bin/48341: [sysinstall] sysinstall deletes mbr although it should not

[John Baldwin]

On Friday 16 June 2006 15:00, Heiner wrote:
> The following reply was made to PR bin/48341; it has been noted by GNATS.
> 
> From: Heiner <h.eichmann at gmx.de>
> To: bug-followup at freebsd.org,
>  freebsd-qa at freebsd.org
> Cc:  
> Subject: Re: bin/48341: [sysinstall] sysinstall deletes mbr although it should not
> Date: Fri, 16 Jun 2006 21:01:37 +0200
> 
>  I have now tested the installation of FreeBSD 6.1 on a machine with some other 
>  OS already existing. I've choosen 'none' as described in the bug description. 
>  The goal was to use the existing boot manager and point it afterwards to the 
>  FreeBSD installation as well.
>  
>  Result: the system was not bootable after the FreeBSD installation. An 
>  analysis shows, that the mbr was not deleted or destroyed; just the active 
>  flag was removed and the FreeBSD slice was set active. Setting the previous 
>  slice active resolved the problem!
>  
>  So the bug text should be replaced by:
>  
>  sysinstall changes the active slice flag although the corresponding sysinstall 
>  question was answered with "None - Leave Master Boot Record untouched"

Hmm, this is because the menu is not about leaving the MBR completely
untouched (we couldn't add new slices if we did that!) but instead about
leaving the boot code in the MBR untouched.  Note that the Active flag
isn't stored in the boot code, but in the partition table.  When you
create the FreeBSD slice in the MBR during installation, it will have
the Active flag set.  You can manually reset the Active flag on the
Windows partition before exiting that stage of the disk editor and
things should work as expected.  Would you be able to try that out and
verify that?

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org