lsscsi
Table of Contents
The lsscsi command lists information about SCSI devices in
Linux. Using SCSI terminology, lsscsi lists SCSI logical
units (or SCSI targets when the '--transport' option is
given). The default action is to produce one line of output for each
SCSI device currently attached to the system. In version 0.30 of this
utility, support was added to list NVMe namespaces (under SCSI
devices(LUs)) and NVMe controllers (under SCSI hosts).
When
the '--hosts' option is given the lsscsi command lists
information about SCSI hosts attached to the system. A host can be
actual hardware (sometimes referred to as Host Bus Adapters (HBAs))
or virtual. An example of a virtual host is USB mass storage that
bridges between USB and the SCSI subsystem. In SCSI parlance, a host
is referred to as an SCSI initiator.
The lsscsi
command scans the sysfs pseudo file system that was introduced
in the 2.6 Linux kernel series. Since most users have permissions to
read sysfs (usually mounted at /sys )
then meta information can be found on some or all SCSI devices
without a user needing elevated permissions to access special files
(e.g. /dev/sda ). The lsscsi
command can also show the relationship between a device's primary
node name, its SCSI generic (sg) node name and its kernel name.
The
lsscsi command works in the 2.6, 3, 4 and 5 Linux kernel
series. At the time of writing lsscsi 0.32 was being released.
When executed without any options lsscsi outputs one line for each SCSI device attached to the system:
$lsscsi [0:0:8:0] disk FUJITSU MAM3184MP 0105 /dev/sda [2:0:0:0] cd CREATIVE CD5233E 1.00 /dev/scd0 [3:0:5:0] tape HP C5713A H910 /dev/st0 [3:0:5:1] mediumx HP C5713A H910 - [4:0:0:0] disk Linux scsi_debug 0004 /dev/sdb
The first entry on each line is the
scsi_host,channel,target_number,LUN tuple. It is placed in brackets
and each element is colon separated. When there are multiple SCSI
devices their entries are sorted in ascending tuple order. The next
column is the SCSI peripheral type; rather than using the formal name
(e.g. "direct access device") a shorter name is used. Then
follows the vendor name, the model name and the revision string. The
last entry is the primary device node name. The "primary"
device node name is associated with the upper level SCSI driver that
"owns" the device. Examples of upper level SCSI drivers are
sd (for disks), sr (for optical drives whose devices are often named
/dev/scd<n> ) and st (for tapes).
Some SCSI devices have peripheral types that either don't have upper
level drivers to control them, or the associated driver module is not
loaded. Such devices have '-' given for their device node name. All
SCSI devices can be accessed via their corresponding scsi generic
(sg) device node name (e.g. /dev/sg<n>
) which can be seen by adding a '--generic' option to the above
lsscsi invocation.
By adding the '--size' option ('-s' in
its short form) the size of disks is shown to the right of each line:
# lsscsi -s [0:0:0:0] cd/dvd PIONEER DVD-RW DVR-212D 1.22 /dev/sr0 - [1:0:0:0] disk ATA ST3320620AS 3.AA /dev/sda 320GB [6:0:0:0] disk SEAGATE ST32000444SS 0006 /dev/sdb 2.00TB
If the device is not a disk or its size is not available than '-' is output instead of a size.
Here is a "long" variant of this command. The '-l' (or '--long') option can be used multiple time for more output.
$
lscssi -l
[0:0:1:0]
disk FUJITSU MAM3184MP
0105 /dev/sda
state=running queue_depth=16
scsi_level=4 type=0 device_blocked=0 timeout=30
The
device node major and minor numbers can also be output with the '-d'
option:
$ lsscsi -d [0:0:1:0] disk FUJITSU MAM3184MP 0105 /dev/sda[8:0]
The '-g' (or '--generic') option can be used to show the corresponding scsi generic device name:
$
lsscsi -g
[0:0:1:0] disk
FUJITSU MAM3184MP
0105 /dev/sda /dev/sg0
Most modern
storage devices have world wide unique identifiers. For an ATA or
SATA disk this is known as a WWN. For a SCSI device the formal term
is an Logical Unit (LU) name which comes in several forms including
NAA and EUI-64 numbers and SCSI name strings as used by iSCSI. The
'-u (or '--unit') option will show the LU_name/WWN in place of the
manufacturer, product and revision strings:
$ lsscsi [5:0:0:0] disk FreeBSD iSCSI Disk 0123 /dev/sdb $ lsscsi -u [5:0:0:0] disk iqn.2011-03.org.example.istgt:12_ /dev/sdb The url type name used by iSCSI (called an IQN) is too large to fit where the manufacturer, product and revision strings were so it is truncated to the right with the underscore as an indication of that truncation. To see the whole IQN (and the device name to the right is dropped) use: $ lsscsi -uuu [5:0:0:0] disk iqn.2011-03.org.example.istgt:1200ssd-tgt,lun,0
In "classic" mode lsscsi outputs a listing very similar to 'cat /proc/scsi/scsi' as often used in the Linux 2.4 series. This form of output should be familiar to long term users of Linux:
$ lsscsi -c Attached devices: Host: scsi0 Channel: 00 Id: 08 Lun: 00 Vendor: FUJITSU Model: MAM3184MP Rev: 0105 Type: Direct-Access ANSI SCSI revision: 03 Host: scsi2 Channel: 00 Id: 00 Lun: 00 Vendor: CREATIVE Model: CD5233E Rev: 1.00 Type: CD-ROM ANSI SCSI revision: 02 Host: scsi3 Channel: 00 Id: 06 Lun: 00 Vendor: SONY Model: SDT-7000 Rev: 0192 Type: Sequential-Access ANSI SCSI revision: 02 Host: scsi4 Channel: 00 Id: 00 Lun: 00 Vendor: Linux Model: scsi_debug Rev: 0004 Type: Direct-Access ANSI SCSI revision: 03
SCSI host information can be listed with the '-H' option:
$ lsscsi -H [0] scsi_debug [1] aha152x $ lsscsi -Hl [0] scsi_debug cmd_per_lun=3 host_busy=0 sg_tablesize=64 unchecked_isa_dma=0 [1] aha152x cmd_per_lun=1 host_busy=0 sg_tablesize=255 unchecked_isa_dma=0 $ lsscsi -Hlv [0] scsi_debug cmd_per_lun=3 host_busy=0 sg_tablesize=64 unchecked_isa_dma=0 dir: /sys/class/scsi_host/host0 device dir: /sys/devices/pseudo_0/adapter0/host0 [1] aha152x cmd_per_lun=1 host_busy=0 sg_tablesize=255 unchecked_isa_dma=0 dir: /sys/class/scsi_host/host1 device dir: /sys/devices/platform/host1
For transport information see the section of that name below. Online
there is a "man" page (invoked by 'man lsscsi') which
contains information specific to the version of lsscsi installed on a
machine. The command also contains usage information that can be
output by using "lsscsi -h" or "lsscsi
--help".
