1lsscsi(8) LSSCSI lsscsi(8)
2
6 lsscsi - list SCSI devices (or hosts) and their attributes
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9 lsscsi [--classic] [--device] [--generic] [--help] [--hosts] [--kname]
10 [--list] [--lunhex] [--long] [--protection] [--protmode] [--scsi_id]
11 [--size] [--sysfsroot=PATH] [--transport] [--verbose] [--version]
12 [--wwn] [H:C:T:L]
13
15 Uses information in sysfs (Linux kernel series 2.6 and later) to list
16 SCSI devices (or hosts) currently attached to the system. Options can
17 be used to control the amount and form of information provided for each
18 device.
19 If a H:C:T:L argument is given then it acts as a filter and only
21 devices that match it are listed. The colons don't have to be present,
22 and '-', '*', '?' or missing arguments at the end are interpreted as
23 wildcards. The default is '*:*:*:*' which means to match everything.
24 Any filter string using '*' of '?' should be surrounded by single or
25 double quotes to stop shell expansions. If '-' is used as a wildcard
26 then the whole filter argument should be prefixed by '-- ' to tell this
27 utility there are no more options on the command line to be inter‐
28 preted. A leading '[' and trailing ']' are permitted (e.g. '[1:0:0]'
29 matches all LUNs on 1:0:0). May also be used to filter --hosts in which
30 case only the H is active and may be either a number or in the form
31 "host<n>" where <n> is a host number.
32 By default in this utility device node names (e.g. "/dev/sda" or
34 "/dev/root_disk") are obtained by noting the major and minor numbers
35 for the listed device obtained from sysfs (e.g. the contents of
36 "/sys/block/sda/dev") and then looking for a match in the "/dev" direc‐
37 tory. This "match by major and minor" will allow devices that have been
38 given a different name by udev (for example) to be correctly reported
39 by this utility.
40 In some situations it may be useful to see the device node name that
42 Linux would produce by default, so the --kname option is provided. An
43 example of where this may be useful is kernel error logs which tend to
44 report disk error messages using the disk's default kernel name.
45
47 Arguments to long options are mandatory for short options as well. The
48 options are arranged in alphabetical order based on the long option
49 name.
50 -c, --classic
52 The output is similar to that obtained from 'cat
53 /proc/scsi/scsi'
54 -d, --device
56 After outputting the (probable) SCSI device name the device node
57 major and minor numbers are shown in brackets (e.g.
58 "/dev/sda[8:0]").
59 -g, --generic
61 Output the SCSI generic device file name. Note that if the sg
62 driver is a module it may need to be loaded otherwise '-' may
63 appear.
64 -h, --help
66 Output the usage message and exit.
67 -H, --hosts
69 List the SCSI hosts currently attached to the system. If this
70 option is not given then SCSI devices are listed.
71 -k, --kname
73 Use Linux default algorithm for naming devices (e.g. block major
74 8, minor 0 is "/dev/sda") rather than the "match by major and
75 minor" in the "/dev" directory as discussed above.
76 -L, --list
78 Output additional information in <attribute_name>=<value> pairs,
79 one pair per line preceded by two spaces. This option has the
80 same effect as '-lll'.
81 -l, --long
83 Output additional information for each SCSI device (host). Can
84 be used multiple times for more output in which case the shorter
85 option form is more convenient (e.g. '-lll'). When used three
86 times (i.e. '-lll') outputs SCSI device (host) attributes one
87 per line; preceded by two spaces; in the form
88 "<attribute_name>=<value>".
89 -x, --lunhex
91 when this option is used once the LUN in the tuple (at the start
92 of each device line) is shown in "T10" format which is up to 16
93 hexadecimal digits. It is prefixed by "0x" to distinguish the
94 LUN from the decimal value shown in the absence of this option.
95 Also hierarchal LUNs are shown with a "_" character separating
96 the levels. For example the two level LUN: 0x0355006600000000
97 will appear as 0x0355_0066. If this option is given twice (e.g.
98 using the short form: '-xx') then the full 16 hexadecimal digits
99 are shown for each LUN, prefixed by "0x".
100 -p, --protection
102 Output target (DIF) and initiator (DIX) protection types.
103 -P, --protmode
105 Output effective protection information mode for each disk
106 device.
107 -i, --scsi_id
109 outputs the udev derived matching id found in
110 /dev/disk/by-id/scsi* . This is only for disk (and disk like)
111 devices. If no match is found then "dm-uuid-mpath*" and "usb*"
112 are searched in the same directory. If there is still no match
113 then the /sys/class/block/<disk>/holders directory is searched.
114 The matching id is printed following the device name (e.g.
115 /dev/sdc) and if there is no match "-" is output.
