Disk & Filesystem Management (Du/Df/Lsblk/Fstrim)

Stop ignoring the mount points hiding under your nose

🧩 The Challenge

Ever spent an hour running du -sh across your root partition only to find the math doesn’t add up? It’s usually because you’ve got a mount point obscuring a folder full of ancient logs or a stray backup that’s eating your disk alive.

💡 The Fix

Use findmnt to verify what’s actually sitting on top of your directories instead of guessing blindly. It’s a cleaner way to see your filesystem tree without staring at a wall of df output.

findmnt --real --submounts --output TARGET,SOURCE,FSTYPE,SIZE,USED,AVAIL,USE%

⚙️ Why It Works

This command ignores your swap and pseudo-filesystems, giving you a flat, readable view of where your storage is actually being consumed across active mounts.

🚀 Pro-Tip: Pipe it into column -t if your output is getting messy and hard to read.

Linux Tips & Tricks | © ngelinux.com | 10/16/2026