lsblk(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | ENVIRONMENT | NOTES | AUTHORS | SEE ALSO | REPORTING BUGS | AVAILABILITY

LSBLK(8)                  System Administration                 LSBLK(8)

NAME         top

       lsblk - list block devices

SYNOPSIS         top

       lsblk [options] [device...]

DESCRIPTION         top

       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, then 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.

       The relationship between block devices and filesystems is not
       always one-to-one. The filesystem may use more block devices, or
       the same filesystem may be accessible by more paths. This is the
       reason why lsblk provides MOUNTPOINT and MOUNTPOINTS (pl.)
       columns. The column MOUNTPOINT displays only one mount point
       (usually the last mounted instance of the filesystem), and the
       column MOUNTPOINTS displays by multi-line cell all mount points
       associated with the device.

OPTIONS         top

       -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,
           UNMAP) 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
           major 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,FSVER,LABEL,UUID,FSAVAIL,FSUSE%,MOUNTPOINTS.
           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. This may be confusing for --list output format
           where hierarchy 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
           --output and also --tree if necessary.

       -l, --list
           Produce output in the form of a list. The output does not
           provide information about relationships between devices and
           since version 2.34 every device is printed only once if
           --pairs or --raw not specified (the parsable outputs are
           maintained in backwardly compatible way).

       -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 output. 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. The output
           lines are still ordered by dependencies. All potentially
           unsafe value characters are hex-escaped (\x<code>). The key
           (variable name) will be modified to contain only characters
           allowed for a shell variable identifiers, for example, MIN_IO
           and FSUSE_PCT instead of MIN-IO and FSUSE%.

       -p, --paths
           Print full device paths.

       -r, --raw
           Produce output in raw format. The output lines are still
           ordered by dependencies. 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, --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
           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.

       -w, --width number
           Specifies output width as a number of characters. The default
           is the number of the terminal columns, and if not executed on
           a terminal, then output width is not restricted at all by
           default. This option also forces lsblk to assume that
           terminal control characters and unsafe characters are not
           allowed. The expected use-case is for example when lsblk is
           used by the watch(1) command.

       -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. The
           real device nodes in the target directory can be replaced by
           text files with udev attributes.

EXIT STATUS         top

       0
           success

       1
           failure

       32
           none of specified devices found

       64
           some specified devices found, some not found

ENVIRONMENT         top

       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.

NOTES         top

       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.

AUTHORS         top

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

SEE ALSO         top

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

REPORTING BUGS         top

       For bug reports, use the issue tracker at
       https://github.com/karelzak/util-linux/issues.

AVAILABILITY         top

       The lsblk command is part of the util-linux package which can be
       downloaded from Linux Kernel Archive
       <https://www.kernel.org/pub/linux/utils/util-linux/>. This page
       is part of the util-linux (a random collection of Linux
       utilities) project. Information about the project can be found at
       ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have
       a bug report for this manual page, send it to
       util-linux@vger.kernel.org. This page was obtained from the
       project's upstream Git repository
       ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
       2021-08-27. (At that time, the date of the most recent commit
       that was found in the repository was 2021-08-24.) If you discover
       any rendering problems in this HTML version of the page, or you
       believe there is a better or more up-to-date source for the page,
       or you have corrections or improvements to the information in
       this COLOPHON (which is not part of the original manual page),
       send a mail to man-pages@man7.org

util-linux 2.37.294-0c7e       2021-08-19                       LSBLK(8)

Pages that refer to this page: eject(1)mount(2)fstab(5)blkdeactivate(8)blkid(8)cfdisk(8)findfs(8)mount(8)