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lsblk(8) [bsd man page]

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 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 environ-
       ments 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/.

util-linux							   February 2013							  LSBLK(8)

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