Making bootable USB keys

Samuel Martín Moro faust64 at
Fri Sep 4 07:51:58 UTC 2009

In fact, we provide the servers and the keys.
So we're sure everything will work.

And also, our install CD is already able to create this kind of USB stick.
It was a former co-worker who did it.
I started mine looking its. But most of used commands haven't exact
equivalent under linux (and I fucking hate sfdisk and counting in

Here's an example of a generated stick:
h2g2:~# fdisk da0
******* Working on device /dev/da0 *******
parameters extracted from in-core disklabel are:
cylinders=493 heads=255 sectors/track=63 (16065 blks/cyl)

parameters to be used for BIOS calculations are:
cylinders=493 heads=255 sectors/track=63 (16065 blks/cyl)

Media sector size is 512
Warning: BIOS sector numbering starts with sector 1
Information from DOS bootblock is:
The data for partition 1 is:
sysid 11 (0x0b),(DOS or Windows 95 with 32 bit FAT)
    start 63, size 6602652 (3223 Meg), flag 0
        beg: cyl 0/ head 1/ sector 1;
        end: cyl 410/ head 254/ sector 63
The data for partition 2 is:
sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
    start 6602715, size 1317330 (643 Meg), flag 80 (active)
        beg: cyl 411/ head 0/ sector 1;
        end: cyl 492/ head 254/ sector 63
The data for partition 3 is:
The data for partition 4 is:

Samuel Martín Moro
{EPITECH.} tek4

On Fri, Sep 4, 2009 at 6:31 AM, Fbsd1 <fbsd1 at> wrote:

> Samuel Martín Moro wrote:
>> Hello
>> I'm having some troubles, trying to create bootable USB keys.
>> I found (freebsd-hackers ML archives) a script, supposed to create the
>> bootable image from my iso file.
>> But, it still don't boot... (I may do it wrong)
>> In details:
>> -We distribute a FreeBSD (4.7, 5.4, 6.2 and 7.2) "custom" server.
>> -We burn our install CD (and, in a few, our USB sticks) on a Ferdora 9
>> (sorry...)
>> -USB sticks must contain a FAT32 partition (we'ld like to provide doc for
>> windows users)
>> Well, my english isn't so great... so I'll post my code (more
>> understandable)
> clip ----
> I have same problem with getting a usb stick to boot. After much testing
> with different sticks and PC combinations have come to this conclusion.
> When usb hardware first can out they were created for usb 1.0 standard and
> at that same period PC's where using software drivers for usb support and
> the PC's bio's boot selection did not include option to boot from usb disk.
> As usb devices became more popular PC manufactures started adding USB
> firmware to their motherboards for usb 2.0 standard. From my research into
> usb 2.0 it only supports data recording and does not support booting
> function. About 2007 usb 2.2 standard came out and it supports an usb memory
> stick as bootable. In 2008 some manufactures of motherboards added usb 2.2
> standard to their motherboards and bio's selection to boot from memory
> stick.
> To be bootable the first file on the the stick has to be the boot image.
>  Haveing a ms fat partition first on the stick will never work unless you
> fill it with an bootable ms/windows or ms/dos system or the same kind of
> setup found on the cdrom1 release cd.
> Only usb 2.2 memory sticks are bootable on newer PC's that have usb 2.2
> firmware on their motherboards and matching Bio's with selection for booting
> from usb 2.2 memory sticks. Please note that bio's booting selection for
> booting from USB disk is different than booting selection for booting from
> usb memory stick. I have posted many posts on this list about this subject
> and have not received any posts contrary to the above statement.
> The pending 8.0 release has a complete rewrite of the USB code and a new
>  stick.img is being generated as part of the release install distribution's.
> I can dd the 8.0-stick.img file to an 2.0 stick and it never boots, but do
> the same thing to a 2.2 stick and it boots on all 3 of my PC manufactured
> since June 2008.
> Final Conclusion: Booting from a USB memory stick successfully is totally
> dependent on using new start-of-the-art hardware.

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