1.3 Differences from previous versions

GRUB 2 is a rewrite of GRUB (see History), although it shares many characteristics with the previous version, now known as GRUB Legacy. Users of GRUB Legacy may need some guidance to find their way around this new version.

• The configuration file has a new name (grub.cfg rather than menu.lst or grub.conf), new syntax (see Configuration) and many new commands (see Commands). Configuration cannot be copied over directly, although most GRUB Legacy users should not find the syntax too surprising.
• grub.cfg is typically automatically generated by grub-mkconfig (see Simple configuration). This makes it easier to handle versioned kernel upgrades.
• Partition numbers in GRUB device names now start at 1, not 0 (see Naming convention).
• The configuration file is now written in something closer to a full scripting language: variables, conditionals, and loops are available.
• A small amount of persistent storage is available across reboots, using the save_env and load_env commands in GRUB and the grub-editenv utility. This is not available in all configurations (see Environment block).
• GRUB 2 has more reliable ways to find its own files and those of target kernels on multiple-disk systems, and has commands (see search) to find devices using file system labels or Universally Unique Identifiers (UUIDs).
• GRUB 2 is available for several other types of system in addition to the PC BIOS systems supported by GRUB Legacy: PC EFI, PC coreboot, PowerPC, SPARC, and MIPS Lemote Yeeloong are all supported.
• Many more file systems are supported, including but not limited to ext4, HFS+, and NTFS.
• GRUB 2 can read files directly from LVM and RAID devices.
• A graphical terminal and a graphical menu system are available.
• GRUB 2’s interface can be translated, including menu entry names.
• The image files (see Images) that make up GRUB have been reorganised; Stage 1, Stage 1.5, and Stage 2 are no more.
• GRUB 2 puts many facilities in dynamically loaded modules, allowing the core image to be smaller, and allowing the core image to be built in more flexible ways.