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I have a brand new mac mini (core i5). I've yet to install OSX. I'd like to install OpenBSD from a USB drive. I do not want to dual boot, just run OpenBSD.

I used a different machine to transfer the amd64 install52.iso to a USB drive using dd if=install52.iso of=/dev/disk. I can mount the USB and the contents look good. However, I can't seem to get the mac mini to boot to the USB drive. Holding alt down during boot shows two partitions (one rescue one normal) but not the image on the USB drive. Holding c when booting doesn't seem to do anything but delay the boot of the OSX installer.

Any suggestions?

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So I think the first problem is dd is not creating a bootable image. I put the USB into a windows machine and got "no boot sector" when booting from USB. – paxos1977 Jan 7 '13 at 15:27
up vote 2 down vote accepted

Simpliest thing to do: on a 64 bit pc with cd drive put the openbsd install cd and plug the usb flash drive, boot and install on the flash drive as a regular disk. When finished, copy*tgz in the directory /5.2/amd/ on the flash drive. Then plug this flash drive in the mac mini and at the boot prompt type "boot hd0a:/bsd.rd", proceed as usual and when prompted for sets choose "/5.2/amd". That should work (I don't have any mac), at least it works on any pc/netbook/notebook, let me know plz ;)

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This worked beautifully. bsd.rd runs on the mini great... bsd not so much, there is a kernel panic. Booting "bsd -c" takes you into config mode but the usb keyboard drops out. So it is going to take a bit of work to get this panic reported/fixed. – paxos1977 Mar 19 '13 at 16:15

You need to install OpenBSD on the USB flash drive first, just as it's a regular disk install. Using dd just won't work.

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"regular disk install" is a little misleading. You need to burn the iso onto the usb drive and set it as bootable, which is different from "installing" it. – Marcus Chan Feb 3 '13 at 10:14
@MarcusChan so how do I get an ISO onto the USB drive and set it as bootable? – paxos1977 Feb 4 '13 at 17:30
There are numerous programs and techniques to do this; invariably for me the easiest way is Ubuntu's Startup Disk Creator tool or UNetbootin. I actually haven't seen a foolproof commandline solution yet... – Marcus Chan Feb 4 '13 at 20:49

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