bionic (8) lsblk.8.gz

NAME

       lsblk - list block devices

SYNOPSIS

       lsblk [options] [device...]

DESCRIPTION

       lsblk  lists information about all available or the specified block devices.  The lsblk command reads the
       sysfs filesystem and udev db to gather information. If the udev db is not available or lsblk is  compiled
       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 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.  (By default they are skipped.)

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

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

       -z, --zoned
              Print the zone model 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, --exclude list
              Exclude the devices specified by the comma-separated list of major device numbers.  Note that  RAM
              disks (major=1) are excluded by default.  The filter is applied to the top-level devices only.

       -f, --fs
              Output info about filesystems.  This option is equivalent to -o NAME,FSTYPE,LABEL,UUID,MOUNTPOINT.
              The authoritative information 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.

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

       -J, --json
              Use JSON output format.

       -l, --list
              Produce output in the form of a list.

       -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 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 potentially 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 requested then the lines are still
              ordered by dependencies.

       -t, --topology
              Output info about block-device topology.  This  option  is  equivalent  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.

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 major: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

       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 LIBSMARTCOLS_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/.