Currently bsg device node names are not
shown by lsscsi but are quite simple to construct from the
information provided. bsg node names start with '/dev/bsg/' followed
by a scsi_host,channel,target_number,LUN tuple. For example for this
device:
[4:0:0:0] disk Linux scsi_debug 0004 /dev/sdb
the bsg node name is '/dev/bsg/4:0:0:0'. Note that the shell may interpret ":" as a special character in certain contexts so it may need to be escaped or placed between quotes.
The lsscsi command has this command line interface:
lsscsi [options] [filter]
The command line options are shown in table 1.
The filter
argument is designed to select a subset of available devices (or
hosts when the '--hosts' option is given [added version in 0.19]).
The filter can comprise of up to four numbers, separated by ":"
or spaces; alternatively it can be of the form "host<n>"
where <n> is a host number. The four numbers represent host
number, channel (or bus) number, target number and logical unit
number (i.e. LUN) respectively. The "-", "*" or
"?" symbols is used to represent a wildcard. If "-"
is used as a wild card then the filter argument should be prefixed by
"-- " in order to distinguish it from an option lead-in
character. When "*" or "?" are used as wildcard
the filter should be surrounded by single or double quotes to stop
shell filename expansions. For device listings, no filter argument is
equivalent to "-:-:-:-". Numbers missing from the filter
are treated as wildcards: hence "5:0:1" and "5:0:1:-"
are the same.
Version 0.30 of lsscsi added support for
listing NVMe devices (namespaces) and controllers. For NVMe, the four
tuple shown in lsscsi output (and used by the filter argument) is the
letter 'N' in the first position, followed by the NVMe controller's
Linux char device's minor number as seen typically in NVMe controller
device names (e.g. /dev/nvme2 (i.e.
the '2')). The third position is the value associated with the CNTLID
field in the NVMe's Admin command's Identify (controller) response.
The last item in NVMe's four tuple is the namespace identifier (nsid)
which is a value between 1 and 2**32 - 2 (inclusive).
$
lsscsi
[0:0:0:0] disk
Linux scsi_debug
0187 /dev/sda
[0:0:0:3] disk
Linux scsi_debug
0187 /dev/sdd
[1:0:0:0] disk
INTEL SS DSA2M080G2GC 2CV1 /dev/sde
[N:0:1:1] disk INTEL
SSDPEKKF256G7L__1
/dev/nvme0n1
The last two devices listed above
are SSDs. The first one is a SATA SSD (attached via USB using the UAS
protocol), the next one (last) is a NVMe SSD. The model 'number'
field (MN) of the NVMe controller containing the NVMe device (a NVMe
namespace) is output (e.g. above it's "INTEL
SSDPEKKF256G7L") followed by a double underscore and the
nsid. To see SCSI hosts and NVMe controllers use the '--hosts'
option:
$
lsscsi -H
[0] scsi_debug
[1] uas
[N:0] /dev/nvme0 INTEL SSDPEKKF256G7L
BTPY72320AU0000D 123P
In
the case of the SCSI hosts, the name of the driver controlling the
HBA is given. For NVMe controllers the Linux "char" device
name (e.g. /dev/nvme0
) is shown. This device name
is used for NVMe command injection (Admin, IO (NVM) and MI
(management interface) commands). To exclude NVMe devices
(namespaces) and controllers from the above listings, the '-N' option
can be used. Conversely to exclude SCSI devices (LUs) and hosts the
'N' filter can be given. For example:
$
lsscsi --hosts N
[N:0] /dev/nvme0 INTEL
SSDPEKKF256G7L
BTPY72320AU0000D 123P
The
trailing 'N' in the command is a filter that expands to 'N:*' which
matches all NVMe controllers. For NVMe controllers after the Linux
device name the Model Number (MN), Serial Number (SN) and Firmware
Revision (FR) fields are shown. These are obtained from the NVMe
Admin Identify (controller) command response (actually these were
obtained from sysfs which holds copies from the earlier device
discovery, thus avoiding lsscsi needing root permission). The 'N'
indicating NVMe is converted internally to 32,767 which shouldn't
interfere with any SCSI controller number. Further it means that all
NVMe devices and controllers will sort after SCSI devices and hosts
in the output.
