[EFI boot loader] --- https://www.pld-linux.org/efi?rev=1352031786 +++ https://www.pld-linux.org/efi @@ -25,11 +25,36 @@ ==== EFI boot loader ==== Not every boot loader is capable of booting from EFI firmware and it is not even necessary to use a dedicated boot loader to start Linux kernel. - The boot loaders with EFI support are: **ELILO** and **GRUB2**. ELILO needs the linux kernel and initrd images present on the EFI System Partition. GRUB2 can load them from a Linux file system (/boot partition, or even the root partition on LVM). + The boot loaders with EFI support are: **ELILO** and **GRUB2**. - Recent Linux kernel can boot directly from EFI with no extra boot loader. See below. + === ELILO === + + ELILO needs the linux kernel and initrd images present on the EFI System Partition. Specific paths and other options can be + configured in the 'elilo.conf' file placed in the same directory of the EFI System Partition where ''elilo.efi'' is placed. + + ''elilo.efi'' is provided by the **elilo** package, and is installed in the ''/lib/efi/x64'' (64-bit) or the ''/lib/efi/ia32'' (32-bit) directory. It must be copied to the EFI System Partition, together with the ''elilo.conf'' file (available in ''/etc/efi-boot''), the Linux kernel and initramfs images. [[#efi-boot-update]] can take care of that. + + ELILO can also be used for network (PXE) boot from the EFI firmware. + + === GRUB2 === + + GRUB2 can load the kernel and initramfs file or any other image to boot from a Linux file system (/boot partition, or even the root partition on LVM). The GRUB core image is installed at the EFI system partition by the ''grub-install'' command and additional GRUB modules are read from the /boot file system when necessary + + To install GRUB2 bootloader for (U)EFI booting: + + * install the **grub2** and **grub2-platform-efi** and **efibootmgr** packages. Most probably the x86_64 version of **grub2-platform-efi** package will be needed, as most modern EFI firmwares run 64-bit. + * make sure your EFI system partition is mounted at /boot/efi + * issue ''grub-install --target=x86_64-efi'' + + If the 'Couldn't open either sysfs or procfs directories for accessing EFI variables.' message is displayed, that means efibootmgr was not able to update boot manager configuration. It such case it may be necessary to use the EFI firmware configuration interface (equivalent of 'BIOS setup') to set up booting for ''\\EFI\\grub\\grubx64.efi'' or to copy ''/boot/efi/EFI/grub/grubx64.efi'' to ''//boot/efi/EFI/BOOT/BOOTX64.EFI'' file, to make it the default boot loader for the device. + + GRUB can also be used for network booting, but version 2.00-1 times out on large initramfs images (this makes PLD Rescue boot impossible). + + === no bootloader === + + Recent Linux kernel can boot directly from EFI with no extra boot loader. Also Xen hypervisor can be booted this way (in fact Xen may misbehave if booted under EFI other way). See below. ==== EFI-compatible kernel ==== === Linux kernel ===
Diff URL: https://www.pld-linux.org/efi?do=diff&r1=1352031786&r2=1352050330 -- This mail was generated by DokuWiki at https://www.pld-linux.org/ _______________________________________________ pld-cvs-commit mailing list [email protected] http://lists.pld-linux.org/mailman/listinfo/pld-cvs-commit
