— Command: install [--force-lba] [--stage2=os_stage2_file] stage1_file [d] dest_dev stage2_file [addr] [p] [config_file] [real_config_file]

This command is fairly complex, and you should not use this command unless you are familiar with GRUB. Use setup (see setup) instead.

In short, it will perform a full install presuming the Stage 2 or Stage 1.5¹ is in its final install location.

In slightly more detail, it will load stage1_file, validate that it is a GRUB Stage 1 of the right version number, install in it a blocklist for loading stage2_file as a Stage 2. If the option d is present, the Stage 1 will always look for the actual disk stage2_file was installed on, rather than using the booting drive. The Stage 2 will be loaded at address addr, which must be `0x8000' for a true Stage 2, and `0x2000' for a Stage 1.5. If addr is not present, GRUB will determine the address automatically. It then writes the completed Stage 1 to the first block of the device dest_dev. If the options p or config_file are present, then it reads the first block of stage2, modifies it with the values of the partition stage2_file was found on (for p) or places the string config_file into the area telling the stage2 where to look for a configuration file at boot time. Likewise, if real_config_file is present and stage2_file is a Stage 1.5, then the Stage 2 config_file is patched with the configuration file name real_config_file. This command preserves the DOS BPB (and for hard disks, the partition table) of the sector the Stage 1 is to be installed into.

Caution: Several buggy BIOSes don't pass a booting drive properly when booting from a hard disk drive. Therefore, you will unfortunately have to specify the option d, whether your Stage2 resides at the booting drive or not, if you have such a BIOS. We know these are defective in this way:

Fujitsu LifeBook 400 BIOS version 31J0103A

HP Vectra XU 6/200 BIOS version GG.06.11

Caution2: A number of BIOSes don't return a correct LBA support bitmap even if they do have the support. So GRUB provides a solution to ignore the wrong bitmap, that is, the option --force-lba. Don't use this option if you know that your BIOS doesn't have LBA support.

Caution3: You must specify the option --stage2 in the grub shell, if you cannot unmount the filesystem where your stage2 file resides. The argument should be the file name in your operating system.