Table 1. lsscsi command line options
long option format |
short option format |
version |
description |
--brief |
-b |
0.30 |
reduces single line output to tuple plus primary device name. With --pdt option inserts the PDT (device type) in hex between tuple and primary device name. |
--classic |
-c |
|
generate output similar to 'cat /proc/scsi/scsi' |
--controllers |
-C |
0.30 |
lists NVMe controllers and SCSI hosts. This is a synonym for --hosts |
--device |
-d |
|
show device node's major and minor numbers |
--generic |
-g |
|
show scsi generic device node name |
--help |
-h |
|
print usage message then exit |
--hosts |
-H |
|
rather than list SCSI devices (logical units), list SCSI hosts instead |
--kname |
-k |
0.15 |
show kernel name (as found in sysfs) instead of device node name (as found in the /dev directory) |
--list |
-L |
0.19 |
show <attribute>=<value> pairs, one per line, indented by two or more spaces. Equivalent to -lll option. |
--long |
-l |
|
show <attribute>=<value> pairs, several to a line. can be used multiple times for more output and different format. Use --list option to output one <attribute>=<value> pair per line. |
--long-unit |
-U |
0.29 |
show the un-truncated logical unit name. This may cause the "single device per line" form of output to exceed 80 columns with UUID and EUI-128 logical unit names |
--lunhex |
-x |
0.27 |
show the LUN part of the tuple as hex following T10 (SAM-5) conventions. |
--no-nvme |
-N |
0.30 |
don't list NVMe devices (or controllers if --hosts is given) |
--pdt |
-D |
0.30 |
displays Peripheral Device Type (PDT) is hexadecimal, prefixed by "0x" |
--protection |
-p |
0.22 |
show protection information (T10-DIF). |
--protmode |
-P |
0.25 |
show negotiated protection information mode |
--scsi_id |
-i |
0.27 |
show udev derived information in /dev/disk/by-id/ directory |
--size |
-s |
0.25 |
show disk size in human readable form. Used once, normal SI prefixes to 'B' (bytes or octets) are used, rounded by up to 3 decimal places. When used twice IEC 80000-3 prefixes for 'B' are used, for example MiB, GiB and TiB stand for 2^20, 2^30 and 2^40 bytes respectively. When used three times the size as a logical block count is given, this is an exact figure, in decimal. |
--sysfsroot=PATH |
-y PATH |
0.23 |
Uses PATH as sysfs mount point (default sysfs mount point is '/sys') |
--sz-lbs |
-S |
0.30 |
show disk size as number of logical blocks; when given twice adds a comma followed the logical block size in bytes (typically either 512 or 4096) |
--transport |
-t |
0.19 |
show transport information. If '--hosts' not given then this will be for targets. If '--hosts' is given then this will be for initiators (i.e. hosts). More information shown when used with '--list'. |
--unit |
-u |
0.28 |
show the LU name in the place of the manufacturer, model and revision. Needs lk >= 3.15 |
--verbose |
-v |
|
increase verbosity of output. May be used multiple times to further increase verbosity. |
--version |
-V |
|
print out the version and the date of last code change then exits |
--wwn |
-w |
0.26 |
show the WWN for disks in the place of the manufacturer, model and revision |
The lsscsi man page and the usage message in
the executable also show the command line syntax.
When the '--transport' (or '-t') option is given lsscsi attempts to determine the transport being used and outputs information specific to that transport. In the case of modern transports that may include a world wide unique name or identifier. The transports for which extra information is provided are:
ATA
Fibre channel (FC): substantial amount both for target and host
IEEE 1394 (SBP): target and host
iSCSI: target only
PCIe, as used by NVMe
Serial Attached SCSI (SAS): substantial amount for both target and host
SATA
SCSI Parallel Interface (SPI): trivial
SCSI RDMA (Remote Direct Memory Access) Protocol (SRP)
USB
Even though lsscsi, in the absence of the '--hosts' option,
shows logical unit information, once the '--transport' option is
specified the output relates to the target which
contains the logical unit. This occurs since the computer (and thus
sysfs) see a "transport" (or interconnect) whose near end
is a host (i.e. a SCSI initiator) and whose far end is a target.
A target may contain one or more logical units (and in special cases
a target may contain no logical units). SCSI initiators and targets
can also have one or more ports. Linux tends to show each port of a
target (that contains one logical unit) as two devices; to be more
precise, Linux shows a different device for each distinct path to a
logical unit.
When the '--transport' option is given the
SCSI INQUIRY strings (vendor, product and revision) usually output by
lsscsi are replaced by a target name or identifier. Annex A in
the SAM-4
document has been used as a guide for the appropriate initiator (i.e.
host) and target names and identifiers to display.
From
lsscsi version 0.28 the '--unit' option will show Logical Unit (LU)
name derived from device identification VPD page which first became
available in sysfs in lk 3.15 . For most modern SCSI devices the LU
name should be a world wide unique number (or string in the case of
iSCSI).
In version 0.30 of lsscsi support for NVMe was
added.
The detection of parallel ATA devices is somewhat crude and is performed after checks are made for more traditional SCSI transports. The identification of an ATA transport is made on the basis of the low level driver name that the device or host uses. A similar mechanism is used to detect SATA devices and there is some overlap since some drivers support both SATA and PATA devices. No other attributes are provided. For example:
$
lsscsi
[0:0:0:0]
disk ATA FUJITSU
MHY2160B 0000 /dev/sda
[3:0:0:0]
cd/dvd MATSHITA DVD/CDRW UJDA775 CB03
/dev/scd0
[5:0:0:0]
disk USB 2.0 SD/MMC Reader
/dev/sdb
[6:0:0:0]
disk JetFlash TS2GJFVxx
8.01 /dev/sdc
$
lsscsi -t
[0:0:0:0]
disk sata:
/dev/sda
[3:0:0:0]
cd/dvd ata:
/dev/scd0
[5:0:0:0]
disk usb: 7-1:1.0
/dev/sdb
[6:0:0:0]
disk usb: 7-2.4:1.0
/dev/sdc
$ lsscsi -Ht
[0] ahci
sata:
[1] ahci
sata:
[2] ahci
sata:
[3] ata_piix
ata:
[4] ata_piix
ata:
[5] usb-storage usb:
7-1:1.0
[6] usb-storage usb:
7-2.4:1.0
In
this case the device at 3:0:0:0 (and device node /dev/scd0) is a
DVD/CD drive whose transport is (parallel) ATA. That device is
attached to host3 which is associated with the ata_piix driver.
