grub-probe

Get GRUB filesystem module for a path

$ sudo grub-probe -t fs /boot/grub

$ sudo grub-probe -t device /boot/grub

$ sudo grub-probe -t drive /dev/sdX -d

$ sudo grub-probe -t fs_uuid /boot/grub

$ sudo grub-probe -t fs_label /boot/grub

$ sudo grub-probe -t msdos_parttype /dev/sdX

$ sudo grub-probe -t drive /boot/grub -m [path/to/custom_device.map]

grub-probe [options] -t target path|device

grub-probe extracts device and filesystem information in GRUB's naming format. It is primarily used internally by GRUB tools but is useful for debugging boot configuration.
Target types include fs (filesystem type), device (Linux device path), drive (GRUB drive name like hd0), fs_uuid (filesystem UUID), fs_label (filesystem label), and partmap (partition map type).
This tool bridges Linux device names to GRUB's naming conventions, which is essential for generating correct boot configurations.

-t, --target TARGET

Information to probe: fs, device, drive, fsuuid, fslabel, partmap, msdos_parttype

Treat argument as device, not path

Use custom device map file

Enable verbose output

Requires root privileges for most operations. Device mapping can change between boots, especially with removable media. GRUB drive naming may differ from Linux device names.

grub-probe is part of GRUB 2's toolset, providing the device detection logic used by grub-install and grub-mkconfig. It replaced simpler detection methods used in GRUB Legacy.

grub-install(8), grub-mkconfig(8), blkid(8)