[Eisfair] Problem mit dem aktuellen Installer

[Thomas Bork]

Am 01.12.2019 um 17:13 schrieb ich:

>> dieses bekommt man mit
>> a   toggle a bootable flag
>> und dann
>> w   write table to disk and exit
>> wenn ich das durchführe, booten meine Maschinen damit auch.
> Ich vermute eher, dass Dein BIOS mit GPT und dem "legacy BIOS bootable" 
> ein Problem hat...

Interessant:
https://unix.stackexchange.com/questions/325886/bios-gpt-do-we-need-a-boot-flag

{...]
Your /boot partition does not need a boot flag and should not have one.
However, the sole partition in the protective MBR may need a (legacy) 
boot flag if the firmware of your computer wants it. (Some BIOSes won't 
boot a hard disk unless it has a primary MBR partition with the active 
flag set.)
Not all computers support booting from GPT disks under BIOS or BIOS 
emulation. In fact, this is explicitly unsupported. It usually works, 
though.

Dein Rechner fällt unter "(Some BIOSes won't boot a hard disk unless it 
has a primary MBR partition with the active flag set.)"


Aber:
https://wiki.archlinux.org/index.php/partitioning

[...]
Some old BIOSes (from before year 2010) attempt to parse the boot sector 
and refuse to boot it if it does not contain a bootable MBR partition. 
This is a problem if one wants to use GPT on this disk, because, from 
the BIOS viewpoint, it contains only one, non-bootable, MBR partition of 
type ee (i.e., the protective MBR partition). One can mark the 
protective MBR entry as bootable using fdisk -t mbr /dev/sda, and it 
will work on some BIOSes. However, the UEFI specification prohibits the 
protective MBR partition entry from being bootable, and UEFI-based 
boards do care about this, even in the legacy boot mode. So, this 
matters if one wants to create a GPT-based USB flash drive that is 
supposed to boot both on modern UEFI-based boards and also on old BIOSes 
that insist on finding a bootable MBR partition. It is not possible to 
solve this problem using traditional tools such as fdisk or gdisk, but 
it is possible to create a fake MBR partition entry suitable for both 
kinds of BIOSes manually as a sequence of bytes.
[...]

-- 
der tom
[eisfair-team]