For FC devices (logical units), the '--transport' option will show the port name and the port identifier instead of the SCSI INQUIRY "strings". For example:
$
lsscsi -g
[3:0:0:0]
enclosu HP A6255A
HP04 -
/dev/sg3
[3:0:1:0]
disk HP 36.4G ST336753FC
HP00 /dev/sdd /dev/sg4
[3:0:2:0]
disk HP 36.4G ST336753FC
HP00 /dev/sde /dev/sg5
$
lsscsi -g --transport
[3:0:0:0]
enclosu fc:0x50060b00002e48a3,0x0b109b -
/dev/sg3
[3:0:1:0]
disk fc:0x21000004cf97de68,0x0b109f /dev/sdd
/dev/sg4
[3:0:2:0]
disk fc:0x21000004cf97e385,0x0b10a3 /dev/sde
/dev/sg5
Notice that the port name for the
enclosure is NAA-5 while the port names for the disks are NAA-2.
Since SAS also uses NAA-5 the leading "fc:" indicates that
the transport has been identified as FC. When '--list' is added, more
transport information is provided in "name=value" pairs,
indented by two or more spaces. The output is restricted to one disk
by added the 3:0:2:0 filter:
$ lsscsi -t --list [3:0:2:0] [3:0:2:0] disk fc:0x21000004cf97e385,0x0b10a3 /dev/sde transport=fc node_name=0x20000004cf97e385 port_name=0x21000004cf97e385 port_id=0x0b10a3 port_state=Online roles=FCP Target scsi_target_id=2 supported_classes=Class 3 dev_loss_tmo=35 When the '--hosts' option is used with '--transport' then transport information for the initiator (port) is output:
$
lsscsi --hosts --transport 3
[3]
qla2xxx
fc:0x50060b00741cc28e,0x0b1900
This shows
for host 3 the driver is called qla2xxx, the transport is FC, the
initiator's port name is in NAA-5 format with the final (hex) number
being the initiator's port identifier. Adding '--list' will again add
"name=value" pairs:
$ lsscsi -H -t --list 3 [3] qla2xxx fc:0x50060b00741cc28e,0x0b1900 transport=fc node_name=0x50060b00741cc28f port_name=0x50060b00741cc28e port_id=0x0b1900 port_type=NPort (fabric via point-to-point) speed=2 Gbit supported_classes=Class 3 tgtid_bind_type=wwpn (World Wide Port Name)
The "name=value" pairs are fetched from a sysfs directory (apart from "transport=fc") so the meaning should be what is defined by the transport. Too see which directory (or directories) provide this information add '-vvv'.
There are two versions of the SBP SCSI standard known as SBP-2 and
SBP-3 for conveying SCSI command sets over a IEEE 1394 transport. The
SCSI commands sets are typically for accessing storage devices. Hence
the acronym "SBP" is often associated with the IEEE 1394
transport in the storage context.
SBP defines world wide
unique names for a target and initiator (host) using EUI-64 format.
These names are what the lsscsi command fetches when the '-t' option
is given:
$
lsscsi
[6:0:1:0]
sim dsk QUANTUM FIREBALL SE3.2A
/dev/sdk
$
lsscsi -t
[6:0:1:0]
sim dsk sbp:00043b000000071d:1:0
/dev/sdk
$
lsscsi -t -L
[6:0:1:0]
sim dsk sbp:00043b000000071d:1:0
/dev/sdk
transport=sbp
ieee1394_id=00043b000000071d:1:0
$
lsscsi -t -H
[6]
sbp2
sbp:005042b500004a48
$
lsscsi -t -H -L
[6]
sbp2
sbp:005042b500004a48
transport=sbp
The
SBP standard requires that disks (typically ATA disks in an external
enclosure) use the SCSI peripheral device type: "simplified
direct access device". The is abbreviated by the lsscsi command
to "sim dsk".
The lsscsi command won't show anything iSCSI related on a machine with a iSCSI target running (either as a kernel driver or as a user space daemon). The following output is from a machine running a iSCSI initiator with a session established:
$ lsscsi [2:0:0:0] disk IET VIRTUAL-DISK 0 /dev/sda $ lsscsi -t [2:0:0:0] disk iqn.2001-04.com.example:sda.sdb.sdc,t,0x1 /dev/sda $ lsscsi -t -L [2:0:0:0] disk iqn.2001-04.com.example:sda.sdb.sdc,t,0x1 /dev/sda transport=iSCSI targetname=iqn.2001-04.com.example:sda.sdb.sdc tpgt=1 data_pdu_in_order=1 data_seq_in_order=1 erl=0 first_burst_len=65536 initial_r2t=1 max_burst_len=262144 max_outstanding_r2t=1 recovery_tmo=120 $ lsscsi -t -H [2] iscsi_tcp iscsi: $ lsscsi -t -H -L [2] iscsi_tcp iscsi: transport=iSCSI As can be seen, there is no useful host information (e.g. the iSCSI initiator name) when the '-H' option (or the '--hosts' option) is given. The information given for the target is session related. An iSCSI session is made up of 1 or more connections which have available information in sysfs but the lsscsi command doesn't output them currently.
