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.
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19 By default, the command prints all block devices (except RAM disks) in
20 a tree-like format. The same device can be repeated in the tree if it
21 relates to other devices. The --merge option is recommended for more
22 complicated setups to gather groups of devices and describe complex N:M
23 relationships.
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25 The default output, as well as the default output from options like
26 --fs and --topology, is subject to change. So whenever possible, you
27 should avoid using default outputs in your scripts. Always explicitly
28 define expected columns by using --output columns-list and --list in
29 environments where a stable output is required.
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31 Use lsblk --help to get a list of all available columns.
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33 Note that lsblk might be executed in time when udev does not have all
34 information about recently added or modified devices yet. In this case
35 it is recommended to use udevadm settle before lsblk to synchronize
36 with udev.
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38 The relationship between block devices and filesystems is not always
39 one-to-one. The filesystem may use more block devices, or the same
40 filesystem may be accessible by more paths. This is the reason why
41 lsblk provides MOUNTPOINT and MOUNTPOINTS (pl.) columns. The column
42 MOUNTPOINT displays only one mount point (usually the last mounted
43 instance of the filesystem), and the column MOUNTPOINTS displays by
44 multi-line cell all mount points associated with the device.
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47 -A, --noempty
48 Don’t print empty devices.
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50 -a, --all
51 Disable all built-in filters and list all empty devices and RAM
52 disk devices too.
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54 -b, --bytes
55 Print the sizes in bytes rather than in a human-readable format.
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57 By default, the unit, sizes are expressed in, is byte, and unit
58 prefixes are in power of 2^10 (1024). Abbreviations of symbols are
59 exhibited truncated in order to reach a better readability, by
60 exhibiting alone the first letter of them; examples: "1 KiB" and "1
61 MiB" are respectively exhibited as "1 K" and "1 M", then omitting
62 on purpose the mention "iB", which is part of these abbreviations.
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64 -D, --discard
65 Print information about the discarding capabilities (TRIM, UNMAP)
66 for each device.
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68 -d, --nodeps
69 Do not print holder devices or slaves. For example, lsblk --nodeps
70 /dev/sda prints information about the sda device only.
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72 -E, --dedup column
73 Use column as a de-duplication key to de-duplicate output tree. If
74 the key is not available for the device, or the device is a
75 partition and parental whole-disk device provides the same key than
76 the device is always printed.
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78 The usual use case is to de-duplicate output on system multi-path
79 devices, for example by -E WWN.
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81 -e, --exclude list
82 Exclude the devices specified by the comma-separated list of major
83 device numbers. Note that RAM disks (major=1) are excluded by
84 default if --all is not specified. The filter is applied to the
85 top-level devices only. This may be confusing for --list output
86 format where hierarchy of the devices is not obvious.
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88 -f, --fs
89 Output info about filesystems. This option is equivalent to -o
90 NAME,FSTYPE,FSVER,LABEL,UUID,FSAVAIL,FSUSE%,MOUNTPOINTS. The
91 authoritative information about filesystems and raids is provided
92 by the blkid(8) command.
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94 -I, --include list
95 Include devices specified by the comma-separated list of major
96 device numbers. The filter is applied to the top-level devices
97 only. This may be confusing for --list output format where
98 hierarchy of the devices is not obvious.
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100 -i, --ascii
101 Use ASCII characters for tree formatting.
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103 -J, --json
104 Use JSON output format. It’s strongly recommended to use --output
105 and also --tree if necessary.
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107 -l, --list
108 Produce output in the form of a list. The output does not provide
109 information about relationships between devices and since version
110 2.34 every device is printed only once if --pairs or --raw not
111 specified (the parsable outputs are maintained in backwardly
112 compatible way).
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114 -M, --merge
115 Group parents of sub-trees to provide more readable output for
116 RAIDs and Multi-path devices. The tree-like output is required.
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118 -m, --perms
119 Output info about device owner, group and mode. This option is
120 equivalent to -o NAME,SIZE,OWNER,GROUP,MODE.
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122 -N, --nvme
123 Output info about NVMe devices only.
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125 -v, --virtio
126 Output info about virtio devices only.
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128 -n, --noheadings
129 Do not print a header line.
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131 -o, --output list
132 Specify which output columns to print. Use --help to get a list of
133 all supported columns. The columns may affect tree-like output. The
134 default is to use tree for the column 'NAME' (see also --tree).
