1LSBLK(8) System Administration LSBLK(8)
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6 lsblk - list block devices
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9 lsblk [options] [device...]
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12 lsblk lists information about all available or the specified block
13 devices. The lsblk command reads the sysfs filesystem and udev db to
14 gather information. If the udev db is not available or lsblk is
15 compiled without udev support, then it tries to read LABELs, UUIDs and
16 filesystem types from the block device. In this case root permissions
17 are necessary.
18 The command prints all block devices (except RAM disks) in a tree-like
20 format by default. Use lsblk --help to get a list of all available
21 columns.
22 The default output, as well as the default output from options like
24 --fs and --topology, is subject to change. So whenever possible, you
25 should avoid using default outputs in your scripts. Always explicitly
26 define expected columns by using --output columns-list and --list in
27 environments where a stable output is required.
28 Note that lsblk might be executed in time when udev does not have all
30 information about recently added or modified devices yet. In this case
31 it is recommended to use udevadm settle before lsblk to synchronize
32 with udev.
33 The relationship between block devices and filesystems is not always
35 one-to-one. The filesystem may use more block devices, or the same
36 filesystem may be accessible by more paths. This is the reason why
37 lsblk provides MOUNTPOINT and MOUNTPOINTS (pl.) columns. The column
38 MOUNTPOINT displays only one mount point (usually the last mounted
39 instance of the filesystem), and the column MOUNTPOINTS displays by
40 multi-line cell all mount points associated with the device.
41
43 -A, --noempty
44 Don’t print empty devices.
45 -a, --all
47 Disable all built-in filters and list all empty devices and RAM
48 disk devices too.
49 -b, --bytes
51 Print the sizes in bytes rather than in a human-readable format.
52 By default, the unit, sizes are expressed in, is byte, and unit
54 prefixes are in power of 2^10 (1024). Abbreviations of symbols are
55 exhibited truncated in order to reach a better readability, by
56 exhibiting alone the first letter of them; examples: "1 KiB" and "1
57 MiB" are respectively exhibited as "1 K" and "1 M", then omitting
58 on purpose the mention "iB", which is part of these abbreviations.
59 -D, --discard
61 Print information about the discarding capabilities (TRIM, UNMAP)
62 for each device.
63 -d, --nodeps
65 Do not print holder devices or slaves. For example, lsblk --nodeps
66 /dev/sda prints information about the sda device only.
67 -E, --dedup column
69 Use column as a de-duplication key to de-duplicate output tree. If
70 the key is not available for the device, or the device is a
71 partition and parental whole-disk device provides the same key than
72 the device is always printed.
73 The usual use case is to de-duplicate output on system multi-path
75 devices, for example by -E WWN.
76 -e, --exclude list
78 Exclude the devices specified by the comma-separated list of major
79 device numbers. Note that RAM disks (major=1) are excluded by
80 default if --all is not specified. The filter is applied to the
81 top-level devices only. This may be confusing for --list output
82 format where hierarchy of the devices is not obvious.
83 -f, --fs
85 Output info about filesystems. This option is equivalent to -o
86 NAME,FSTYPE,FSVER,LABEL,UUID,FSAVAIL,FSUSE%,MOUNTPOINTS. The
87 authoritative information about filesystems and raids is provided
88 by the blkid(8) command.
89 -I, --include list
91 Include devices specified by the comma-separated list of major
92 device numbers. The filter is applied to the top-level devices
93 only. This may be confusing for --list output format where
94 hierarchy of the devices is not obvious.
95 -i, --ascii
97 Use ASCII characters for tree formatting.
98 -J, --json
100 Use JSON output format. It’s strongly recommended to use --output
101 and also --tree if necessary.
102 -l, --list
104 Produce output in the form of a list. The output does not provide
105 information about relationships between devices and since version
106 2.34 every device is printed only once if --pairs or --raw not
107 specified (the parsable outputs are maintained in backwardly
108 compatible way).
109 -M, --merge
111 Group parents of sub-trees to provide more readable output for
112 RAIDs and Multi-path devices. The tree-like output is required.
113 -m, --perms
115 Output info about device owner, group and mode. This option is
116 equivalent to -o NAME,SIZE,OWNER,GROUP,MODE.
