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BLKID(8) System Administration BLKID(8)

NAME
blkid - locate/print block device attributes

SYNOPSIS
blkid -L label | -U uuid

blkid [-dghlv] [-c file] [-w file] [-o format]
[-s tag] [-t NAME=value] [device ...]

blkid -p [-O offset] [-S size] [-o format] [-s tag]
[-n list] [-u list] device ...

blkid -i [-o format] [-s tag] device ...

DESCRIPTION
The blkid program is the command-line interface to working with the libblkid(3) library. It can determine the type of content (e.g. filesystem or swap) that a block
device holds, and also attributes (tokens, NAME=value pairs) from the content metadata (e.g. LABEL or UUID fields).

blkid has two main forms of operation: either searching for a device with a specific NAME=value pair, or displaying NAME=value pairs for one or more specified
devices.

OPTIONS
The size and offset arguments may be followed by binary (2^N) suffixes KiB, MiB, GiB, TiB, PiB and EiB (the "iB" is optional, e.g. "K" has the same meaning as "KiB")
or decimal (10^N) suffixes KB, MB, GB, PB and EB.

-c cachefile
Read from cachefile instead of reading from the default cache file /etc/blkid.tab. If you want to start with a clean cache (i.e. don't report devices previ‐
ously scanned but not necessarily available at this time), specify /dev/null.

-d Don't encode non-printing characters. The non-printing characters are encoded by ^ and M- notation by default. Note that -o udev output format uses a diffrent
encoding and this encoding cannot be disabled.

-g Perform a garbage collection pass on the blkid cache to remove devices which no longer exist.

-h Display a usage message and exit.

-i Display I/O Limits (aka I/O topology) information. The 'export' output format is automatically enabled. This option can be used together with the -p option.

-l Look up only one device that matches the search parameter specified with -t.

-k List all known filesystems and RAIDs and exit.

-t option. If there are multiple devices that match the specified search parameter, then the device with the highest priority is returned, and/or the first
device found at a given priority. Device types in order of decreasing priority are Device Mapper, EVMS, LVM, MD, and finally regular block devices. If this
option is not specified, blkid will print all of the devices that match the search parameter.

-L label
Look up the device that uses this label (equal to: -l -o device -t LABEL=<label>). This lookup method is able to reliably use /dev/disk/by-label udev symâ€