MacOS – How to run OS X from DVD or USB stick

I have done this many times since I posted this question.

1. Create usb stick like this:

   sudo dd if=/<path to iso file>/<name of iso file> of=/<path to usb stick> bs=32768 conv=notrunc,noerror,sync
   

2. Put the USB stick into your Mac and press the power button while holding down Command ⌘+Option+O+F

3. At the prompt, type the following:

   boot usb1/disk@1:,\\yaboot
   

Note: If you are booting linux then use ,\\yaboot, but if you are booting a Mac OS use ,\\tbxi.

Note 2: If your stick is in the right side of the machine, then you need to do this:

boot usb0/disk@1:,\\yaboot

Note 3: If these commands don't work, then there is most likely a problem with your media or iso file.

I have found that Ubuntu, Debian, and openSUSE work great. I cannot get Fedora or Gentoo to boot this way yet. My optical drive does not work anymore, so this is how I install OS X on my machine. I made a live USB stick of the OS X install disc this way.

I can confirm that this process works:

https://fuerstnet.de/en/upgrade-crucial-m4-ssd-firmware-mac-without-cd

There are many steps to follow, both in creating the usb disk, then in booting from it, but it took me to the firmware updater as promised. After all that effort, my disk was already up-to-date, but it did work.

Crucial support says there is no option for people without a CD drive, but there is. You just have to be willing to carefully follow some instructions and be sure you're not writing to the wrong disk.