117 -n, --noheadings
119 Do not print a header line.
120 -o, --output list
122 Specify which output columns to print. Use --help to get a list of
123 all supported columns. The columns may affect tree-like output. The
124 default is to use tree for the column 'NAME' (see also --tree).
125 The default list of columns may be extended if list is specified in
127 the format +list (e.g., lsblk -o +UUID).
128 -O, --output-all
130 Output all available columns.
131 -P, --pairs
133 Produce output in the form of key="value" pairs. The output lines
134 are still ordered by dependencies. All potentially unsafe value
135 characters are hex-escaped (\x<code>). See also option --shell.
136 -p, --paths
138 Print full device paths.
139 -r, --raw
141 Produce output in raw format. The output lines are still ordered by
142 dependencies. All potentially unsafe characters are hex-escaped
143 (\x<code>) in the NAME, KNAME, LABEL, PARTLABEL and MOUNTPOINT
144 columns.
145 -S, --scsi
147 Output info about SCSI devices only. All partitions, slaves and
148 holder devices are ignored.
149 -s, --inverse
151 Print dependencies in inverse order. If the --list output is
152 requested then the lines are still ordered by dependencies.
153 -T, --tree[=column]
155 Force tree-like output format. If column is specified, then a tree
156 is printed in the column. The default is NAME column.
157 -t, --topology
159 Output info about block-device topology. This option is equivalent
160 to
161 -o
163 NAME,ALIGNMENT,MIN-IO,OPT-IO,PHY-SEC,LOG-SEC,ROTA,SCHED,RQ-SIZE,RA,WSAME.
164 -h, --help
166 Display help text and exit.
167 -V, --version
169 Print version and exit.
170 -w, --width number
172 Specifies output width as a number of characters. The default is
173 the number of the terminal columns, and if not executed on a
174 terminal, then output width is not restricted at all by default.
175 This option also forces lsblk to assume that terminal control
176 characters and unsafe characters are not allowed. The expected
177 use-case is for example when lsblk is used by the watch(1) command.
178 -x, --sort column
180 Sort output lines by column. This option enables --list output
181 format by default. It is possible to use the option --tree to force
182 tree-like output and than the tree branches are sorted by the
183 column.
184 -y, --shell
186 The column name will be modified to contain only characters allowed
187 for shell variable identifiers, for example, MIN_IO and FSUSE_PCT
188 instead of MIN-IO and FSUSE%. This is usable, for example, with
189 --pairs. Note that this feature has been automatically enabled for
190 --pairs in version 2.37, but due to compatibility issues, now it’s
191 necessary to request this behavior by --shell.
192 -z, --zoned
194 Print the zone related information for each device.
195 --sysroot directory
197 Gather data for a Linux instance other than the instance from which
198 the lsblk command is issued. The specified directory is the system
199 root of the Linux instance to be inspected. The real device nodes
200 in the target directory can be replaced by text files with udev
201 attributes.
202
204 0
205 success
206 1
208 failure
209 32
211 none of specified devices found
212 64
214 some specified devices found, some not found
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217 LSBLK_DEBUG=all
218 enables lsblk debug output.
219 LIBBLKID_DEBUG=all
221 enables libblkid debug output.
222 LIBMOUNT_DEBUG=all
224 enables libmount debug output.
225 LIBSMARTCOLS_DEBUG=all
227 enables libsmartcols debug output.
228 LIBSMARTCOLS_DEBUG_PADDING=on
230 use visible padding characters.
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233 For partitions, some information (e.g., queue attributes) is inherited
234 from the parent device.
235 The lsblk command needs to be able to look up each block device by
237 major:minor numbers, which is done by using /sys/dev/block. This sysfs
238 block directory appeared in kernel 2.6.27 (October 2008). In case of
239 problems with a new enough kernel, check that CONFIG_SYSFS was enabled
240 at the time of the kernel build.
241
243 Milan Broz <mbroz@redhat.com>, Karel Zak <kzak@redhat.com>
244
246 ls(1), blkid(8), findmnt(8)
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249 For bug reports, use the issue tracker at
250 https://github.com/util-linux/util-linux/issues.
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253 The lsblk command is part of the util-linux package which can be
254 downloaded from Linux Kernel Archive
255 <https://www.kernel.org/pub/linux/utils/util-linux/>.
256util-linux 2.38 2022-02-17 LSBLK(8)