To know how much disk space is occupied on each disk you might run df -h in the terminal. The -h means --human-readable :)
Example output:
Filesystem Size Used Avail Use% Mounted on
dev 16G 0 16G 0% /dev
run 16G 2.0M 16G 1% /run
/dev/nvme0n1p2 59G 37G 20G 66% /
tmpfs 16G 202M 16G 2% /dev/shm
tmpfs 16G 41M 16G 1% /tmp
/dev/nvme0n1p3 175G 91G 76G 55% /home
tmpfs 3.2G 88K 3.2G 1% /run/user/1000
In my example, I see my Linux root is occupied up to 66% and only 20G is available. Now I need to see what takes the most space on the root disk. I have a couple of options to check that out. Graphical or TUI :) In this article, we explore two of the best options.
Filelight - Graphical disk-usage information
Since I want to check out the result on my root directory I have to run Filelight with root privileges.
sudo filelight
In the opened window I go for the Scan Root Folder option.
In the output, I see Docker has occupied a large amount of space on my disk. About 17G!
NCDU - Disk usage analyzer with an ncurses interface
For those who work with a Linux server via ssh and do not have a graphical interface an application with TUI; a terminal user interface; can be very helpful. After installing ncdu just run it on whatever path you need. In my case, I run it on my root directory.
sudo ncdu /
You can easily navigate to each directory using arrow keys.
Now that I found out Docker has occupied a large amount of space on my root disk. I have to transfer its file to a new location without breaking it. In my upcoming article, I will explain how to do it.