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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
       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.

       By default, the command prints all block devices (except RAM disks) in a
       tree-like format. The same device can be repeated in the tree if it
       relates to other devices. The --merge option is recommended for more
       complicated setups to gather groups of devices and describe complex N:M
       relationships.

       The tree-like output (or children[] array in the JSON output) is enabled
       only if NAME column it present in the output or when --tree command line
       option is used. See also --nodeps and --list to control the tree
       formatting.

       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.

       Use lsblk --list-columns to get a list of all available columns.

       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
       -A, --noempty
           Don’t print empty devices.

       -a, --all
           Disable all built-in filters and list all empty devices and RAM disk
           devices too.

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

           By default, the unit, sizes are expressed in, is byte, and unit
           prefixes are in power of 2^10 (1024). Abbreviations of symbols are
           exhibited truncated in order to reach a better readability, by
           exhibiting alone the first letter of them; examples: "1 KiB" and "1
           MiB" are respectively exhibited as "1 K" and "1 M", then omitting on
           purpose the mention "iB", which is part of these abbreviations.

       -H, --list-columns
           List the available columns, use with --json or --raw to get output
           in machine-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.

       --hyperlink[=mode]
           Print mountpoint paths as terminal hyperlinks. The mode can be set
           to "always", "never", or "auto". The optional argument when can be
           set to "auto", "never", or "always". If the when argument is
           omitted, it will default to "auto". The "auto" setting means that
           hyperlinks will only be used if the output is on a terminal.

       -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. Note that children[] is used only if
           NAME column or --tree is used.

       -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, --nvme
           Output info about NVMe devices only.

       -v, --virtio
           Output info about virtio devices only.

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

       -o, --output list
           Specify which output columns to print. Use --list-columns 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>). See also option --shell.

       -p, --paths
           Print full device paths.

       -Q, --filter expr
           Print only the devices that meet the conditions specified by the
           expr. The filter is assessed prior to lsblk collecting data for all
           output columns. Only the necessary data for the lazy evaluation of
           the expression is retrieved from the system. This approach can
           enhance performance when compared to post-filtering, as commonly
           done by tools such as grep(1).

           This feature is EXPERIMENTAL. See also scols-filter(5). For example
           exclude sda  and sdb, but print everything else ('!~' is a negative
           regular expression matching operator):

              lsblk --filter 'NAME !~ "sd[ab]"'

       --highlight expr
           Colorize lines matching the expression. This feature is
           EXPERIMENTAL. See also scols-filter(5).

       --ct name [: param [: function ]]
           Define a custom counter. The counters are printed after the standard
           output. The name is the custom name of the counter, the optional
           param is the name of the column to be used for the counter, and the
           optional function specifies the aggregation function, supported
           functions are: count, min, max, or sum. The default is count.

           If the param is not specified, then the counter counts the number of
           lines. This feature is EXPERIMENTAL. See also --ct-filter.

           For example, --ct MyCounter:SIZE:sum will count the summary for SIZE
           from all lines; and to count the number of SATA disks, it is
           possible to use:

              lsblk --ct-filter 'TYPE=="disk" && TRAN=="sata"' --ct "Number of SATA devices"

       --ct-filter expr
           Define a restriction for the next counter. This feature is
           EXPERIMENTAL. See also --ct and scols-filter(5). For example,
           aggregate sizes by device type:

              lsblk --ct-filter 'TYPE=="part"' --ct Partitions:SIZE:sum \
                    --ct-filter 'TYPE=="disk"' --ct WholeDisks:SIZE:sum

       -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.

       -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.

       -y, --shell
           The column name will be modified to contain only characters allowed
           for shell variable identifiers, for example, MIN_IO and FSUSE_PCT
           instead of MIN-IO and FSUSE%. This is usable, for example, with
           --pairs. Note that this feature has been automatically enabled for
           --pairs in version 2.37, but due to compatibility issues, now it’s
           necessary to request this behavior by --shell.

       -z, --zoned
           Print the zone related information 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.

       --properties-by list
           This option specifies the methods used by lsblk to gather
           information about filesystems and partition tables. The list is a
           comma-separated list of method names. The default setting is
           "file,udev,blkid". The supported methods are:

           udev
               Reads data from udev DB. If unsuccessful, it continues to the
               next probing method.

           blkid
               Reads data directly from the device using libblkid. If
               unsuccessful, it continues to the next probing method.

           file
               Reads data from a file. This method is only used if the
               --sysroot option is specified. This method always stops probing
               if used.

           none
               Does not probe. This method always stops probing.

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

       -V, --version
           Display version and exit.

EXIT STATUS
       0
           success

       1
           failure

       32
           none of specified devices found

       64
           some specified devices found, some not found

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.

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.

AUTHORS
       Milan Broz <gmazyland@gmail.com>, Karel Zak <kzak@redhat.com>

SEE ALSO
       blkid(8), findmnt(8) ls(1), scols-filter(5)

REPORTING BUGS
       For bug reports, use the issue tracker
       <https://github.com/util-linux/util-linux/issues>.

AVAILABILITY
       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/>.

util-linux 2.41                    2025-03-17                          LSBLK(8)

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