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Subject: Re: A few stupid questions regarding MBR and boot0
To: "Andrey V. Elsukov" <bu7cher@yandex.ru>,
 Aleksander Alekseev <afiskon@devzen.ru>, freebsd-hackers@freebsd.org
References: <20160414144849.7a08b1db@fujitsu> <570F92D8.1000405@yandex.ru>
From: Julian Elischer <julian@freebsd.org>
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Date: Fri, 15 Apr 2016 19:03:39 +0800
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On 14/04/2016 8:53 PM, Andrey V. Elsukov wrote:
> On 14.04.16 14:48, Aleksander Alekseev wrote:
>> 1) If I understand correctly first 512 bytes of /dev/ad0
>> and /boot/boot0 file should match, but they don't:
>>
>> http://afiskon.ru/s/31/665dc9755c_mbr.txt
>>
>> Could someone please explain why they don't match?
> https://www.freebsd.org/cgi/man.cgi?gpart#BOOTSTRAPPING
>
As Alan said, there two alternate boot sectors.. the original, and an 
enhanced one htat allow syou to select from a compiled in menu.
The one that has 'inux' 'reeBSD'  in it is the menu one.
man boot0cfg