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.
