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

Stop wondering where your cloud block storage went

🧩 The Challenge

You finally bump up that AWS EBS volume or a thin-provisioned LUN, but the filesystem still thinks the old size is the limit. It’s infuriating to pay for extra capacity that your kernel refuses to acknowledge.

💡 The Fix

Trigger a filesystem resize operation while the volume is mounted to bridge that gap. You won’t even need to take your service down for a reboot to get that extra space online.

resize2fs /dev/mapper/vg00-lv_root

⚙️ Why It Works

Expanding the physical block device is only half the battle; this command tells the filesystem driver to stretch its data structures to fill the newly available blocks on the partition.

🚀 Pro-Tip: Run lsblk first to confirm the device actually shows the new size before you try to resize the filesystem, otherwise you’re just yelling at the wind.

Linux Tips & Tricks | © ngelinux.com | 8/31/2026