lsscsi(8)                             LSSCSI                             lsscsi(8)

NAME
       lsscsi - list SCSI devices (or hosts) and their attributes

SYNOPSIS
       lsscsi  [--classic]  [--device]  [--generic]  [--help]  [--hosts] [--kname]
       [--list]  [--lunhex]  [--long]  [--protection]   [--protmode]   [--scsi_id]
       [--size]  [--sysfsroot=PATH]  [--transport] [--verbose] [--version] [--wwn]
       [H:C:T:L]

DESCRIPTION
       Uses information in sysfs (Linux kernel series 2.6 and later) to list  SCSI
       devices (or hosts) currently attached to the system. Options can be used to
       control the amount and form of information provided for each device.

       If a H:C:T:L argument is given then it acts as a filter  and  only  devices
       that  match  it  are  listed. The colons don't have to be present, and '-',
       '*', '?' or missing arguments at the end are interpreted as wildcards.  The
       default  is  '*:*:*:*'  which  means to match everything. Any filter string
       using '*' of '?' should be surrounded by single or double  quotes  to  stop
       shell  expansions. If '-' is used as a wildcard then the whole filter argu‐
       ment should be prefixed by '-- ' to tell this utility  there  are  no  more
       options  on the command line to be interpreted.  A leading '[' and trailing
       ']' are permitted (e.g. '[1:0:0]' matches all LUNs on 1:0:0). May  also  be
       used to filter --hosts in which case only the H is active and may be either
       a number or in the form "host<n>" where <n> is a host number.

       By  default  in  this  utility  device  node  names  (e.g.  "/dev/sda"   or
       "/dev/root_disk")  are  obtained  by noting the major and minor numbers for
       the  listed  device   obtained   from   sysfs   (e.g.   the   contents   of
       "/sys/block/sda/dev") and then looking for a match in the "/dev" directory.
       This "match by major and minor" will allow devices that have been  given  a
       different name by udev (for example) to be correctly reported by this util‐
       ity.

       In some situations it may be useful to see the device node name that  Linux
       would produce by default, so the --kname option is provided.  An example of
       where this may be useful is kernel error logs which  tend  to  report  disk
       error messages using the disk's default kernel name.

OPTIONS
       Arguments  to  long  options  are mandatory for short options as well.  The
       options are arranged in alphabetical order based on the long option name.

       -c, --classic
              The output is similar to that obtained from 'cat /proc/scsi/scsi'

       -d, --device
              After outputting the (probable) SCSI device  name  the  device  node
              major    and   minor   numbers   are   shown   in   brackets   (e.g.
              "/dev/sda[8:0]").

       -g, --generic
              Output the SCSI generic device file name. Note that if the sg driver
              is a module it may need to be loaded otherwise '-' may appear.

       -h, --help
              Output the usage message and exit.

       -H, --hosts
              List the SCSI hosts currently attached to the system. If this option
              is not given then SCSI devices are listed.

       -k, --kname
              Use Linux default algorithm for naming devices (e.g. block major  8,
              minor 0 is "/dev/sda") rather than the "match by major and minor" in
              the "/dev" directory as discussed above.

       -L, --list
              Output additional information in <attribute_name>=<value> pairs, one
              pair  per  line  preceded  by  two  spaces. This option has the same
              effect as '-lll'.

       -l, --long
              Output additional information for each SCSI device  (host).  Can  be
              used multiple times for more output in which case the shorter option
              form is more convenient (e.g. '-lll'). When used three  times  (i.e.
              '-lll') outputs SCSI device (host) attributes one per line; preceded
              by two spaces; in the form "<attribute_name>=<value>".

       -x, --lunhex
              when this option is used once the LUN in the tuple (at the start  of
              each  device  line) is shown in "T10" format which is up to 16 hexa‐
              decimal digits. It is prefixed by "0x" to distinguish the  LUN  from
              the  decimal value shown in the absence of this option. Also hierar‐
              chal LUNs are shown with a "_" character separating the levels.  For
              example  the  two  level  LUN:  0x0355006600000000  will  appear  as
              0x0355_0066. If this option is given twice  (e.g.  using  the  short
              form:  '-xx') then the full 16 hexadecimal digits are shown for each
              LUN, prefixed by "0x".

