Re: UEFI equivalent of boot.config? (Was: Re: [RFC] Deprecation and removal of the drm2 driver)

> On 23 May 2018, at 13:29, sthaug_at_nethelp.no wrote:
> 
> Hijacking a thread here,
> 
>> Turns out, you can't install FreeBSD using a USB stick image because the
>> BIOS only support MBR. No idea why MBR support was dropped for the USB images.
>> 
>> In the end I had to find a CD burner, and after a couple of tries managed to
>> install from CD.
> 
> On a somewhat related note - I recently installed 11.1-STABLE on a box
> with support for both UEFI and "good old fashioned BIOS". I initially
> used UEFI and GPT, but ended up switching to BIOS and MBR because I
> needed boot.config to enable booting from an alternate partition.
> 
> Despite lots of Googling I couldn't find a simple way to do this using
> config stored on the disk itself (e.g. having "0:ad(0,f)/boot/loader"
> in /boot.config) with UEFI.
> 
> Does anybody know if this can be done using UEFI?
> 
> Steinar Haug, Nethelp consulting, sthaug_at_nethelp.no

it can but it a bit different situation there. you can not start bios boot loader from UEFI loader or vice versa, you only can use the same platform binaries.

for UEFI case, the boot1.efi does not process boot.config, so you have total 3 options - you switch boot disk in UEFI boot manager, or you use chain command to load either bootx64.efi from target disk ESP partition or you use chain command to load /boot/loader.efi from target disk freebsd root file system. You also can set currdev to point to new root, but usually you want a bit more (read in the configuration etc) so the chainload may be a bit easier.

Once you have figured out the proper file name to use with chain command, you can set chain_disk to have it as value and you will have chain menu entry… like chain_disk=zfs:zroot/ROOT/default:/boot/loader.efi

rgds,
toomas