116 -s, --size
118 Print disk capacity in human readable form.
119 -t, --transport
121 Output transport information. This will be a target related
122 information or, if --hosts is given, initiator related informa‐
123 tion. When used without --list, a name or identifier (or both)
124 are output on a single line, usually prefixed by the type of
125 transport. For devices this information replaces the normal ven‐
126 dor, product and revision strings. When the --list option is
127 also given then additionally multiple lines of
128 attribute_name=value pairs are output, each indented by two spa‐
129 ces. See the section on transports below.
130 -v, --verbose
132 outputs directory names where information is found. Use multiple
133 times for more output.
134 -V, --version
136 outputs version information then exits.
137 -w, --wwn
139 outputs the WWN for disks instead of manufacturer, model and
140 revision (or instead of transport information). The World Wide
141 Name (WWN) is typically 64 bits long (16 hex digits) but could
142 be up to 128 bits long. To indicate the WWN is hexadecimal, it
143 is prefixed by "0x".
144 -y, --sysfsroot=PATH
146 assumes sysfs is mounted at PATH instead of the default '/sys' .
147 If this option is given PATH should be an absolute path (i.e.
148 start with '/').
149
151 This utility lists SCSI devices which are known as logical units (LU)
152 in the SCSI Architecture Model (ref: SAM-4 at http://www.t10.org) or
153 hosts when the --hosts option is given. A host is called an initiator
154 in SAM-4. A SCSI command travels out via an initiator, across some
155 transport to a target and then onwards to a logical unit. A target
156 device may contain several logical units. A target device has one or
157 more ports that can be viewed as transport end points. Each FC and SAS
158 disk is a single target that has two ports and contains one logical
159 unit. If both target ports on a FC or SAS disk are connected and visi‐
160 ble to a machine, then lsscsi will show two entries. Initiators (i.e.
161 hosts) also have one or more ports and some HBAs in Linux have a host
162 entry per initiator port while others have a host entry per initiator
163 device.
164 When the --transport option is given for devices (i.e. --hosts not
166 given) then most of the information produced by lsscsi is associated
167 with the target, or more precisely: the target port, through which SCSI
168 commands pass that access a logical unit.
169 Typically this utility provides one line of output per "device" or
171 host. Significantly more information can be obtained by adding the
172 --list option. When used together with the --transport option, after
173 the summary line, multiple lines of transport specific information in
174 the form "<attribute_name>=<value>" are output, each indented by two
175 spaces. Using a filter argument will reduce the volume of output if a
176 lot of devices or hosts are present.
177 The transports that are currently recognized are: IEEE 1394, ATA, FC,
179 iSCSI, SAS, SATA, SPI and USB.
180 For IEEE 1394 (a.k.a. Firewire and "SBP" when storage is involved), the
182 EUI-64 based target port name is output when --transport is given, in
183 the absence of the --hosts option. When the --hosts option is given
184 then the EUI-64 initiator port name is output. Output on the summary
185 line specific to the IEEE 1394 transport is prefixed by "sbp:".
186 to detect ATA and SATA a crude check is performed on the driver name
188 (after the checks for other transports are exhausted). Based on the
189 driver name either ATA or SATA transport type is chosen. Output on the
190 summary line is either "ata:" or "sata:". No other attributes are
191 given. Most device and hosts flagged as "ata:" will use the parallel
192 ATA transport (PATA).
193 For Fibre Channel (FC) the port name and port identifier are output
195 when --transport is given. In the absence of the --hosts option these
196 ids will be for the target port associated with the device (logical
197 unit) being listed. When the --hosts option is given then the ids are
198 for the initiator port used by the host. Output on the summary line
199 specific to the FC transport is prefixed by "fc:". If FCoE (over Eth‐
200 ernet) is detected the prefix is changed to "fcoe:".
201 For iSCSI the target port name is output when --transport is given, in
203 the absence of the --hosts option. This is made up of the iSCSI name
204 and the target portal group tag. Since the iSCSI name starts with "iqn"
205 no further prefix is used. When the --hosts option is given then only
206 "iscsi:" is output on the summary line.
207 For Serial Attached SCSI the SAS address of the target port (or initia‐
209 tor port if --hosts option is also given) is output. This will be a
210 naa-5 address. For SAS HBAs and SAS targets (such as SAS disks and tape
211 drives) the SAS address will be world wide unique. For SATA disks
212 attached to a SAS expander, the expander provides the SAS address by
213 adding a non zero value to its (i.e. the expander's) SAS address (e.g.
214 expander_sas_address + phy_id + 1). SATA disks directly attached to SAS
215 HBAs seem to have an indeterminate SAS address. Output on the summary
216 line specific to the SAS transport is prefixed by "sas:".
217 For the SCSI Parallel Interface (SPI) the target port identifier (usu‐
219 ally a number between 0 and 15 inclusive) is output when --transport is
220 given, in the absence of the --hosts option. When the --hosts option is
221 given then only "spi:" is output on the summary line.