       -p, --protection
              Output target (DIF) and initiator (DIX) protection types.

       -P, --protmode
              Output effective protection information mode for each disk device.

       -i, --scsi_id
              outputs the udev derived matching id found in  /dev/disk/by-id/scsi*
              .   This  is  only  for disk (and disk like) devices. If no match is
              found then "dm-uuid-mpath*" and "usb*"  are  searched  in  the  same
              directory.     If    there    is    still    no   match   then   the
              /sys/class/block/<disk>/holders directory is searched. The  matching
              id  is  printed  following  the  device name (e.g.  /dev/sdc) and if
              there is no match "-" is output.

       -s, --size
              Print disk capacity in human readable form.

       -t, --transport
              Output transport information. This will be a target related informa‐
              tion  or,  if  --hosts is given, initiator related information. When
              used without --list, a name or identifier (or both) are output on  a
              single  line, usually prefixed by the type of transport. For devices
              this information replaces the normal vendor,  product  and  revision
              strings. When the --list option is also given then additionally mul‐
              tiple lines of attribute_name=value pairs are output, each  indented
              by two spaces. See the section on transports below.

       -v, --verbose
              outputs  directory  names  where  information is found. Use multiple
              times for more output.

       -V, --version
              outputs version information then exits.

       -w, --wwn
              outputs the WWN for disks instead of manufacturer, model  and  revi‐
              sion  (or  instead  of  transport  information). The World Wide Name
              (WWN) is typically 64 bits long (16 hex digits) but could be  up  to
              128 bits long. To indicate the WWN is hexadecimal, it is prefixed by
              "0x".

       -y, --sysfsroot=PATH
              assumes sysfs is mounted at PATH instead of the default '/sys' .  If
              this  option  is  given  PATH should be an absolute path (i.e. start
              with '/').

TRANSPORTS
       This utility lists SCSI devices which are known as logical  units  (LU)  in
       the  SCSI  Architecture  Model  (ref: SAM-4 at http://www.t10.org) or hosts
       when the --hosts option is given. A host is called an initiator in SAM-4. A
       SCSI  command travels out via an initiator, across some transport to a tar‐
       get and then onwards to a logical unit. A target device may contain several
       logical  units. A target device has one or more ports that can be viewed as
       transport end points. Each FC and SAS disk is a single target that has  two
       ports  and  contains  one logical unit. If both target ports on a FC or SAS
       disk are connected and visible to a machine,  then  lsscsi  will  show  two
       entries.  Initiators (i.e. hosts) also have one or more ports and some HBAs
       in Linux have a host entry per initiator port  while  others  have  a  host
       entry per initiator device.

       When  the --transport option is given for devices (i.e.  --hosts not given)
       then most of the information produced by lsscsi is associated with the tar‐
       get,  or  more precisely: the target port, through which SCSI commands pass
       that access a logical unit.

       Typically this utility provides one line of output per  "device"  or  host.
       Significantly more information can be obtained by adding the --list option.
       When used together with the --transport option,  after  the  summary  line,
       multiple   lines   of   transport   specific   information   in   the  form
       "<attribute_name>=<value>" are output, each indented by two spaces.   Using
       a  filter  argument will reduce the volume of output if a lot of devices or
       hosts are present.

       The transports that are currently  recognized  are:  IEEE  1394,  ATA,  FC,
       iSCSI, SAS, SATA, SPI and USB.

       For  IEEE  1394  (a.k.a.  Firewire and "SBP" when storage is involved), the
       EUI-64 based target port name is output when --transport is given,  in  the
       absence  of  the  --hosts option. When the --hosts option is given then the
       EUI-64 initiator port name is output. Output on the summary  line  specific
       to the IEEE 1394 transport is prefixed by "sbp:".

       to detect ATA and SATA a crude check is performed on the driver name (after
       the checks for other transports are exhausted). Based on  the  driver  name
       either  ATA or SATA transport type is chosen. Output on the summary line is
       either "ata:" or "sata:". No other attributes are given.  Most  device  and
       hosts flagged as "ata:" will use the parallel ATA transport (PATA).

