lsblk - list block devices
lsblk [options] [device...]
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 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.
- -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,LABEL,UUID,FSAVAIL,FSUSE%,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. 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 characters
are hex-escaped (\x<code>).
- -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.
- -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.
- 0
- success
- 1
- failure
- 32
- none of specified devices found
- 64
- some specified devices found, some not found
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.
Milan Broz <mbroz@redhat.com>
Karel Zak <kzak@redhat.com>
The lsblk command is part of the util-linux package and is
available from https://www.kernel.org/pub/linux/utils/util-linux/.