Creating FreeBSD boot disks on Mac OS X


Do you have an older generation machine that can't boot from a CD-ROM and you would like to create a set of boot disks using your Mac OS X machine with a USB floppy drive? I did, and to spare you the trouble (and to help myself remember for future reference!) here's how to do it.

Firstly go grab yourself copies of the .flp floppy disk images from the FreeBSD FTP server.

Obviously you plug in your 1.44MB USB floppy drive in, then stick in a blank disk. Even if you're pretty sure the disk is blank it's a good idea to format it anyway to help detect bad sectors which can really screw up a FreeBSD installation (which can be really fun if you have other partitions with data on it!).

So to format your disk:

  1. Fire up Disk Utility in /Applications/Utilities/.
  2. Click your USB floppy drive in the devices column (should have a pretty little orange icon)
  3. Click the Mount/Unmount button to unmount the disk
  4. Click the Erase tab in the main window area, followed by the Erase push button

All good so far. If you get any errors during the process, most likely you have a dud disk. Just replace it and try again.

Now to make the disks. Basically you can follow the instructions in the FreeBSD Handbook, but instead of pointing to the "/dev/fd0" BSD device, point it to "disk1".

The drawn out steps:

  1. Go to your trusty Terminal also in /Applications/Utilities/.
  2. Use the cd command to navigate to the directory where you downloaded the .flp disk images, such as $ cd ~/Desktop/
  3. Punch in dd if=DISKIMAGE.flp of=/dev/disk1, replacing DISKIMAGE with the image you’re using.

If all goes well, you should get output similar to this:

rubenerd@vertias-r-mbp ~/Desktop$ sudo dd if=boot.flp of=/dev/disk1
2880+0 records in
2880+0 records out
1474560 bytes transferred in 203.249017 secs (7255 bytes/sec)
rubenerd@vertias-r-mbp ~/Desktop$

Good luck! Don't forget to also read up on the section in the FreeBSD handbook: 2.3.7 Prepare the Boot Media.

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Ruben Schade is a technical writer and infrastructure architect in Sydney, Australia who refers to himself in the third person. Hi!

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