222 When a USB transport is detected, the summary line will contain "usb:"
224 followed by a USB device name. The USB device name has the form
225 "<b>-<p1>[.<p2>[.<p3>]]:<c>.<i>" where <b> is the USB bus number, <p1>
226 is the port on the host. <p2> is a port on a host connected hub, if
227 present. If needed <p3> is a USB hub port closer to the USB storage
228 device. <c> refers to the configuration number while <i> is the inter‐
229 face number. There is a separate SCSI host for each USB (SCSI) target.
230 A USB SCSI target may contain multiple logical units. Thus the same
231 "usb: <device_name>" string appears for a USB SCSI host and all logical
232 units that belong to the USB SCSI target associated with that USB SCSI
233 host.
234
236 For historical reasons and as used by several other Unix based Operat‐
237 ing Systems, Linux uses a tuple of integers to describe (a path to) a
238 SCSI device (also know as a Logical Unit (LU)). The last element of
239 that tuple is the so-called Logical Unit Number (LUN). And originally
240 in SCSI a LUN was an integer, at first 3 bits long, then 8 then 16
241 bits. SCSI LUNs today (SAM-5 section 4.7) are 64 bits but SCSI stan‐
242 dards now consider a LUN to be an array of 8 bytes.
243 Up until 2013, Linux mapped SCSI LUNs to a 32 bit integer by taking the
245 first 4 bytes of the SCSI LUN and ignoring the last 4 bytes. Linux
246 treated the first two bytes of the SCSI LUN as a unit (a word) and it
247 became the least significant 16 bits in the Linux LUN integer. The next
248 two bytes of the SCSI LUN became the upper 16 bits in the Linux LUN
249 integer. The rationale for this was to keep commonly used LUNs small
250 Linux LUN integers. The most common LUN (by far) in SCSI LUN (hex)
251 notation is 00 00 00 00 00 00 00 00 and this becomes the Linux LUN
252 integer 0. The next most common LUN is 00 01 00 00 00 00 00 00 and this
253 becomes the Linux LUN integer 1.
254 In 2013 it is proposed to increase Linux LUNs to a 64 bit integer by
256 extending the mapping outlined above. In this case all information that
257 is possible to represent in a SCSI LUN is mapped a Linux LUN (64 bit)
258 integer. And the mapping can be reversed without losing information.
259 This version of the utility supports both 32 and 64 bit Linux LUN inte‐
261 gers. By default the LUN shown at the end of the tuple commencing each
262 line is a Linux LUN as a decimal integer. When the --lunhex option is
263 given then the LUN is in SCSI LUN format with the 8 bytes run together,
264 with the output in hexadecimal and prefixed by '0x'. The LUN is decoded
265 according to SAM-5's description and trailing zeros (i.e. digits to the
266 right) are not shown. So LUN 0 (i.e. 00 00 00 00 00 00 00 00) is shown
267 as 0x0000 and LUN 65 (i.e. 00 41 00 00 00 00 00 00) is shown as 0x0041.
268 If the --lunhex option is given twice then the full 64 bits (i.e. 16
269 hexadecimal digits) are shown.
270 If the --lunhex option is not given on the command line then the envi‐
272 ronment variable LSSCSI_LUNHEX_OPT is checked. If LSSCSI_LUNHEX_OPT is
273 present then its associated value becomes the number of times the
274 --lunhex is set internally. So, for example, 'LSSCSI_LUNHEX_OPT=2 lss‐
275 csi' and 'lsscsi -xx' are equivalent.
276
278 Information about this utility including examples can also be found at:
279 http://sg.danny.cz/scsi/lsscsi.html .
280
282 Information for this command is derived from the sysfs file system,
283 which is assumed to be mounted at /sys unless specified otherwise by
284 the user. SCSI (pseudo) devices that have been detected by the SCSI
285 mid level will be listed even if the required upper level drivers (i.e.
286 sd, sr, st, osst or ch) have not been loaded. If the appropriate upper
287 level driver has not been loaded then the device file name will appear
288 as '-' rather than something like '/dev/st0'. Note that some devices
289 (e.g. scanners and medium changers) do not have a primary upper level
290 driver and can only be accessed via a SCSI generic (sg) device name.
291 Generic SCSI devices can also be accessed via the bsg driver in Linux.
293 By default, the bsg driver's device node names are of the form
294 '/dev/bsg/H:C:T:L'. So, for example, the SCSI device shown by this
295 utility on a line starting with the tuple '6:0:1:2' could be accessed
296 via the bsg driver with the '/dev/bsg/6:0:1:2' device node name.
297 lsscsi version 0.21 or later is required to correctly display SCSI
299 devices in Linux kernel 2.6.26 (and possibly later) when the CON‐
300 FIG_SYSFS_DEPRECATED_V2 kernel option is not defined.
301
303 Written by Doug Gilbert
304
306 Report bugs to <dgilbert at interlog dot com>.
307
309 Copyright © 2003-2013 Douglas Gilbert
310 This software is distributed under the GPL version 2. There is NO war‐
311 ranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR‐
312 POSE.
313
315 lspci lsusb
316lsscsi-0.27 March 2013 lsscsi(8)