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136 The default list of columns may be extended if list is specified in
137 the format +list (e.g., lsblk -o +UUID).
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139 -O, --output-all
140 Output all available columns.
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142 -P, --pairs
143 Produce output in the form of key="value" pairs. The output lines
144 are still ordered by dependencies. All potentially unsafe value
145 characters are hex-escaped (\x<code>). See also option --shell.
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147 -p, --paths
148 Print full device paths.
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150 -r, --raw
151 Produce output in raw format. The output lines are still ordered by
152 dependencies. All potentially unsafe characters are hex-escaped
153 (\x<code>) in the NAME, KNAME, LABEL, PARTLABEL and MOUNTPOINT
154 columns.
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156 -S, --scsi
157 Output info about SCSI devices only. All partitions, slaves and
158 holder devices are ignored.
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160 -s, --inverse
161 Print dependencies in inverse order. If the --list output is
162 requested then the lines are still ordered by dependencies.
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164 -T, --tree[=column]
165 Force tree-like output format. If column is specified, then a tree
166 is printed in the column. The default is NAME column.
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168 -t, --topology
169 Output info about block-device topology. This option is equivalent
170 to
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172 -o
173 NAME,ALIGNMENT,MIN-IO,OPT-IO,PHY-SEC,LOG-SEC,ROTA,SCHED,RQ-SIZE,RA,WSAME.
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175 -h, --help
176 Display help text and exit.
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178 -V, --version
179 Print version and exit.
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181 -w, --width number
182 Specifies output width as a number of characters. The default is
183 the number of the terminal columns, and if not executed on a
184 terminal, then output width is not restricted at all by default.
185 This option also forces lsblk to assume that terminal control
186 characters and unsafe characters are not allowed. The expected
187 use-case is for example when lsblk is used by the watch(1) command.
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189 -x, --sort column
190 Sort output lines by column. This option enables --list output
191 format by default. It is possible to use the option --tree to force
192 tree-like output and than the tree branches are sorted by the
193 column.
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195 -y, --shell
196 The column name will be modified to contain only characters allowed
197 for shell variable identifiers, for example, MIN_IO and FSUSE_PCT
198 instead of MIN-IO and FSUSE%. This is usable, for example, with
199 --pairs. Note that this feature has been automatically enabled for
200 --pairs in version 2.37, but due to compatibility issues, now it’s
201 necessary to request this behavior by --shell.
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203 -z, --zoned
204 Print the zone related information for each device.
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206 --sysroot directory
207 Gather data for a Linux instance other than the instance from which
208 the lsblk command is issued. The specified directory is the system
209 root of the Linux instance to be inspected. The real device nodes
210 in the target directory can be replaced by text files with udev
211 attributes.
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214 0
215 success
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217 1
218 failure
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220 32
221 none of specified devices found
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223 64
224 some specified devices found, some not found
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227 LSBLK_DEBUG=all
228 enables lsblk debug output.
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230 LIBBLKID_DEBUG=all
231 enables libblkid debug output.
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233 LIBMOUNT_DEBUG=all
234 enables libmount debug output.
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236 LIBSMARTCOLS_DEBUG=all
237 enables libsmartcols debug output.
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239 LIBSMARTCOLS_DEBUG_PADDING=on
240 use visible padding characters.
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243 For partitions, some information (e.g., queue attributes) is inherited
244 from the parent device.
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246 The lsblk command needs to be able to look up each block device by
247 major:minor numbers, which is done by using /sys/dev/block. This sysfs
248 block directory appeared in kernel 2.6.27 (October 2008). In case of
249 problems with a new enough kernel, check that CONFIG_SYSFS was enabled
250 at the time of the kernel build.
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253 Milan Broz <gmazyland@gmail.com>, Karel Zak <kzak@redhat.com>
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256 ls(1), blkid(8), findmnt(8)
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259 For bug reports, use the issue tracker at
260 https://github.com/util-linux/util-linux/issues.
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263 The lsblk command is part of the util-linux package which can be
264 downloaded from Linux Kernel Archive
265 <https://www.kernel.org/pub/linux/utils/util-linux/>.
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269util-linux 2.39.2 2023-06-14 LSBLK(8)