It is possible that SCSI SOP/PQI devices are present but more likely the presence of a PCIe storage transport indicates one or more NVMe devices are available. In version 0.30 of lsscsi support for NVMe was added. Here is an example of the requesting transport information on a machine's SCSI hosts and NVMe controllers:
$ lsscsi -H --transport [0] ahci sata: [1] ahci sata: [2] ahci sata: [3] ahci sata: [4] ahci sata: [5] ahci sata: [6] mpt3sas sas:0x500605b006d3b510 [7] scsi_debug [N:0] /dev/nvme0 pcie 0x1b4b:0x1093
In the above, SCSI hosts 0 to 5 are actually SATA hosts,
host 6 is a LSI SAS HBA, host 7 is scsi_debug which has no transport
(actually it has a "bus" as seen from sysfs called
'pseudo'). The last item is a NVMe controller attached via a PCIe
bus. Following the "pcie" string is the Subsystem Vendor ID
(SSVID) before the colon, with the subsystem device identifier after
the colon. Now looking are the corresponding devices (SATA devices,
SCSI LUs (logical units (LUs) and NVMe namespaces):
$ lsscsi [3:0:0:0] disk ATA ST9500420AS SDM1 /dev/sda [6:0:0:0] disk SEAGATE ST10000NM0096 E002 /dev/sdb [6:0:1:0] disk SmrtStor SDLKOCDR800G5CA1 F820 /dev/sdc [6:0:2:0] disk SEAGATE ST200FM0073 0007 /dev/sdd [6:0:3:0] enclosu Areca ARC-802801.33.63 0133 - [6:0:4:0] enclosu Intel RES2SV240 0d00 - [7:0:0:0] disk Linux scsi_debug 0186 /dev/sde [N:0:0:1] disk WDC WDS256G1X0C-00ENX0__1 /dev/nvme0n1
A SATA disk can be seen at [3:0:0:0]; a SAS disk and to SAS SSDs follow, then two SES enclosures (associated with SAS expanders), then a scsi_debug device (LU) and finally a NVMe SSD at [N:0:0:1]. The namespace id is 1 and is shown two ways: the final element in the tuple and the "__1" suffix on the name. Now that list again with the --generic and --size options:
$ lsscsi -gs [3:0:0:0] disk ATA ST9500420AS SDM1 /dev/sda /dev/sg0 500GB [6:0:0:0] disk SEAGATE ST10000NM0096 E002 /dev/sdb /dev/sg1 10.0TB [6:0:1:0] disk SmrtStor SDLKOCDR800G5CA1 F820 /dev/sdc /dev/sg2 800GB [6:0:2:0] disk SEAGATE ST200FM0073 0007 /dev/sdd /dev/sg3 200GB [6:0:3:0] enclosu Areca ARC-802801.33.63 0133 - /dev/sg4 - [6:0:4:0] enclosu Intel RES2SV240 0d00 - /dev/sg5 - [7:0:0:0] disk Linux scsi_debug 0186 /dev/sde /dev/sg6 8.38MB [N:0:0:1] disk WDC WDS256G1X0C-00ENX0__1 /dev/nvme0n1 256GB
Notice there is no generic device name for the NVMe namespace. The pass-through for NVMe Admin and NVM (I/O) commands is actually through the associated controller's device (i.e. /dev/nvme0). To only see NVMe namespaces (or controllers) use the 'N' filter:
$ lsscsi -s N [N:0:0:1] disk WDC WDS256G1X0C-00ENX0__1 /dev/nvme0n1 256GB
To suppress the NVMe namespace (or controller) output use the '-N' option.
For SAS devices (logical units), the '--transport' option will show the target's SAS (port) address instead of the SCSI INQUIRY "strings". For example:
$ lsscsi -t [4:0:3:0] disk sas:0x5000d50001b02139 /dev/sdd [4:0:4:0] disk sas:0x5000d500005208ed /dev/sde [5:0:0:0] disk sas:5000d50001b02139 /dev/sdf [5:0:1:0] disk sas:5000d500005208ed /dev/sdg
The SAS address is prefixed by "sas:" to identify the transport. The are currently two different representations and lsscsi prints out whatever is in the relevant sysfs attribute. When a '--list' (or '-L) option is added more information is output:
$
lsscsi -t -L [4:0:4:0]
[4:0:4:0]
disk sas:0x5000d500005208ed
/dev/sde
transport=sas
initiator_port_protocols=none
initiator_response_timeout=10000
I_T_nexus_loss_timeout=1744
phy_identifier=11
ready_led_meaning=1
sas_address=0x5000d500005208ed
target_port_protocols=ssp
#
lsscsi -t -L [5:0:1:0]
[5:0:1:0] disk
sas:5000d500005208ed
/dev/sdg
transport=sas
sub_transport=sas_class
device_name=0000000000000000
dev_type=end device
iproto=
iresp_timeout=0x2710
itnl_timeout=0x07d0
linkrate=3,0 Gbps
max_linkrate=3,0 Gbps
max_pathways=1
min_linkrate=3,0 Gbps
pathways=1
ready_led_meaning=1
rl_wlun=0
sas_addr=5000d500005208ed
tproto=SSP
transport_layer_retries=0
Both
4:0:4:0 and 5:0:1:0 are the same logical unit accessed via the same
target port but from different hosts. The two drivers (one for each
host) choose to represent the same (target port) information in
different ways.
When the '--hosts' option is added, then
the SAS address of the initiator is output. In the case of SAS a
Linux host corresponds to a initiator device (not one of its ports):
$ ./lsscsi -t -H [0] sata_nv [1] sata_nv [2] sata_nv [3] sata_nv [4] mptsas sas:0x500605b000f6f260 [5] aic94xx sas:50000d100f2dc000
Adding a '--list' option will print multiple 'name=value' pair lines, each indented with two or more spaces.
The detection of serial ATA (SATA) devices is somewhat crude and is performed after checks are made for more traditional SCSI transports. The identification of an SATA transport is made on the basis of the low level driver name that the device or host uses. A similar mechanism is used to detect parallel ATA devices and there is some overlap since some drivers support both SATA and PATA devices. No other attributes are provided. See the example in the ATA section, specifically device 0:0:0:0 and the associated host0.
