24.1 Invoking grub-install

The program grub-install generates a GRUB core image using grub-mkimage and installs it on your system. You must specify the device name on which you want to install GRUB, like this:

grub-install install_device

The device name install_device is an OS device name or a GRUB device name.

grub-install accepts the following options:

--help

Print a summary of the command-line options and exit.

--version

Print the version number of GRUB and exit.

--boot-directory=dir

Install GRUB images under the directory dir/grub/ This option is useful when you want to install GRUB into a separate partition or a removable disk. If this option is not specified then it defaults to /boot, so

grub-install /dev/sda

is equivalent to

grub-install --boot-directory=/boot/ /dev/sda

Here is an example in which you have a separate boot partition which is mounted on /mnt/boot:

grub-install --boot-directory=/mnt/boot /dev/sdb

--recheck

Recheck the device map, even if /boot/grub/device.map already exists. You should use this option whenever you add/remove a disk into/from your computer.

--no-rs-codes

By default on x86 BIOS systems, grub-install will use some extra space in the bootloader embedding area for Reed-Solomon error-correcting codes. This enables GRUB to still boot successfully if some blocks are corrupted. The exact amount of protection offered is dependent on available space in the embedding area. R sectors of redundancy can tolerate up to R/2 corrupted sectors. This redundancy may be cumbersome if attempting to cryptographically validate the contents of the bootloader embedding area, or in more modern systems with GPT-style partition tables (see BIOS installation) where GRUB does not reside in any unpartitioned space outside of the MBR. Disable the Reed-Solomon codes with this option.