blkid

Locate/print block device attributes (file system type, LABEL, UUID, etc.).

Description

In Linux, the blkid command can be used to query the file system type used on a device. blkid is primarily used to query information such as the file system type, LABEL, and UUID used by the system's block devices (including swap partitions). To use this command, the e2fsprogs package must be installed.

Syntax

blkid -L | -U
blkid [-c <file>] [-ghlLv] [-o <format>] [-s <tag>] [-t <token>] [-w <file>] [<dev> ...]
blkid -p [-s <tag>] [-O <offset>] [-S <size>] [-o <format>] <dev> ...
blkid -i [-s <tag>] [-o <format>] <dev> ...

Options

-c <file>   # Specify a cache file (default: /etc/blkid.tab, /dev/null = none)
-d          # Don't encode non-printing characters
-h          # Display help information
-g          # Garbage collect the blkid cache
-o <format> # Specify the output format
-k          # List all known filesystems/RAIDs and exit
-s <tag>    # Display specified information, defaults to all information
-t <token>  # Find device with a specific token (NAME=value pair)
-l          # Look up only the first device with the token specified by -t
-L <label>  # Convert LABEL to device name
-U <uuid>   # Convert UUID to device name
-v          # Display version information
-w <file>   # Write cache to a different file (/dev/null = no write)
<dev>       # Specify device(s) to probe (default: all devices)

Low-level probing options:
-p          # Low-level superblocks probing (bypass cache)
-i          # Gather information about I/O limits
-S <size>   # Overwrite device size
-O <offset> # Probe at the given offset
-u <list>   # Filter by "usage" (e.g., -u filesystem,raid)
-n <list>   # Filter by filesystem type (e.g., -n vfat,ext3)

Examples

1. List the types of all mounted file systems in the current system:

sudo blkid

2. Display the UUID of a specified device:

sudo blkid -s UUID /dev/sda5

3. Display the UUIDs of all devices:

sudo blkid -s UUID

4. Display the LABEL of a specified device:

sudo blkid -s LABEL /dev/sda5

5. Display the LABELs of all devices:

sudo blkid -s LABEL

6. Display the file system type of all devices:

sudo blkid -s TYPE

7. Display all devices:

sudo blkid -o device

8. View detailed information in list format:

sudo blkid -o list