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LSBLK(8) - Linux man page online | Administration and privileged commands

List block devices.

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February 2013
LSBLK(8) System Administration LSBLK(8)

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 neces‐ sary. 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 set‐ tle before lsblk to synchronize with udev.

OPTIONS

-a, --all Also list empty devices. (By default they are skipped.) -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. The filter is applied to the top-level devices only. -f, --fs Output info about filesystems. This option is equivalent to -o NAME,FSTYPE,LABEL,UUID,MOUNTPOINT. The authoritative information about filesys‐ tems 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. -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.

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 CON‐ FIG_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

AUTHORS

Milan Broz <@redhat.com> Karel Zak <@redhat.com>

ENVIRONMENT

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.

SEE ALSO

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

AVAILABILITY

The lsblk command is part of the util-linux package and is available from https://www.ker‐ nel.org/pub/linux/utils/util-linux/.
util-linux February 2013 LSBLK(8)
This manual Reference Other manuals
lsblk(8) referred by blkdeactivate(8) | blkid(8) | cfdisk(8) | findfs(8) | fstab(5) | iosnoop-perf(8) | mount(2)
refer to blkid(8) | findmnt(8) | ls(1)
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