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LSBLK(8)                     System Administration                    LSBLK(8)

NAME
       lsblk - list block devices

SYNOPSIS
       lsblk [options] [device...]

DESCRIPTION
       lsblk  lists information about all available or the specified block de-
       vices.  The lsblk command reads the sysfs filesystem  and  udev  db  to
       gather  information.  If  the udev db is not available or lsblk is com-
       piled without udev support than it tries  to  read  LABELs,  UUIDs  and
       filesystem  types  from the block device. In this case root permissions
       are necessary.

       The command prints all block devices (except RAM disks) in a  tree-like
       format  by  default.   Use  lsblk --help to get a list of all available
       columns.

       The default output, as well as the default  output  from  options  like
       --fs  and  --topology, is subject to change.  So whenever possible, you
       should avoid using default outputs in your scripts.  Always  explicitly
       define  expected  columns  by using --output columns-list and --list in
       environments where a stable output is required.

       Note that lsblk might be executed in time when udev does not  have  all
       information  about recently added or modified devices yet. In this case
       it is recommended to use udevadm settle  before  lsblk  to  synchronize
       with udev.

OPTIONS
       -a, --all
              Also list empty devices and RAM disk devices.

       -b, --bytes
              Print  the  SIZE column in bytes rather than in a human-readable
              format.

       -D, --discard
              Print information about the discarding capabilities  (TRIM,  UN-
              MAP) for each device.

       -d, --nodeps
              Do  not  print  holder  devices  or  slaves.  For example, lsblk
              --nodeps /dev/sda prints information about the sda device only.

       -E, --dedup column
              Use column as a de-duplication key to de-duplicate output  tree.
              If  the  key is not available for the device, or the device is a
              partition and parental whole-disk device provides the  same  key
              than the device is always printed.

              The  usual  use  case is to de-duplicate output on system multi-
              path devices, for example by -E WWN.

       -e, --exclude list
              Exclude the devices specified by the comma-separated list of ma-
              jor  device numbers.  Note that RAM disks (major=1) are excluded
              by default if --all is not specified.  The filter is applied  to
              the  top-level  devices  only.  This may be confusing for --list
              output format where hierarchy of the devices is not obvious.

       -f, --fs
              Output info about filesystems.  This  option  is  equivalent  to
              -o NAME,FSTYPE,LABEL,UUID,MOUNTPOINT.   The authoritative infor-
              mation about filesystems and raids is provided by  the  blkid(8)
              command.

       -h, --help
              Display help text and exit.

       -I, --include list
              Include  devices  specified by the comma-separated list of major
              device numbers.  The filter is applied to the top-level  devices
              only. This may be confusing for --list output format where hier-
              archy of the devices is not obvious.

       -i, --ascii
              Use ASCII characters for tree formatting.

       -J, --json
              Use JSON output format.  It's strongly recommended to use --out-
              put and also --tree if necessary.

       -l, --list
              Produce  output  in the form of a list. The output does not pro-
              vide information about relationships between devices  and  since
              version 2.34 every device is printed only once.

       -M, --merge
              Group  parents  of sub-trees to provide more readable output for
              RAIDs and Multi-path devices. The tree-like output is required.

       -m, --perms
              Output info about device owner, group and mode.  This option  is
              equivalent to -o NAME,SIZE,OWNER,GROUP,MODE.

       -n, --noheadings
              Do not print a header line.

       -o, --output list
              Specify which output columns to print.  Use --help to get a list
              of all supported columns.  The columns may affect tree-like out-
              put.  The default is to use tree for the column 'NAME' (see also
              --tree).

              The default list of columns may be extended if list is specified
              in the format +list (e.g. lsblk -o +UUID).

       -O, --output-all
              Output all available columns.

       -P, --pairs
              Produce  output  in  the  form of key="value" pairs.  All poten-
              tially unsafe characters are hex-escaped (\x<code>).

       -p, --paths
              Print full device paths.

       -r, --raw
              Produce output in raw format.  All potentially unsafe characters
              are  hex-escaped (\x<code>) in the NAME, KNAME, LABEL, PARTLABEL
              and MOUNTPOINT columns.

       -S, --scsi
              Output info about SCSI devices only.  All partitions, slaves and
              holder devices are ignored.

       -s, --inverse
              Print dependencies in inverse order. If the --list output is re-
              quested then the lines are still ordered by dependencies.

       -T, --tree[=column]
              Force tree-like output format.  If column is specified,  then  a
              tree is printed in the column.  The default is NAME column.

       -t, --topology
              Output info about block-device topology.  This option is equiva-
              lent       to       -o NAME,ALIGNMENT,MIN-IO,OPT-IO,PHY-SEC,LOG-
              SEC,ROTA,SCHED,RQ-SIZE,RA,WSAME.

       -V, --version
              Display version information and exit.

       -x, --sort column
              Sort  output  lines by column. This option enables --list output
              format by default.  It is possible to use the option  --tree  to
              force  tree-like output and than the tree branches are sorted by
              the column.

       -z, --zoned
              Print the zone model for each device.

        --sysroot directory
              Gather data for a Linux instance other than  the  instance  from
              which  the  lsblk command is issued.  The specified directory is
              the system root of the Linux instance to be inspected.  This op-
              tion is designed for the testing purpose.

NOTES
       For  partitions,  some information (e.g. queue attributes) is inherited
       from the parent device.

       The lsblk command needs to be able to look up each block device by  ma-
       jor:minor  numbers,  which is done by using /sys/dev/block.  This sysfs
       block directory appeared in kernel 2.6.27 (October 2008).  In  case  of
       problems  with a new enough kernel, check that CONFIG_SYSFS was enabled
       at the time of the kernel build.

RETURN CODES
       0      success

       1      failure

       32     none of specified devices found

       64     some specified devices found, some not found

AUTHORS
       Milan Broz <mbroz@redhat.com>
       Karel Zak <kzak@redhat.com>

ENVIRONMENT
       LSBLK_DEBUG=all
              enables lsblk debug output.

       LIBBLKID_DEBUG=all
              enables libblkid debug output.

       LIBMOUNT_DEBUG=all
              enables libmount debug output.

       LIBSMARTCOLS_DEBUG=all
              enables libsmartcols debug output.

       LIBSMARTCOLS_DEBUG_PADDING=on
              use  visible  padding  characters.  Requires  enabled  LIBSMART-
              COLS_DEBUG.

SEE ALSO
       ls(1), blkid(8), findmnt(8)

AVAILABILITY
       The  lsblk  command  is part of the util-linux package and is available
       from https://www.kernel.org/pub/linux/utils/util-linux/.

util-linux                       February 2013                        LSBLK(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | NOTES | RETURN CODES | AUTHORS | ENVIRONMENT | SEE ALSO | AVAILABILITY