sudo apt install ncdu ncdu --exclude /mnt
Here is what the above code is Doing:
1. Install ncdu
2. Run ncdu with the –exclude /mnt option
The –exclude /mnt option tells ncdu to ignore the /mnt directory.
The /mnt directory is where you mount external drives.
If you don’t exclude the /mnt directory, ncdu will scan the external drive.
This can take a long time.