1LSBLK(8)                     System Administration                    LSBLK(8)
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NAME

6       lsblk - list block devices
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SYNOPSIS

9       lsblk [options] [device...]
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DESCRIPTION

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 com‐
15       piled without udev support than it tries  to  read  LABELs,  UUIDs  and
16       filesystem  types  from the block device. In this case root permissions
17       are necessary.
18
19       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
23       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
29       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.
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OPTIONS

35       -a, --all
36              Also list empty devices and RAM disk devices.
37
38       -b, --bytes
39              Print  the  SIZE column in bytes rather than in a human-readable
40              format.
41
42       -D, --discard
43              Print  information  about  the  discarding  capabilities  (TRIM,
44              UNMAP) for each device.
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46       -d, --nodeps
47              Do  not  print  holder  devices  or  slaves.  For example, lsblk
48              --nodeps /dev/sda prints information about the sda device only.
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50       -E, --dedup column
51              Use column as a de-duplication key to de-duplicate output  tree.
52              If  the  key is not available for the device, or the device is a
53              partition and parental whole-disk device provides the  same  key
54              than the device is always printed.
55
56              The  usual  use  case is to de-duplicate output on system multi-
57              path devices, for example by -E WWN.
58
59       -e, --exclude list
60              Exclude the devices specified by  the  comma-separated  list  of
61              major  device  numbers.   Note  that  RAM  disks  (major=1)  are
62              excluded by default if --all is not specified.   The  filter  is
63              applied to the top-level devices only. This may be confusing for
64              --list output format where hierarchy of the devices is not obvi‐
65              ous.
66
67       -f, --fs
68              Output  info  about  filesystems.   This option is equivalent to
69              -o NAME,FSTYPE,LABEL,UUID,MOUNTPOINT.  The authoritative  infor‐
70              mation  about  filesystems and raids is provided by the blkid(8)
71              command.
72
73       -h, --help
74              Display help text and exit.
75
76       -I, --include list
77              Include devices specified by the comma-separated list  of  major
78              device  numbers.  The filter is applied to the top-level devices
79              only. This may be confusing for --list output format where hier‐
80              archy of the devices is not obvious.
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82       -i, --ascii
83              Use ASCII characters for tree formatting.
84
85       -J, --json
86              Use JSON output format.  It's strongly recommended to use --out‐
87              put and also --tree if necessary.
88
89       -l, --list
90              Produce output in the form of a list. The output does  not  pro‐
91              vide  information  about relationships between devices and since
92              version 2.34 every device is printed only once.
93
94       -M, --merge
95              Group parents of sub-trees to provide more readable  output  for
96              RAIDs and Multi-path devices. The tree-like output is required.
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98       -m, --perms
99              Output  info about device owner, group and mode.  This option is
100              equivalent to -o NAME,SIZE,OWNER,GROUP,MODE.
101
102       -n, --noheadings
103              Do not print a header line.
104
105       -o, --output list
106              Specify which output columns to print.  Use --help to get a list
107              of all supported columns.  The columns may affect tree-like out‐
108              put.  The default is to use tree for the column 'NAME' (see also
109              --tree).
110
111              The default list of columns may be extended if list is specified
112              in the format +list (e.g. lsblk -o +UUID).
113
114       -O, --output-all
115              Output all available columns.
116
117       -P, --pairs
118              Produce output in the form of  key="value"  pairs.   All  poten‐
119              tially unsafe characters are hex-escaped (\x<code>).
120
121       -p, --paths
122              Print full device paths.
123
124       -r, --raw
125              Produce output in raw format.  All potentially unsafe characters
126              are hex-escaped (\x<code>) in the NAME, KNAME, LABEL,  PARTLABEL
127              and MOUNTPOINT columns.
128
129       -S, --scsi
130              Output info about SCSI devices only.  All partitions, slaves and
131              holder devices are ignored.
132
133       -s, --inverse
134              Print dependencies in inverse order. If  the  --list  output  is
135              requested then the lines are still ordered by dependencies.
136
137       -T, --tree[=column]
138              Force  tree-like  output format.  If column is specified, then a
139              tree is printed in the column.  The default is NAME column.
140
141       -t, --topology
142              Output info about block-device topology.  This option is equiva‐
143              lent       to       -o NAME,ALIGNMENT,MIN-IO,OPT-IO,PHY-SEC,LOG-
144              SEC,ROTA,SCHED,RQ-SIZE,RA,WSAME.
145
146       -V, --version
147              Display version information and exit.
148
149       -x, --sort column
150              Sort output lines by column. This option enables  --list  output
151              format  by  default.  It is possible to use the option --tree to
152              force tree-like output and than the tree branches are sorted  by
153              the column.
154
155       -z, --zoned
156              Print the zone model for each device.
157
158        --sysroot directory
159              Gather  data  for  a Linux instance other than the instance from
160              which the lsblk command is issued.  The specified  directory  is
161              the  system  root  of  the Linux instance to be inspected.  This
162              option is designed for the testing purpose.
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NOTES

166       For partitions, some information (e.g. queue attributes)  is  inherited
167       from the parent device.
168
169       The  lsblk  command  needs  to  be able to look up each block device by
170       major:minor numbers, which is done by using /sys/dev/block.  This sysfs
171       block  directory  appeared in kernel 2.6.27 (October 2008).  In case of
172       problems with a new enough kernel, check that CONFIG_SYSFS was  enabled
173       at the time of the kernel build.
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RETURN CODES

177       0      success
178
179       1      failure
180
181       32     none of specified devices found
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183       64     some specified devices found, some not found
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AUTHORS

187       Milan Broz <mbroz@redhat.com>
188       Karel Zak <kzak@redhat.com>
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ENVIRONMENT

191       LSBLK_DEBUG=all
192              enables lsblk debug output.
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194       LIBBLKID_DEBUG=all
195              enables libblkid debug output.
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197       LIBMOUNT_DEBUG=all
198              enables libmount debug output.
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200       LIBSMARTCOLS_DEBUG=all
201              enables libsmartcols debug output.
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203       LIBSMARTCOLS_DEBUG_PADDING=on
204              use  visible  padding  characters.  Requires  enabled  LIBSMART‐
205              COLS_DEBUG.
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SEE ALSO

208       ls(1), blkid(8), findmnt(8)
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AVAILABILITY

211       The lsblk command is part of the util-linux package  and  is  available
212       from https://www.kernel.org/pub/linux/utils/util-linux/.
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216util-linux                       February 2013                        LSBLK(8)
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