On Mon, Mar 7, 2011 at 2:22 AM, marc <li...@drwx.org> wrote:
> * If I do it from the existing openbsd in my drive, /dev/sd0a, I get
> device busy.
>
It is not clear from your narrative what is the device node for your hard
drive. The FAQ boldly warns following the dd(1) command:
> Note: this is a really good time to remind you that blindly typing
> commands in you don't understand is a really bad idea. This line will
> not work directly on most computers. It is left to the reader to adapt
> it to their machine.
There is no way that the FAQ can anticipate whether users will have IDE,
SCSI, or SATA hard drives, so some investigation must occur on your part to
determine whether the hard drive used is wd(4) or sd(4). One of the easiest
ways to find the answer is to search through the output of dmesg(8). On my
older Thinkpad, I get:
$ dmesg | grep sd
sd0 at scsibus2 targ 1 lun 0: <Corsair, Flash Voyager, 1.00> ATAPI 0/direct
removable
sd0: 978MB, 512 bytes/sec, 2002944 sec total
sd0 detached
$
...which gives details on a USB flash drive which had been attached at one
time, and:
$ dmesg | grep wd
wd0 at pciide0 channel 0 drive 0: <HTS541060G9AT00>
wd0: 16-sector PIO, LBA, 57231MB, 117210240 sectors
wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 5
$
...which is my actual hard drive in my laptop. What you will find may be
entirely different (including the appended number to the end of the
device...), but the driver reported must be reflected in the dd(1) command
used. If I wanted to create the PBR for my laptop, I would use the
following:
# dd if=/dev/rwd0a of=openbsd.pbr bs=512 count=1
If I were to blindly (& incorrectly) run the command stated in the FAQ, I
would get the error "Device not configured". You mention "device busy".
Did you run this command as root (which is the meaning of the "#" shell
prompt...)?
* If I boot with the cd rom neither msdos nor ntfs are available so I
> can't write the .pbr file to an accessible place from windows.
> * If I boot with the cd rom and write the .pbr file in the bsd filesystem,
> I can't read it from windows 7 (I couldn't find a program to mount bsd
> filesystems which works with windows 7).
>
You haven't thought through the ramifications of the MBR active flag. The
MBR contains entries for four possible primary partitions. Only one of them
will be marked active. When the system is next booted, the BIOS will search
through these four entries to determine which primary partition will be
searched for an operating system. Boot managers are simply elaborate
gimmicks to easily set the active flag. fdisk(8) can be used to change the
active partition. In fact, you could use OpenBSD's fdisk(8) to change the
MBR's active flag to next boot Windows, & bcdedit (as I recall...) within
Windows to change the active flag to next boot OpenBSD, but this is
laborious.
If you chose "whole disk" when prompted with the following question during
installation:
Use (W)hole disk or (E)dit the MBR?
...the active flag will have been set automatically for OpenBSD's
partition. If "(E)dit" is chosen, you can set it manually to whatever
partition you wish. Also, if you chose "whole disk", I can only hope you
backed up your Windows partition as it may not be there now.
Studying the FAQ before attempting multibooting as a newcomer is required.
Thinking is too.
> Does anybody have a solution to any of these problems or a 4th way?
>
The biggest problem seen in your message is a failure to grasp the nuances
of the boot process or the needed commands. You can overcome this, but it
will require attention to detail & tenacity.
> I had the impression that the command:
>
> <<C:\Windows\system32> bcdedit /set {0154a872-3d41-11de-bd67-
a7060316bbb1}
path \openbsd.pbr>>
>
> requires that the openbsd.pbr file is at located at the root of c:\. Am I
> wrong?
This is correct. As I recall, Windows 7 has less restrictions on where the
PBR is located, but for the purpose of the FAQ, putting the PBR in C:\ is
fine. bcdedit simply needs to be instructed as to its location.
Also recognize that the GUID used in the commands issues on your computer
are system-dependent. Don't simply cut-and-paste from the FAQ. Doing so
will result in a misconfigured boot manager.
Good luck.
