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On Friday, 25 October 2019 15:28:27 BST Peter Humphrey wrote: |
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> At the next reboot, the UEFI BIOS starts the system directly; it doesn't |
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> show a menu of boot images. But I want that list so that I can choose which |
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> image to boot. |
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The UEFI firmware does not display a list of bootable devices the user could |
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choose from, *unless* you enter the firmware/BIOS GUI before booting of an OS |
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commences, or you boot into a UEFI shell application. To launch the UEFI |
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firmware/BIOS GUI usually requires pressing F2 on start up or some FXX button, |
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depending on the MoBo. On some laptops there is a separate button for this |
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purpose. |
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> Now if I repeat those last two commands but with "--unicode '...'" omitted, |
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> expecting those values to be picked up from /boot/loader/entries/30- |
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> gentoo-4.19.72.conf, the BIOS starts some unconfigured kernel - which panics |
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> because it can't find its filesystem. Again, it doesn't show me a menu, |
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> just goes for it. |
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Without the '--unicode' option the efibootmgr uses ASCII to pass extra command |
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line arguments, so it could well be your root, initrd, or net options are mis- |
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translated and/or ignored. |
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Entries in /boot/loader/entries/30-gentoo-4.19.72.conf are parsed and |
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interpreted by the systemd-boot Boot Manager application, not by the UEFI |
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firmware itself. |
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> I may have the directory layout wrong under /boot, and that may be my |
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> problem. I think I used a layout from systemd-boot, which I no longer use. |
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> |
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> Can anyone see what I'm doing wrong? Do I have to go back to bootctl from |
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> systemd-boot? |
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If you intend to have a list of available OS kernels displayed for you to |
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choose from at boot time, then you need a Boot Manager (eLILO, GRUB, systemd- |
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boot, et al.) and will *have* to follow the respective Boot Manager's |
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conventions regarding its configuration and storage/naming of kernel images. |
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Without a 3rd party Boot Manager you will be using the UEFI firmware's |
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embedded boot manager, which is accessible at start up via the firmware/BIOS |
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GUI, or in some MoBos via the UEFI shell. For those MoBos that support |
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running it, the UEFI shell can be launched with F6, F11 or F12 keys. |
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Otherwise, you may have to install and configure <ESP>/shellx64.efi as the |
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image to boot with. |
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If your think entering the firmware/BIOS GUI, or running UEFI shell commands |
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(bcfg plus options), each time you want to boot an OS will soon wear thin, the |
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use of a 3rd party Boot Manager with its convenient boot menu is probably a |
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more suitable option. |
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PS. Happy to discuss specifics off-list if you think this is less of a Gentoo |
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issue. |
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-- |
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Regards, |
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Mick |
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