How do I find the remaining space on an External Drive?

Question

Through terminal on Linux, what exactly would I type to find External HDDs and their remaining storage space?

Answer 1

Linux doesn't differentiate between external and internal drives in any obvious way* – so you'll need to get a bit sneaky to get what you want.

Let's start with the most common scenario – you're running a desktop Linux install, and the drive was mounted for you by some helper program – in which case your drive might have a mount point that looks like /media/username/disklabel/.

If you mounted it manually, you'd know the location – and generally this would be under /media/ or, if you're doing it old-school, /mnt/.

So, if you start with:

df -h

… which would give you Disk Free, Human readable, and filtered the output to any entry whose Mounted on column pointed at an obvious location for external drives, like /media/, you have a good chance of finding the amount of disk free for just your external drives.

_{* On some older kernels, with the older ATA driver, PATA hard drives were denoted by /dev/hdX and most other drives were treated as SCSI drives with a /dev/sdX designation. On a system with no SCSI or SATA drives, there was a good chance external USB drives would be under /dev/sdX. Modern kernels however treat everything as a SCSI drive.}