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| howtos:slackware_admin:set_up_syslinux_as_boot_loader_on_uefi_based_hardware [2016/08/17 10:31 (UTC)] – typo tonberry | howtos:slackware_admin:set_up_syslinux_as_boot_loader_on_uefi_based_hardware [2016/08/18 23:53 (UTC)] (current) – typo tonberry |
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| ===== Why UEFI ===== | ===== Why UEFI ===== |
| It is not as though there is some choice; machines nowadays //are// UEFI. One can, however, chose to set UEFI to so called "CSM" or sometimes "Legacy" mode. In this mode, UEFI acts as BIOS, i.e. reads the first sector (MBR) of a hard drive and loads and executes non-UEFI boot loader such as LILO from there. As opposed to UEFI in, say, UEFI mode, when it reads, loads and executes UEFI-aware boot loader from //EFI boot partition//. | It is not as though there is some choice; machines nowadays //are// UEFI. One can, however, choose to set UEFI to so called "CSM" or sometimes "Legacy" mode. In this mode, UEFI acts as BIOS, i.e. reads the first sector (MBR) of a hard drive and loads and executes non-UEFI boot loader such as LILO from there. As opposed to UEFI in, say, UEFI mode, when it reads, loads and executes UEFI-aware boot loader from //EFI boot partition//. |
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| Frankly, there are no compelling reasons not to use CSM (note that it is possible to use [[http://docs.slackware.com/howtos:slackware_admin:installing_with_gpt_without_uefi | GPT partitions without UEFI]]). On the contrary, there are reasons to avoid UEFI booting, because: | Frankly, there are no compelling reasons not to use CSM (note that it is possible to use [[http://docs.slackware.com/howtos:slackware_admin:installing_with_gpt_without_uefi | GPT partitions without UEFI]]). On the contrary, there are reasons to avoid UEFI booting, because: |
| * ''INITRD initrd.gz-4.4.14'' is an initrd image that is mounted as temporary / before the final / is mounted. Typically, an initrd is needed if kernel has to load some additional modules to access the root device, or has to perform some actions to make it accessible (think of RAID, LUKS, LVM). If you do not need initrd, simply delete this line. | * ''INITRD initrd.gz-4.4.14'' is an initrd image that is mounted as temporary / before the final / is mounted. Typically, an initrd is needed if kernel has to load some additional modules to access the root device, or has to perform some actions to make it accessible (think of RAID, LUKS, LVM). If you do not need initrd, simply delete this line. |
| * The second menu entry is largely the same, except that there is no '4' in ''APPEND /dev/vgroot/V_ROOT''. Simply put, this is non-graphical safe mode. If X window system fails to start for whatever reason, you may end up with not only black screen, but also blocked keyboard and mouse and therefore unable to fix the cause. So it is a good idea to have this option prepared beforehand (another method to use otherwise unusable machine with broken X is to SSH-in, though it is a less reliable method). | * The second menu entry is largely the same, except that there is no '4' in ''APPEND /dev/vgroot/V_ROOT''. Simply put, this is non-graphical safe mode. If X window system fails to start for whatever reason, you may end up with not only black screen, but also blocked keyboard and mouse and therefore unable to fix the cause. So it is a good idea to have this option prepared beforehand (another method to use otherwise unusable machine with broken X is to SSH-in, though it is a less reliable method). |
| <file /boot/efi/EFI/SYSLINUX/syslinux.cfg> | <file - /boot/efi/EFI/SYSLINUX/syslinux.cfg> |
| UI menu.c32 | UI menu.c32 |
| PROMPT 0 | PROMPT 0 |
| </file> | </file> |
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| * Still in /boot/efi/EFI/SYSLINUX, copy kernel here. Huge is a safer option. Generic may require initrd and more modules in it. If you do not know which they are, the machine might not boot, so go with the huge. | * Still in /boot/efi/EFI/SYSLINUX, copy kernel here. Huge is the safer option. Generic may require initrd and more modules in it. If you do not know which they are, the machine might not boot, so go with the huge. |
| <code> | <code> |
| # cp /boot/vmlinuz-huge-4.4.14 . | # cp /boot/vmlinuz-huge-4.4.14 . |