The SCSI parallel interface (SPI) can be detected and is indicated by the "spi:" prefix. Sysfs provides no world wide unique names (until lk 3.15 when it provides the device identification VPD page). The only thing that is available is the target identifier which is usually a number between 0 and 15 inclusive. The initiator (host) identifier is not provided by by convention it is usually 7. Following are some examples of target and host transport information for SPI:
$ lsscsi [0:0:1:0] [0:0:1:0] disk HP 36.4G ST336753LC HPC7 /dev/sdb $ lsscsi -t [0:0:1:0] [0:0:1:0] disk spi:1 /dev/sdb $ lsscsi -t -L [0:0:1:0] [0:0:1:0] disk spi:1 /dev/sdb transport=spi target_id=1 dt=1 max_offset=127 max_width=1 min_period=6.25 offset=63 period=6.25 width=1 $ lsscsi -t -H [0:0:1:0] [0] mptspi spi: $ lsscsi -t -H -L [0:0:1:0] [0] mptspi spi: transport=spi signalling=unknown
The SCSI RDMA Protocol (SRP) transport can be detected and is indicated by the "srp:" prefix. Support was added in lsscsi version 0.28 . Here are some examples from its contributor, Bart Van Assche:
$ ibstat | grep 'Port GUID'
Port GUID: 0x0002c90300a05281
Port GUID: 0x0002c90300a05282
Port GUID: 0x0002c90300a02d71
Port GUID: 0x0002c90300a02d72
$ lsscsi -t
[0:0:0:0] disk /dev/sda
[0:3:0:0] storage -
[1:0:0:0] disk srp:0002:c903:00a0:5281 /dev/sdb
[1:0:0:1] disk srp:0002:c903:00a0:5281 /dev/sdc
[1:0:0:2] disk srp:0002:c903:00a0:5281 /dev/sdd
[1:0:0:3] disk srp:0002:c903:00a0:5281 /dev/sde
[1:0:0:4] disk srp:0002:c903:00a0:5281 /dev/sdf
[1:0:0:5] disk srp:0002:c903:00a0:5281 /dev/sdg
[1:0:0:6] disk srp:0002:c903:00a0:5281 /dev/sdh
[1:0:0:7] disk srp:0002:c903:00a0:5281 /dev/sdi
$ lsscsi --list -t | head
[0:0:0:0] disk /dev/sda
[0:3:0:0] storage -
[1:0:0:0] disk srp:0002:c903:00a0:5281 /dev/sdb
transport=srp
orig_dgid=f452:1403:0015:6021
dgid=f452:1403:0015:6021
[1:0:0:1] disk srp:0002:c903:00a0:5281 /dev/sdc
transport=srp
orig_dgid=f452:1403:0015:6021
dgid=f452:1403:0015:6021When a USB transport is detected the device or host summary line will contain "usb:" followed by a USB device name. The USB device name has the form "<b>-<p1>[.<p2>]+:<c>.<i>" where <b> is the USB bus number, <p1> is the port on the host. <p2> is a port on a host connected hub, if present. If needed <p3> is another USB hub port closer to the USB storage device. <c> refers to the configuration number while <i> is the interface number. There is a separate USB SCSI host for each USB (SCSI) target. A USB SCSI target may contain multiple logical units. Thus the same "usb: <device_name>" string appears for a USB SCSI host and all logical units that belong to the USB SCSI target associated with that USB SCSI host. See the example in the ATA section, specifically devices 5:0:0:0 and 6:0:0:0 . 5:0:0:0 is connected directly to a laptop while 6:0:0:0 is connected via an external hub.
Here is the output from a not so typical machine. It has a directly attached SATA DVD drive and one SATA disk (/dev/sda). The remaining devices are attached via an external SAS expander which has its own SES management device [6:0:2:0] :
#
lsscsi
[0:0:0:0]
cd/dvd PIONEER DVD-RW DVR-212D 1.22 /dev/sr0
[1:0:0:0]
disk ATA
ST3320620AS 3.AA /dev/sda
[6:0:0:0]
disk SEAGATE ST32000444SS
0006 /dev/sdb
[6:0:1:0]
disk ATA
ST3500418AS CC34 /dev/sdc
[6:0:2:0]
enclosu Intel RES2SV240
0600 -
[6:0:3:0]
disk SEAGATE ST373455SS
2189 /dev/sdd
Below
are some examples of filters:
#
lsscsi -- 1:-:-:-
[1:0:0:0] disk
ATA ST3320620AS
3.AA /dev/sda
# lsscsi "*:*:2"
[6:0:2:0]
enclosu Intel RES2SV240
0600 -
# lsscsi 0
[0:0:0:0]
cd/dvd PIONEER DVD-RW DVR-212D 1.22
/dev/sr0
# lsscsi 2
#
# lsscsi
6
[6:0:0:0] disk SEAGATE
ST32000444SS 0006 /dev/sdb
[6:0:1:0] disk ATA
ST3500418AS CC34 /dev/sdc
[6:0:2:0] enclosu Intel
RES2SV240 0600
-
[6:0:3:0]
disk SEAGATE ST373455SS
2189 /dev/sdd
NVMe
namespaces have 'N' in place of the first item in the h:c:t:l tuple.
For NVMe controllers [N, <controller_device_minor_number>] is
output.
# lsscsi [3:0:0:0] disk SEAGATE ST10000NM0096 E002 /dev/sdb [3:0:1:0] disk SmrtStor SDLKOCDR800G5CA1 F820 /dev/sdc [3:0:2:0] disk SEAGATE ST200FM0073 0007 /dev/sdd [3:0:3:0] enclosu Areca ARC-802801.33.63 0133 - [3:0:4:0] enclosu Intel RES2SV240 0d00 - [4:0:0:0] disk ATA ST9500420AS SDM1 /dev/sda [N:0:0:1] disk WDC WDS256G1X0C-00ENX0__1 /dev/nvme0n1 # lsscsi -H [0] ahci [1] ahci [2] ahci [3] mpt3sas [4] ahci [5] ahci [6] ahci [N:0] /dev/nvme0 WDC WDS256G1X0C-00ENX0 172322800697 B35500WD # lsscsi -Ht [0] ahci sata: [1] ahci sata: [2] ahci sata: [3] mpt3sas sas:0x500605b006d3b510 [4] ahci sata: [5] ahci sata: [6] ahci sata: [N:0] /dev/nvme0 pcie 0x1b4b:0x1093
Here is another sequence of host/controller output show the --long option and the triple long (-L) option.
