Convert a Bootable USB Drive into an ISO Image Using GNOME Disks

GNOME Disks is a graphical utility pre‑installed on most GNOME‑based Linux desktops that can manage storage devices and create disk images. First, install the tool on your distribution:

Arch Linux: sudo pacman -S gnome-disk-utility Debian/Ubuntu: sudo apt install gnome-disk-utility RHEL/CentOS: sudo yum install gnome-disk-utility Fedora: sudo dnf install gnome-disk-utility openSUSE: sudo zypper in gnome-disk-utility After installation, insert the bootable USB drive and launch GNOME Disks from the Dash or menu.

Creating an ISO from a USB Partition

Select the USB device, then choose the partition that contains the ISO‑9660 filesystem. Click the gear icon (shown as two small gears) and pick "Create Partition Image" . In the dialog, give the image a name, choose a destination folder (e.g., ~/Documents), and click Start Creating . GNOME Disks will copy the selected partition to an .iso file.

Creating an Image of the Entire USB Disk

If you need a full‑disk backup, select the whole USB device in GNOME Disks, click the three‑line menu in the upper‑right corner, and choose "Create Disk Image" . Specify a name and location; the image will be saved as an .img file. You may later convert this .img to an ISO with a suitable conversion tool.

Verifying the Created ISO

When the creation process finishes, locate the saved ISO file and test it by booting a virtual machine (e.g., VirtualBox). The author confirmed that the generated ISO boots successfully.

These steps provide a quick way to recover an ISO image from a lost source by simply using the existing bootable USB drive.