SYSLinux vs GRUB
Both are disk-based boot loaders, and perform similar functions. They are the first software loaded from disk to run.
What is SysLinux
- SysLinux has pretty much taken a more minimalist approach, whereas GRUB was much more extensive.
- GRUB also supports different filesystems through the use of a secondary loader.
- If memory serves, syslinux supports a few formats and doesn’t require a secondary boot loader.
The naming of boot loaders shall be clarified:
- Name with all letters capitalized refers to the boot loader (e.g. GRUB, SYSLINUX)
- Name with initial letter capitalized refers to the project name or, several or all variants of the boot loader family (e.g. Syslinux)
- In particular, ‘Syslinux’ is a collection of boot loaders that includes ‘SYSLINUX’, ‘ISOLINUX’, ‘EXTLINUX’ and ‘PXELINUX’.
2005: ISOLINUX is choosen for Ubuntu CD Boot Loader, instead of GRUB.
GRUB has been suggested before as a possible replacement boot loader, but this approach was tried in the Warty live CD where we observed significant regressions in bootability versus the ISOLINUX-using install CD.
2006: Portable GfxBoot, has been added; This supports information quoted in 2010.
In Dapper, we added gfxboot to our amd64 and i386 CD images, providing a friendly graphical boot menu as the first thing users see when booting Ubuntu CD images on those architecture.
2009: SYSLINUX It is still used for booting Ubuntu CD.
Ubuntu live CDs still boot using SYSLINUX, which does not include support for starting the kernel in graphics mode. This means that live CDs display a graphical boot menu, then switch back to text mode to start the kernel, and will then normally switch back to graphics mode later.
2010: ISOLINUX has been used, but GRUB 2 is needed for UEFI support.
Current Ubuntu CDs use ISOLINUX, with the gfxboot extensions from SuSE implementing graphical menus.
This has proven to be rather difficult to maintain, with only one person in Ubuntu who understands the theming code involved.
- ISOLINUX was preferred due to GRUB had regressions back then (2005)
- ISOLINUX was still preferred despit1e lack of support for starting the kernel in graphics mode that cause flickering during boot transition (2009)
- ISOLINUX has been used with gfxboot to provide graphical menu, which was not implemented or not possible with GRUB back then (2010)
- GRUB has been added later to boot with UEFI support since Maverick (post-2010)