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I'm attempting to install OpenBSD on a fancy new home server equipment I just bought.

I followed this guide to create a bootable USB flash drive from an OpenBSD VM I have on my laptop. But when I try to boot my laptop on it all I get is a "No OS" message. I tried two different USB keys.

Does anyone know that problem and its solution?

Edit : fdisk on sd0 in the VM :

#fdisk sd0
Disk: sd0   geometry: 122/255/63 [1974271 Sectors]
Offset: 0   Signature: 0xAA55
            Starting         Ending         LBA Info:
 #: id      C   H   S -      C   H   S [       start:        size ]
 0: 00      0   0   0 -      0   0   0 [           0:           0 ] unused      
 1: 00      0   0   0 -      0   0   0 [           0:           0 ] unused      
 2: 00      0   0   0 -      0   0   0 [           0:           0 ] unused      
*3: A6      0   1   1 -    121 254  63 [          63:     1959867 ] OpenBSD     
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what steps did you follow to make the USB drive's MBR bootable? the "No OS" message may be the BIOS telling you it can't find a bootable MBR. this means either you've failed to make the MBR bootable, or the BIOS isn't actually trying to boot from that USB drive. – quack quixote Apr 25 '10 at 20:25
What does fdisk sd0 say in the OpenBSD VM (assuming your USB drive shows up as sd0 in OpenBSD)? Is the asterisk indicating the bootable flag showing up next to the right MBR partition? – Niten Apr 25 '10 at 20:57
up vote 4 down vote accepted

Instead of following that guide, why not just plug the usb stick into your main computer, boot from a CD, and install OBSD on the USB stick as if it were a regular Hard Drive? That's what I did and now I have a wonderful "live" USB stick to play around with that I can also use for installing OBSD.

Here's the directions right on's web site.

To use it as an install guide, put bsd.rd under / on the drive. When you boot the drive, tell it to use bsd.rd. That'll start the install.

I put the other install files under /usr/local//

Once I've boot bsd.rd, I just point to that location to install OpenBSD.

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