9.0 beta2 & the new bsdinstaller

[Andriy Gapon]

on 18/09/2011 23:18 Kevin Oberman said the following:
> On Sun, Sep 18, 2011 at 2:55 AM,  <"Thomas Mueller
> <mueller6727"@bellsouth.net> wrote:
>> Some more ideas on the new bsdinstaller cross my mind.
>>
>> Since the way the bsdinstaller would make partitions is unpredictable, at least to the uninitiated, and in all likelihood at variance with how much space the user wants to allocate, it might be better to offer a roadmap to help guide the user to allocating space for FreeBSD using gpart or Rod Smith's gdisk.
>>
>> Also, I can't see the function of the 64 KB boot partition with no file system, which does not boot for me, though I can boot the main partition using grub2 from the System Rescue CD (http://sysresccd.org/).
> 
> The 64KB freebsd-boot partition is to contain the GPT boot code which
> is used by UEFI BIOS in
> place of the old MBR used by legacy BIOS. You need to use gpart(8) to
> write the GPT boot code to that partition, but I don't know if
> bsdinstall does so. It might just write the PMBR that is used for
> booting with legacy BIOS. I'll admit that I have not checked. (See the
> gpart(8) man page for details on writing the pmbr and gptboot.)  I
> assume bsdinstall writes both so that AMD64 machines with EFI and
> 32-bit systems will both work. This is very different from the old
> traditional slice/partition system.

I don't think that we create a GPT boot partition that is going to be used by
UEFI BIOS.  We use specific "freebsd-boot" partition type, which, I am sure, is
unknown to BIOSes.
So, as you say, we install PMBR, which will be booted by BIOS, and which will
then load the "main boot code" from the boot partition.

-- 
Andriy Gapon