# LSBLK - list block devices - man - [phpMan]

> **TLDR:** List information about devices.
>
- List all storage devices in a tree-like format:
  `lsblk`
- Also list empty devices:
  `lsblk {{-a|--all}}`
- Print the SIZE column in bytes rather than in a human-readable format:
  `lsblk {{-b|--bytes}}`
- Output info about filesystems:
  `lsblk {{-f|--fs}}`
- Use ASCII characters for tree formatting:
  `lsblk {{-i|--ascii}}`
- Output info about block-device topology:
  `lsblk {{-t|--topology}}`
- Exclude the devices specified by the comma-separated list of major device numbers:
  `lsblk {{-e|--exclude}} {{1,7,...}}`
- Add extra information to the output using a comma-separated list of columns (omit the `+` sign to only display the specified columns):
  `lsblk {{-o|--output}} +{{NAME,ROTA,SERIAL,MODEL,TRAN,TYPE,SIZE,FSTYPE,MOUNTPOINT,...}}`

*Source: tldr-pages*

---

[_LSBLK_(8)](https://www.chedong.com/phpMan.php/man/LSBLK/8/markdown)                                System Administration                               [_LSBLK_(8)](https://www.chedong.com/phpMan.php/man/LSBLK/8/markdown)

## 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, then it tries to read LABELs, UUIDs and filesystem
       types from the block device. In this case root permissions are necessary.

       By default, the command prints all block devices (except RAM disks) in a tree-like format.
       The same device can be repeated in the tree if it relates to other devices. The **--merge**
       option is recommended for more complicated setups to gather groups of devices and describe
       complex N:M relationships.

       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_ and **--list**
       in environments where a stable output is required.

       Use **lsblk --help **to get a list of all available columns.

       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.

       The relationship between block devices and filesystems is not always one-to-one. The
       filesystem may use more block devices, or the same filesystem may be accessible by more
       paths. This is the reason why **lsblk **provides MOUNTPOINT and MOUNTPOINTS (pl.) columns. The
       column MOUNTPOINT displays only one mount point (usually the last mounted instance of the
       filesystem), and the column MOUNTPOINTS displays by multi-line cell all mount points
       associated with the device.

## OPTIONS
### -A --noempty
           Don’t print empty devices.

### -a --all
           Disable all built-in filters and list all empty devices and RAM disk devices too.

### -b --bytes
           Print the sizes in bytes rather than in a human-readable format.

           By default, the unit, sizes are expressed in, is byte, and unit prefixes are in power of
           2^10 (1024). Abbreviations of symbols are exhibited truncated in order to reach a better
           readability, by exhibiting alone the first letter of them; examples: "1 KiB" and "1 MiB"
           are respectively exhibited as "1 K" and "1 M", then omitting on purpose the mention "iB",
           which is part of these abbreviations.

### -D --discard
           Print information about the discarding capabilities (TRIM, UNMAP) 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 --dedup _
           Use _column_ as a de-duplication key to de-duplicate output tree. If the key is not
           available for the device, or the device is a partition and parental whole-disk device
           provides the same key than the device is always printed.

           The usual use case is to de-duplicate output on system multi-path devices, for example by
           **-E WWN**.

### -e --exclude _
           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 not specified. The filter is
           applied to the top-level devices only. This may 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,FSVER,LABEL,UUID,FSAVAIL,FSUSE%,MOUNTPOINTS**. The authoritative information
           about filesystems and raids is provided by the [**blkid**(8)](https://www.chedong.com/phpMan.php/man/blkid/8/markdown) command.

### -I --include _
           Include devices specified by the comma-separated _list_ of major device numbers. The filter
           is applied to the top-level devices only. This may 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. It’s strongly recommended to use **--output **and also **--tree **if
           necessary.

### -l --list
           Produce output in the form of a list. The output does not provide information about
           relationships between devices and since version 2.34 every device is printed only once if
           **--pairs **or **--raw **not specified (the parsable outputs are maintained in backwardly
           compatible way).

### -M --merge
           Group parents of sub-trees to provide more readable output for RAIDs and Multi-path
           devices. The tree-like output is required.

### -m --perms
           Output info about device owner, group and mode. This option is equivalent to **-o**
           **NAME,SIZE,OWNER,GROUP,MODE**.

### -N --nvme
           Output info about NVMe devices only.

### -v --virtio
           Output info about virtio devices only.

### -n --noheadings
           Do not print a header line.

### -o --output _
           Specify which output columns to print. Use **--help **to get a list of all supported columns.
           The columns may affect tree-like output. The default is to use tree for the column 'NAME'
           (see also **--tree**).

           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. The output lines are still ordered by
           dependencies. All potentially unsafe value characters are hex-escaped (\x<code>). See
           also option **--shell**.

### -p --paths
           Print full device paths.

### -r --raw
           Produce output in raw format. The output lines are still ordered by dependencies. 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 --tree
           Force tree-like output format. If _column_ is specified, then a tree is printed in the
           column. The default is NAME column.

### -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**.

### -h --help
           Display help text and exit.

### -V --version
           Print version and exit.

### -w --width _
           Specifies output width as a number of characters. The default is the number of the
           terminal columns, and if not executed on a terminal, then output width is not restricted
           at all by default. This option also forces **lsblk **to assume that terminal control
           characters and unsafe characters are not allowed. The expected use-case is for example
           when **lsblk **is used by the [**watch**(1)](https://www.chedong.com/phpMan.php/man/watch/1/markdown) command.

### -x --sort _
           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_.

### -y --shell
           The column name will be modified to contain only characters allowed for shell variable
           identifiers, for example, MIN_IO and FSUSE_PCT instead of MIN-IO and FSUSE%. This is
           usable, for example, with **--pairs**. Note that this feature has been automatically enabled
           for **--pairs **in version 2.37, but due to compatibility issues, now it’s necessary to
           request this behavior by **--shell**.

### -z --zoned
           Print the zone related information for each device.

       **--sysroot _**directory_
           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.
           The real device nodes in the target directory can be replaced by text files with udev
           attributes.

## EXIT STATUS
       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.

## 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.

## AUTHORS
       Milan Broz <<gmazyland@gmail.com>>, Karel Zak <<kzak@redhat.com>>

## SEE ALSO
       [**ls**(1)](https://www.chedong.com/phpMan.php/man/ls/1/markdown), [**blkid**(8)](https://www.chedong.com/phpMan.php/man/blkid/8/markdown), [**findmnt**(8)](https://www.chedong.com/phpMan.php/man/findmnt/8/markdown)

## REPORTING BUGS
       For bug reports, use the issue tracker at <https://github.com/util-linux/util-linux/issues>.

## AVAILABILITY
       The **lsblk **command is part of the util-linux package which can be downloaded from Linux Kernel
       Archive <<https://www.kernel.org/pub/linux/utils/util-linux/>>.

util-linux 2.39.3                            2023-12-01                                     [_LSBLK_(8)](https://www.chedong.com/phpMan.php/man/LSBLK/8/markdown)
