On Sun, 29 Sep 2019 at 13:25, Neil Bothwick <n...@digimed.co.uk> wrote: > > On Sun, 29 Sep 2019 11:59:00 +0100, Mick wrote: > > > As I understand it, 'bootctl --update' can be used to update > > systemd-boot boot manager's menu and it is looking for bootable > > kernels by scanning /efi, /boot, and /boot/efi, or the directory set > > by passing the '--path' option to it. Manual addition of bootable > > kernels must be set via /loader/entries/*.conf (one file per kernel > > image) and then setting the default kernel to be booted in > > /loader/loader.conf. I find all this to be unnecessary complication > > for maintaining a boot manager manually, compared to using say > > efibootmgr. However, it is handy to be able to press 'e' to edit the > > default entry at boot time, or if new kernels are always stored where > > expected by the scripts of binary distros. > > > > For Peter's use case, OS and kernel resides on secondary disk, the > > solutions I can think are: > > > [snip GRUB bit] > > > 2. Use systemd-boot. Copy each kernel from the secondary disk to > > /boot/EFI/ creating the corresponding /loader/entries/*.conf, adding > > the kernel .conf name and the OS root partition's path on the > > secondary disk. The root path can also/instead be included in the > > kernel itself (CONFIG_CMDLINE). > > That's not how the systemd boot manager works. It is a bootable image > which then reads the config from /boot/loader and presents a boot menu. > As far as the firmware is concerned, it is always booting the same image.
Thanks Neil, I bow to your superior knowledge on systemd-boot - I've only come across it on binary distros and did not have to interfere with its settings. I think we're saying the same thing. I understand that using a predictable naming convention for *.conf files will load the corresponding kernel images in turn, but the default kernel can be overwritten in loader.conf instead of using a wildcard which will pick up the first *.conf file in line. Also, these .conf files will not be created with 'bootctl --update' unless all requisite OS kernel images have been stored in the ESP. > The loader files are analogous to grub.cfg, but a thousand times simpler > (I may be understating that in my desire to avoid hyperbole). For > example, loader.conf here is > > timeout 3 > default 00-* > > This never needs to be modified, it simply boots the first entry after 3 > seconds. Right, but if the OP wants to boot some other kernel (which happens to be on his second disk) systemd-boot's image picking up the first *.conf file won't be of use. He'll need to select another kernel from the menu or set this in the loader.conf as a semi-permanent solution. Please correct as necessary if I got this wrong. > Incidentally, I use a short shell script to regenerate the menu entries > after a kernel change, like grub-update but the predictable orders of > magnitude shorter, so even that is trivial. Yes, I expect Peter will also need to use some script of sorts if he wishes to automate this process, or manage it manually. -- Regards, Mick
