Section (8) lsblk
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 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.
OPTIONS
−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.
−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 if
−−all
is no specified. The filter is applied to the top-level devices only. This maybe 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,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 maybe 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.
−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. - −−sysrootdirectory
-
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. This option is designed for the testing purpose.
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
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. Requires enabled LIBSMARTCOLS_DEBUG.