Resetting bootloader on a CF

Polytropon freebsd at
Thu Sep 1 07:59:44 UTC 2011

On Wed, 31 Aug 2011 23:47:22 +0200, bsd wrote:
> Part of the solution seems to be : 
> 1. Mount the CF on a FBSD 
> 2. Initialize the bootloader with : 
> # fdisk -B /dev/<disk>

Erm... You should _not_ mount (as in /sbin/mount) the CF
in order to change MBR data; mounting should be restricted
to its humano-mechanical part. :-)

> 3. This is where I need you help… 
> How can I re-install a boot loader ? 
> Should I use the command : 
> # fdisk -B -b /boot/boot0 device
> Any other suggestion, guidance will be welcome. 

You can use sysinstall for that: Configure, select the CF card
to work on, don't chance anything with the slices in the fdisk
editor, just make sure the slice is marked active, and in the
next step, select the default MBR to be written.

The command line way should be:

	# fdisk -BI /dev/da0
	# fdisk -B -b /boot/mbr /dev/da0

(Assumption: /dev/da0 is the CF card.)

Note that the first step will re-initialize the card. If you don't
want to build it from scratch, i. e. _only_ modify the MBR, the
second command should do it.

See "man fdisk" for details on the fdisk commands.

Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...

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