# lsscsi -H [0] scsi_debug [N:0] /dev/nvme0 INTEL SSDPEKKF256G7L BTPY72320AU6256D 131P # lsscsi -Hl [0] scsi_debug cmd_per_lun=255 host_busy=0 sg_tablesize=2048 unchecked_isa_dma=0 [N:0] /dev/nvme0 cntlid=1 state=live current_link_width=2 firmware_rev=131P # lsscsi -HL [0] scsi_debug can_queue=32 cmd_per_lun=255 host_busy=0 nr_hw_queues=4 sg_tablesize=2048 state=running unchecked_isa_dma=0 unique_id=0 [N:0] /dev/nvme0 cntlid=1 state=live current_link_width=2 firmware_rev=131P current_link_speed=8.0 GT/s PCIe model=INTEL SSDPEKKF256G7L serial=BTPY72320AU6256D
Now let's look at the sizes of the disks using the '--size' or '-s' option. The size of a DVD disk, even if there is one in the drive and it is mounted, is not shown. And there is no size associated with the enclosure (SES) device:
# lsscsi -s [0:0:0:0] cd/dvd PIONEER DVD-RW DVR-212D 1.22 /dev/sr0 - [1:0:0:0] disk ATA ST3320620AS 3.AA /dev/sda 320GB [6:0:0:0] disk SEAGATE ST32000444SS 0006 /dev/sdb 2.00TB [6:0:1:0] disk ATA ST3500418AS CC34 /dev/sdc 500GB [6:0:2:0] enclosu Intel RES2SV240 0600 - - [6:0:3:0] disk SEAGATE ST373455SS 2189 /dev/sdd 73.4GB So how to access that enclosure (SES) device? Use the '--generic' or '-g' option to see the corresponding SCSI generic device names: # lsscsi -g [0:0:0:0] cd/dvd PIONEER DVD-RW DVR-212D 1.22 /dev/sr0 /dev/sg0 [1:0:0:0] disk ATA ST3320620AS 3.AA /dev/sda /dev/sg1 [6:0:0:0] disk SEAGATE ST32000444SS 0006 /dev/sdb /dev/sg2 [6:0:1:0] disk ATA ST3500418AS CC34 /dev/sdc /dev/sg3 [6:0:2:0] enclosu Intel RES2SV240 0600 - /dev/sg4 [6:0:3:0] disk SEAGATE ST373455SS 2189 /dev/sdd /dev/sg5
So the enclosure device can be accessed via /dev/sg4 (e.g. with
a command like 'sg_ses /dev/sg4'). The lsscsi utility does not show
the bsg device name but it is easily constructed from the above
information; in this case it will be '/dev/bsg/6:0:2:0'. Note,
depending on the context, those ":" characters may need to
be escaped lest the shell interprets them as special
characters.
Version 0.26 adds the '--wwn' option to
display the World Wide Number of a disk (i.e. Logical Unit name in
SCSI terminology), typically in NAA-5 format. Following is lsscsi
invoked with no option, the '--wwn' option then the '--transport'
option:
#
lsscsi
[1:0:0:0] disk
ATA ST3160812AS
3.AA /dev/sda
[6:0:0:0] disk
ATA ST3500418AS
CC34 /dev/sdb
[6:0:1:0] disk
SEAGATE ST32000444SS 0006
/dev/sdc
[6:0:2:0] enclosu Intel
RES2SV240 0600 -
#
lsscsi --wwn
[1:0:0:0] disk
ATA ST3160812AS
3.AA
/dev/sda
[6:0:0:0] disk
ATA ST3500418AS
CC34 0x5000c500120bfe84
/dev/sdb
[6:0:1:0] disk
SEAGATE ST32000444SS 0006
0x5000c500215725bf
/dev/sdc
[6:0:2:0] enclosu Intel
RES2SV240
0600
-
# lsscsi
--transport
[1:0:0:0] disk
sata:
/dev/sda
[6:0:0:0] disk
sas:0x5001517e85c3efe5
/dev/sdb
[6:0:1:0] disk
sas:0x5000c500215725bd
/dev/sdc
[6:0:2:0] enclosu
sas:0x5001517e85c3effd
-
Notice that both
the '--wwn' and '--transport' options replace the manufacturer, model
and revision information. The disk at /dev/sda
is an older SATA model that doesn't have a WWN and is connected via a
SATA controller on the computer motherboard. The other two disks are
connected via a SAS expander: /dev/sdb
is a newer SATA disk with a WWN while /dev/sdc
is a SAS disk which all have WWNs (a.k.a. "Logical unit name").
The 'lsscsi --transport' output is showing the transport type (as
seen by Linux (hence "sas" for /dev/sdb))
and the target port identifier (which in SAS is a SAS address).
Notice the WWN and target port identifier for /dev/sdc
are close but not the same. The situation for a SATA disk behind a
SAS expander is a little different for the target port identifier
(look at the '--wwn' and '--transport' output for /dev/sdb),
as the SAS expander "makes up" the target port identifier.
The enclosure at 6:0:2:0 is closely associated with the SAS expander
and the enclosure actually does have a WWN but udev (as used by
lsscsi to data-mine the /dev directory) does not make it available,
so it is not displayed. The sg_vpd utility (with the '-i' option) can
be used to find the enclosure's WWN.
Version 0.27 added
the '--lunhex' option (short form: '-x'). Below are some examples,
the first shows the last element of the tuple when the '--lunhex'
option is not given:
#
lsscsi -g
[0:0:0:0] disk
ATA INTEL SSDSC2CW12 400i
/dev/sda /dev/sg0
[7:0:0:1]
disk Linux scsi_debug
0004 /dev/sdb /dev/sg1
[7:0:0:49409]wlun
Linux scsi_debug
0004 -
/dev/sg2
# lsscsi -g --lunhex
[0:0:0:0x0000]
disk ATA INTEL
SSDSC2CW12 400i /dev/sda /dev/sg0
[7:0:0:0x0001]
disk Linux scsi_debug
0004 /dev/sdb /dev/sg1
[7:0:0:0xc101]
wlun Linux scsi_debug
0004 -
/dev/sg2
# lsscsi -xx
[0:0:0:0x0000000000000000]
disk ATA INTEL
SSDSC2CW12 400i /dev/sda
[7:0:0:0x0001000000000000]
disk Linux scsi_debug
0004 /dev/sdb
[7:0:0:0xc101000000000000] wlun
Linux scsi_debug
0004 -
Version 0.27 added the
'--scsi_id' option (short form: '-i'):
#
lsscsi -i
[0:0:0:0] disk
ATA INTEL SSDSC2CW12 400i
/dev/sda SATA_INTEL_SSDSC2CW1CVCV
[6:0:0:1]
disk Linux scsi_debug
0004 /dev/sdb
353333330000036b1
[6:0:0:49409]wlun Linux
scsi_debug 0004 -
-
Version 0.28 added the '--unit' option
(short form: '-u'). It outputs the LU name as provided by the device
identification VPD page, or the WWN for SATA disks. That VPD
page became available in lk 3.15 so this option will not work (i.e.
