Boot Menu Damaged

[E. J. Cerejo]

Jerry McAllister wrote:
> On Mon, Dec 31, 2007 at 10:46:04AM -0500, E. J. Cerejo wrote:
>
>   
>> ----- Original Message ----- 
>> From: "Jerry McAllister" <jerrymc at msu.edu>
>> To: "E. J. Cerejo" <ecerejo at optonline.net>
>> Cc: <FreeBSD-questions at freebsd.org>
>> Sent: Monday, December 31, 2007 9:50 AM
>> Subject: Re: Boot Menu Damaged
>>
>>
>>     
>>> On Mon, Dec 31, 2007 at 01:17:51AM -0500, E. J. Cerejo wrote:
>>>
>>>       
>>>> I'm running FreeBSD 6 stable and I lost my boot menu after reinstalling 
>>>> xp
>>>> and tried to fix it by booting with instalation cd and run "fdisk -B -b
>>>> /boot/boot0 /dev/ad0" it restored it but when I boot I get the mountroot>
>>>> prompt, it fails to mount ad0s2a, b, c, d.  Is it possible to fix this or
>>>> do I have to reinstall freebsd?
>>>>         
>>> It may be that you got the slices no longer marked as bootable.
>>> Try using fdisk(8) or boot0cfg(8) to re-enable booting on those slices.
>>>
>>> ////jerry
>>>       
>> Do you run it from the instalation CD using fixit or run from the mountroot 
>> prompt on the computer.  It seems to me I can't can any commands from this 
>> prompt. 
>>     
>
> I would do it from the fixit.
>
>   

Well that didn't work but I finally fixed it.

from the moutroot I was able to go into single user mode by running 
these commands:

ufs:/dev/ad0s2a
fsck -p /
mount /

after this I was able to check and fix my /etc/fstab file, for some 
reason the mount points got all changed to slice 4, e.g. ad0s4a, changed 
them back to ad0s2a and so on, after that I was able to boot just fine.  
How it happened I have no idea.