How do I find total size of hard drive use command line

Question

I've try to find out the total size of my hard drive use df -h but it print size of each partition and require "sudo".

Is there any way to get total size of my hard drive use command line and not require root permission?

Answer 1

A hacky way is to bypass the need for sudo by reading out the system log with:

dmesg | grep blocks

Please note that this might not be ideal, so your mileage may vary...

Answer 2

I'm not at my Linux box right now, but you could try:

hdparm -I /dev/sda

or

fdisk -l

which will also probably require a sudo.

I haven't seen anywhere that df requires root. That's odd.

Answer 3

If you want to use that information in a script for example, using

sudo blockdev --getsz /dev/sda

might be easier than fdisk or hdparm as it only gives you the relevant information (just multiply by 512). However, it will also require sudo.

You could of course change the configuration of sudo such that it allows to execute this specific command without asking for the password (I guess blockdev --getsz is pretty safe even when executed by a normal non-privileged user).

This would be done by adding the following line to /etc/sudoers:

ALL ALL= NOPASSWD:/sbin/blockdev --getsz /dev/*

When you edit this file, be sure to use the command sudo visudo and not your usual editor. Otherwise it is very easy to make a syntax error, which would result in not being able to use sudo anymore (you would have to reboot into rescue mode to fix this).

Answer 4

You either have a bad install or an absurdly paranoid sysadmin. I've never heard of df requiring root privileges before. And I've worked with quite a few different flavors of unix/unix-like operating systems.

Anyhow, this will give you the total size of all disk partitions (first df column is /dev/hd... or /dev/sd...) in blocks (kB):

df | grep '^/dev/[hs]d' | awk '{s+=$2} END {print s}'

or in GB:

df | grep '^/dev/[hs]d' | awk '{s+=$2} END {print s/1048576}'

Answer 5

cat /sys/block/sda/size

But the size is in block-based unit
I found this answer here.
Other solutions here.

Or you can try udisks

udisks --show-info /dev/sda | egrep "^[[:space:]]*size" | awk '{print $2}'