outputs spaces) for older kernels. For a mixed SAS (with expanders)
and SATA environment that has these manufacturer, product, revision
strings:
#
lsscsi
[3:0:0:0] disk
ATA ST3160812AS
D /dev/sda
[6:0:0:0]
disk SEAGATE ST32000444SS
0008 /dev/sdf
[6:0:1:0] enclosu
Areca ARC-802801.13.1D 0113 -
[6:0:2:0] disk ATA
ST500LM000-1EJ16 DEM6 /dev/sdg
[6:0:3:0]
enclosu Intel RES2SV240
0d00 -
[6:0:4:0]
disk ATA
ST3500418AS CC34 /dev/sdh
The
LU names can look like this:
#
lsscsi -u
[3:0:0:0]
disk
/dev/sda
[6:0:0:0] disk
5000c500215925bf
/dev/sdf
[6:0:1:0] enclosu
5001b4d516e9c03d
-
[6:0:2:0]
disk 5000c50072e9d0c4
/dev/sdg
[6:0:3:0] enclosu
5001517e85c9effd
-
[6:0:4:0]
disk 5000c5001209fe84
/dev/sdh
The
first disk is a relatively old SATA disk that does not have a WWN,
hence the blanks. An example of using '-u' with an iSCSI device is
given in the Overview section. When '--unit' is compared with '--wwn'
it can be seen that the former is more general and is now preferred.
For example '--unit' will show the LU name of non-disk devices such
as enclosures and handle iSCSI devices (but the '--wwn' option will
not).
Support for NVMe device was added in lsscsi version 0.30 . For examples of its use, see the PCIe transport section above.
Here is a table of the versions of lsscsi available for the lk 2.6
and 3 series.
tarball |
binary rpm + deb |
source rpm |
notes |
suitable for lk 2.6.1 |
|||
lk 2.6.6, add '-d' for device major+minor |
|||
|
|
lk 2.6.7 add timeout value to --long option |
|
port to use sysfsutils-1.2.0 or later |
|||
lk 2.6.12 with optional select arguments and /dev scanning. Does not use libsysfs. |
|||
lk 2.6.14, fixes for osst and ch devices, Debian build. Does not use libsysfs. |
|||
lk 2.6.16, kernel (sysfs) change that first appeared in lk 2.6.16-rc1 requires this version to see block devices |
|||
allow for "generic" and "tape" symlinks to be dropped in sysfs. |
|||
lsscsi-0.19.tgz |
add transport information, '--list' option, fixes for lk 2.6.20 |
||
lsscsi-0.20.tgz |
for lk 2.6.26 when CONFIG_SYSFS_DEPRECATED_V2 |
||
lsscsi-0.21.tgz |
more changes for lk 2.6.26 |
||
lsscsi-0.22.tgz |
show protection information with '--protection' option, ATA, SATA and USB transport information |
||
lsscsi-0.23.tgz |
stop scanning /proc/mounts; assume /sys unless overridden by '--sysfsroot=PATH' option |
||
lsscsi-0.24.tgz |
add "(null)" to the currently accepted "<NULL>" as the string representation of NULL; FC transport syntax changes (colon to slash). Needed around lk 2.6.32 and later |
||
lsscsi-0.25.tgz |
add --size and --protmode options |
||
lsscsi-0.26.tgz |
add --wwn option and support for FCoE |
||
lsscsi-0.27.tgz |
lsscsi-0.27-1.i386.rpm |
add --lunhex (-x) option: accept Linux LUN numbers from sysfs as large as 64 bits. Add scsi_id (-i) option: udev derived information from /dev/disk/by-id/ . Improve handling of large number of disks. |
|
lsscsi-0.28.tgz |
lsscsi-0.28-1.i386.rpm |
add --unit (-u) option: display LU name or WWN for ATA disks; requires lk >= 3.15 . |
|
lsscsi-0.29.tgz |
|
|
|
lsscsi-0.30.tgz |
add NVMe support which is indicated by a tuple of [N:*:*:*] or [N:*]. Add --brief and --pdt options to aid parsing plus the --sz-lbs option |
||
|
20200220 |
|
|
Mainly a bug fix version |
|
20210505 |
print nr_hw_queues when available for SCSI hosts; improve NVMe device parsing; logic to select best SCSI id (--scsi_id) to output |
Here is the most recent ChangeLog .
To build from the tarball, extract its contents, move to the top level directory in the extracted sub-tree then do './configure ; make ; make install', Normal autotools conventions apply. If some configuration files are altered then the ./autogen.sh script may need to be called. The ./build_debian.sh script is provided to create a Debian package. A lsscsi.spec file is provided to facilitate building a "rpm" style package.
The lsscsi package is developed by the author using subversion. Subversion revisions, which are ascending integers, can be seen in the ChangeLog file and the version string (i.e. 'lsscsi -V') . Some users have asked for git access and a contributor has set up a git mirror on github:
Updates are sent to that mirror whenever a beta is placed on the main page, perhaps more often than that. Please report any problems to the author.
Return to main page.
Douglas Gilbert (dgilbert@interlog.com)
Last updated: 5th May 2021