16.4.2. Using the blkid Command
The blkid command allows you to display information about available block devices. To do so, type the following at a shell prompt as root:
blkid
For each listed block device, the blkid command displays available attributes such as its universally unique identifier (UUID), file system type (TYPE), or volume label (LABEL). For example:
~]# blkid
/dev/vda1: UUID="4ea24c68-ab10-47d4-8a6b-b8d3a002acba" TYPE="ext4"
/dev/vda2: UUID="iJ9YwJ-leFf-A1zb-VVaK-H9t1-raLW-HoqlUG" TYPE="LVM2_member"
/dev/mapper/vg_fedora-lv_swap: UUID="d6d755bc-3e3e-4e8f-9bb5-a5e7f4d86ffd" TYPE="swap"
/dev/mapper/vg_fedora-lv_root: LABEL="_Fedora-17-x86_6" UUID="77ba9149-751a-48e0-974f-ad94911734b9" TYPE="ext4"
By default, the lsblk command lists all available block devices. To display information about a particular device only, specify the device name on the command line:
blkid device_name
For instance, to display information about /dev/vda1, type:
~]# blkid /dev/vda1
/dev/vda1: UUID="4ea24c68-ab10-47d4-8a6b-b8d3a002acba" TYPE="ext4"
You can also use the above command with the -p and -o udev command line options to obtain more detailed information. Note that root privileges are required to run this command:
blkid -po udev device_name
For example:
~]# blkid -po udev /dev/vda1
ID_FS_UUID=4ea24c68-ab10-47d4-8a6b-b8d3a002acba
ID_FS_UUID_ENC=4ea24c68-ab10-47d4-8a6b-b8d3a002acba
ID_FS_VERSION=1.0
ID_FS_TYPE=ext4
ID_FS_USAGE=filesystem
ID_PART_ENTRY_SCHEME=dos
ID_PART_ENTRY_TYPE=0x83
ID_PART_ENTRY_FLAGS=0x80
ID_PART_ENTRY_NUMBER=1
ID_PART_ENTRY_OFFSET=2048
ID_PART_ENTRY_SIZE=1024000
ID_PART_ENTRY_DISK=252:0
For a complete list of available command line options, refer to the blkid(8) manual page.