       For  Fibre  Channel  (FC) the port name and port identifier are output when
       --transport is given. In the absence of the --hosts option these  ids  will
       be  for  the  target  port  associated with the device (logical unit) being
       listed. When the --hosts option is given then the ids are for the initiator
       port used by the host. Output on the summary line specific to the FC trans‐
       port is prefixed by "fc:".  If FCoE (over Ethernet) is detected the  prefix
       is changed to "fcoe:".

       For  iSCSI the target port name is output when --transport is given, in the
       absence of the --hosts option. This is made up of the iSCSI  name  and  the
       target  portal group tag. Since the iSCSI name starts with "iqn" no further
       prefix is used. When the --hosts option is given then only "iscsi:" is out‐
       put on the summary line.

       For  Serial  Attached SCSI the SAS address of the target port (or initiator
       port if --hosts option is also given) is  output.  This  will  be  a  naa-5
       address.  For  SAS HBAs and SAS targets (such as SAS disks and tape drives)
       the SAS address will be world wide unique. For SATA disks attached to a SAS
       expander,  the expander provides the SAS address by adding a non zero value
       to its (i.e. the  expander's)  SAS  address  (e.g.  expander_sas_address  +
       phy_id + 1). SATA disks directly attached to SAS HBAs seem to have an inde‐
       terminate SAS address. Output on the  summary  line  specific  to  the  SAS
       transport is prefixed by "sas:".

       For the SCSI Parallel Interface (SPI) the target port identifier (usually a
       number between 0 and 15 inclusive) is output when --transport is given,  in
       the  absence  of  the --hosts option. When the --hosts option is given then
       only "spi:" is output on the summary line.

       When a USB transport is detected, the summary line will contain "usb:" fol‐
       lowed   by   a   USB  device  name.  The  USB  device  name  has  the  form
       "<b>-<p1>[.<p2>[.<p3>]]:<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 a 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 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.

LUNS
       For  historical  reasons  and as used by several other Unix based Operating
       Systems, Linux uses a tuple of integers to describe  (a  path  to)  a  SCSI
       device  (also  know as a Logical Unit (LU)). The last element of that tuple
       is the so-called Logical Unit Number (LUN). And originally in  SCSI  a  LUN
       was  an integer, at first 3 bits long, then 8 then 16 bits. SCSI LUNs today
       (SAM-5 section 4.7) are 64 bits but SCSI standards now consider a LUN to be
       an array of 8 bytes.

       Up  until  2013,  Linux  mapped SCSI LUNs to a 32 bit integer by taking the
       first 4 bytes of the SCSI LUN and ignoring the last 4 bytes. Linux  treated
       the  first  two  bytes of the SCSI LUN as a unit (a word) and it became the
       least significant 16 bits in the Linux LUN integer. The next two  bytes  of
       the  SCSI LUN became the upper 16 bits in the Linux LUN integer. The ratio‐
       nale for this was to keep commonly used LUNs small Linux LUN integers.  The
       most common LUN (by far) in SCSI LUN (hex) notation is 00 00 00 00 00 00 00
       00 and this becomes the Linux LUN integer 0. The next most common LUN is 00
       01 00 00 00 00 00 00 and this becomes the Linux LUN integer 1.

       In  2013  it  is  proposed  to  increase  Linux LUNs to a 64 bit integer by
       extending the mapping outlined above. In this case all information that  is
       possible to represent in a SCSI LUN is mapped a Linux LUN (64 bit) integer.
       And the mapping can be reversed without losing information.

       This version of the utility supports both 32 and 64 bit Linux LUN integers.
       By  default the LUN shown at the end of the tuple commencing each line is a
       Linux LUN as a decimal integer. When the --lunhex option is given then  the
       LUN is in SCSI LUN format with the 8 bytes run together, with the output in
       hexadecimal and prefixed by '0x'. The LUN is decoded according  to  SAM-5's
       description and trailing zeros (i.e. digits to the right) are not shown. So
       LUN 0 (i.e. 00 00 00 00 00 00 00 00) is shown as 0x0000 and LUN 65 (i.e. 00
       41  00 00 00 00 00 00) is shown as 0x0041.  If the --lunhex option is given
       twice then the full 64 bits (i.e. 16 hexadecimal digits) are shown.

