, --page=PG
72 where PG is the VPD page to be decoded or output. The PG argu‐
73 ment can either be an abbreviation, a number or a pair or num‐
74 bers separated by a comma. The VPD page abbreviations can be
75 seen by using the --enumerate option. If a number is given it is
76 assumed to be decimal unless it has a hexadecimal indicator
77 which is either a leading '0x' or a trailing 'h'. If one number
78 is given then it is assumed to be a VPD page number. If two num‐
79 bers are given the second number indicates which vendor specific
80 VPD page to decode when several pages share the same VPD page
81 number. If this option is not given (nor '-i', '-l' nor '-V')
82 then the "Supported VPD pages" (0x0) VPD page is fetched and
83 decoded.
84 -q, --quiet
86 suppress the amount of decoding output.
87 -r, --raw
89 output requested VPD page in binary. The output should be piped
90 to a file or another utility when this option is used. The
91 binary is sent to stdout, and errors are sent to stderr.
92 -v, --verbose
94 increases the level or verbosity.
95 -V, --version
97 print out version string then exit.
98
100 This VPD page (0x89 or 'ai') is defined by the SCSI to ATA Translation
101 standard. It contains information about the SAT layer, the "signature"
102 of the ATA device and the response to the ATA IDENTIFY (PACKET) DEVICE
103 command. The latter part has 512 bytes of identity, capability and set‐
104 tings data which the hdparm utility is capable of decoding (so this
105 utility doesn't decode it).
106 To unclutter the output for this page, the signature and the IDENTIFY
108 (PACKET) DEVICE response are not output unless the --long option (or
109 --hex or --raw) are given. When the --long option is given the IDENTIFY
110 (PACKET) DEVICE response is output as 256 (16 bit) words as is the
111 fashion for ATA devices. To see that response as a string of bytes use
112 the '-HH' option. To format the output suitable for hdparm to decode
113 use either the '-HHH' or '-rr' option. For example if 'dev/sdb' is a
114 SATA disk behind a SAT layer then this command: 'sg_vpd -p ai -HHH
115 /dev/sdb | hdparm --Istdin' should decode the ATA IDENTIFY (PACKET)
116 DEVICE response.
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119 In the 2.4 series of Linux kernels the DEVICE must be a SCSI generic
120 (sg) device. In the 2.6 series block devices (e.g. disks and ATAPI
121 DVDs) can also be specified. For example "sg_inq /dev/sda" will work in
122 the 2.6 series kernels. From lk 2.6.6 other SCSI "char" device names
123 may be used as well (e.g. "/dev/st0m").
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126 The exit status of sg_vpd is 0 when it is successful. Otherwise see the
127 sg3_utils(8) man page.
128
130 Written by Doug Gilbert
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133 Report bugs to <dgilbert at interlog dot com>.
134
136 Copyright © 2006-2008 Douglas Gilbert
137 This software is distributed under a FreeBSD license. There is NO war‐
138 ranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR‐
139 POSE.
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142 sg_inq(sg3_utils), sdparm(sdparm), hdparm(hdparm)
143sg3_utils-1.26 February 2008 SG_VPD(8)