#Add ubuntu to win 10 boot loader windows#

#Add ubuntu to win 10 boot loader windows#

This functionality can be configured from Linux with the efibootmgr tool or from Windows with bcdedit or the third-party EasyUEFI. The critical difference is that the boot manager launches the kernel by using EFI system calls, as if the kernel were a boot loader - which it technically is.Īnother issue to keep in mind is that the EFI spec includes a minimal boot manager, which is built into the firmware, not stored on disk. Thus, a boot manager (like rEFInd or gummiboot/systemd-boot) can start looking a lot like a combination boot manager/boot loader, in that the boot manager launches the kernel. Since version 3.3.0, the Linux kernel has included a feature, called the EFI stub loader, that turns it into its own boot loader.My understanding is that it's still nearly useless on EFI-based computers.) (Windows tools like EasyBCD can help configure the Winddows boot loader's boot manager features, but I'm not very familiar with this tool myself. The Windows boot loader can also function as a boot manager, but it's more often configured to boot straight to Windows, so this functionality is less important - at least, when people set things up as Linux users generally do. GRUB, however, cannot directly launch a Windows kernel, so to boot Windows, GRUB passes control on to the Windows boot loader. GRUB presents a menu of options, like a boot manager but it can also directly boot a Linux kernel. Some programs, including GRUB, are both boot loaders and boot managers.

This distinction is pretty simple and easy to understand, but there are some complicating factors that can make the difference seem rather blurry: A program that functions exclusively as a boot manager does not directly launch an OS kernel, although the boot loader it launches will do so.

Boot managers present menus or command lines that enable you to launch particular boot loaders or other boot-related programs.

These are usually OS-specific, so you must use the Windows boot loader to boot Windows and a Linux boot loader (such as ELILO, GRUB, or the EFI stub loader) to boot Linux.

Boot loaders are programs that load an OS kernel into memory and pass control to the kernel.

It's important to understand the difference between two different tools: