How to show disk information in Linux

Showing disk information in Linux helps you match each disk to its partitions, filesystem, and mount points before you mount new storage, resize a volume, replace a failing disk, or investigate where space is being used.

Linux exposes storage as block devices under /dev. lsblk builds a readable device tree from sysfs and udev data, blkid reads filesystem metadata such as UUID and PARTUUID from the selected device, and df reports how much space the mounted filesystems are actually using.

The lsblk manual warns that the default columns can change, so explicit column lists keep the output predictable. The examples below use a simple sda layout with an EFI system partition, but other hosts may use paths such as /dev/vda or /dev/nvme0n1, and blkid should be run with sudo when exact on-disk identifiers matter.

1. List the block devices with explicit lsblk columns so the disk, partition, filesystem, and mount-point layout is easy to read.

   $ lsblk -o NAME,SIZE,TYPE,FSTYPE,MOUNTPOINTS
   NAME     SIZE TYPE FSTYPE MOUNTPOINTS
   ##### snipped #####
   sda       64G disk
   ├─sda1     1G part vfat   /boot/efi
   └─sda2    63G part ext4   /
   sdb      200G disk

   Explicit columns keep the output predictable even when the default lsblk view changes, and MOUNTPOINTS shows every active mount path for a device.

2. Show only whole-disk entries when you need the device path, model, transport, or size before drilling into partitions.

   $ lsblk -d -o PATH,MODEL,TRAN,SIZE,TYPE
   PATH     MODEL                TRAN SIZE TYPE
   /dev/sda VMware Virtual disk sata  64G disk
   /dev/sdb VMware Virtual disk sata 200G disk

   Virtual machines, cloud instances, and USB bridges can show generic or blank MODEL and TRAN fields. Add SERIAL to the column list when the disk serial number matters and the hardware exposes it.

3. Inspect one disk directly when you want the exact device path and the partition nodes that belong to it.

   $ lsblk /dev/sda -o PATH,SIZE,TYPE,FSTYPE,MOUNTPOINTS
   PATH      SIZE TYPE FSTYPE MOUNTPOINTS
   /dev/sda   64G disk
   /dev/sda1   1G part vfat   /boot/efi
   /dev/sda2  63G part ext4   /

   Replace /dev/sda with the disk from the earlier inventory, such as /dev/sdb, /dev/vda, or /dev/nvme0n1. The partition paths from this output are the ones you pass to tools such as mount, fsck, or blkid.

4. Read the filesystem metadata from the partitions when you need their UUID or PARTUUID values.

   $ sudo blkid /dev/sda1 /dev/sda2
   /dev/sda1: UUID="058E-72AC" BLOCK_SIZE="512" TYPE="vfat" PARTUUID="b21e1324-43fb-436f-b519-8a75581b2a1b"
   /dev/sda2: UUID="c7f70fb1-ad04-47c0-8aa2-873cbef19d05" BLOCK_SIZE="4096" TYPE="ext4" PARTUUID="ef3ea15d-b212-4c1c-b1df-09f77e3fb2b2"

   UUID identifies the filesystem, while PARTUUID identifies the partition entry itself. The blkid manual notes that non-root users can receive cached unverified data, so use sudo when exact metadata matters.

5. Check mounted filesystem usage for the active mounts on that disk.

   $ df -hT / /boot/efi
   Filesystem     Type  Size  Used Avail Use% Mounted on
   /dev/sda2      ext4   62G   11G   48G  19% /
   /dev/sda1      vfat  1.1G  6.4M  1.1G   1% /boot/efi

   df reports only mounted filesystems. Use lsblk or blkid when you also need information about unmounted partitions.