       If the --lunhex option is not given on the command line then  the  environ‐
       ment variable LSSCSI_LUNHEX_OPT is checked. If LSSCSI_LUNHEX_OPT is present
       then its associated value becomes the number of times the --lunhex  is  set
       internally. So, for example, 'LSSCSI_LUNHEX_OPT=2  lsscsi' and 'lsscsi -xx'
       are equivalent.

EXAMPLES
       Information about this utility including examples can  also  be  found  at:
       http://sg.danny.cz/scsi/lsscsi.html .

NOTES
       Information  for  this command is derived from the sysfs file system, which
       is assumed to be mounted at /sys unless specified otherwise  by  the  user.
       SCSI (pseudo) devices that have been detected by the SCSI mid level will be
       listed even if the required upper level drivers (i.e. sd, sr, st,  osst  or
       ch)  have  not  been  loaded. If the appropriate upper level driver has not
       been loaded then the device file name will appear as '-' rather than  some‐
       thing  like  '/dev/st0'.  Note  that some devices (e.g. scanners and medium
       changers) do not have a primary upper level driver and can only be accessed
       via a SCSI generic (sg) device name.

       Generic  SCSI devices can also be accessed via the bsg driver in Linux.  By
       default,  the  bsg  driver's  device   node   names   are   of   the   form
       '/dev/bsg/H:C:T:L'.  So, for example, the SCSI device shown by this utility
       on a line starting with the tuple '6:0:1:2' could be accessed via  the  bsg
       driver with the '/dev/bsg/6:0:1:2' device node name.

       lsscsi  version 0.21 or later is required to correctly display SCSI devices
       in Linux kernel 2.6.26 (and possibly later)  when  the  CONFIG_SYSFS_DEPRE‐
       CATED_V2 kernel option is not defined.

AUTHOR
       Written by Doug Gilbert

REPORTING BUGS
       Report bugs to <dgilbert at interlog dot com>.

COPYRIGHT
       Copyright © 2003-2013 Douglas Gilbert
       This software is distributed under the GPL version 2. There is NO warranty;
       not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

SEE ALSO
       lspci lsusb

lsscsi-0.27                         March 2013                           lsscsi(8)

Usage: lsscsi   [--classic] [--device] [--generic] [--help] [--hosts]
                [--kname] [--list] [--lunhex] [--long] [--protection]
                [--scsi_id] [--size] [--sysfsroot=PATH] [--transport]
                [--verbose] [--version] [--wwn] [<h:c:t:l>]
  where:
    --classic|-c      alternate output similar to 'cat /proc/scsi/scsi'
    --device|-d       show device node's major + minor numbers
    --generic|-g      show scsi generic device name
    --help|-h         this usage information
    --hosts|-H        lists scsi hosts rather than scsi devices
    --kname|-k        show kernel name instead of device node name
    --list|-L         additional information output one
                      attribute=value per line
    --long|-l         additional information output
    --lunhex|-x       show LUN part of tuple as hex number in T10 format;
                      use twice to get full 16 digit hexadecimal LUN
    --protection|-p   show target and initiator protection information
    --protmode|-P     show negotiated protection information mode
    --scsi_id|-i      show udev derived /dev/disk/by-id/scsi* entry
    --size|-s         show disk size
    --sysfsroot=PATH|-y PATH    set sysfs mount point to PATH (def: /sys)
    --transport|-t    transport information for target or, if '--hosts'
                      given, for initiator
    --verbose|-v      output path names where data is found
    --version|-V      output version string and exit
    --wwn|-w          output WWN for disks (from /dev/disk/by-id/wwn*)
    <h:c:t:l>         filter output list (def: '*:*:*:*' (all))

List SCSI devices or hosts, optionally with additional information