Installing Ubuntu from USB on a Mac can seem impossible at first… but it’s not!
Create Ubuntu USB Stick
First download an Ubuntu iso from www.ubuntu.com/download
Be sure to get the 64bit+mac desktop version.
The first step is to convert the iso to a dmg using the terminal:
hdiutil convert -format UDRW -o ~/Downloads/ubuntu.dmg ~/Downloads/ubuntu-11.10-desktop-amd64+mac.iso
Run the command “diskutil list” without your usb stick in, then again once the stick has been inserted. The output from the second command should look something like:
diskutil list /dev/disk0 #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *121.3 GB disk0 1: EFI 209.7 MB disk0s1 2: Apple_HFS Macintosh HD 120.5 GB disk0s2 3: Apple_Boot Recovery HD 650.0 MB disk0s3 /dev/disk1 #: TYPE NAME SIZE IDENTIFIER 0: FDisk_partition_scheme *16.0 GB disk1 1: Windows_FAT_32 16.0 GB disk1s1
As you can see, disk1 has appeared since the insertion of the USB stick. It is very important you work out which disk your USB stick is in this way, else the next step will cause you to wipe out data on your Macbook Air’s SSD!
Now run:
diskutil unmountDisk /dev/disk1
Substituting disk1 for your USB stick’s disk number.
Next we’re going to write the image to the stick like so:
sudo dd if=~/Downloads/ubuntu.dmg of=/dev/rdisk1 bs=1m
Note that this time we’ve added an r to the front of disk1, this is not essential, but will speed up the process.
Finally, once the above command has executed, run “diskutil eject /dev/disk1” again replacing disk1 with your own stick’s reference.
Your USB stick has been created, restart your Macbook Air holding the alt key and choose to boot from the stick.
Installation
As soon as you see the purple screen with the white icon at the bottom, hit any key to get the USB stick’s boot menu. Select your language then press F6 and select the nomodeset option. Press ESC to return to the main menu and select “Try Ubuntu without any change to your computer”.
Proceed with the installation as normal, once finished, reboot the machine and hold down alt. Ubuntu will show up as “Windows”, select this option.
After a short pause you will see Grub and a list of boot options, press “e” to edit the default boot options. You will be presented with several strings of text, the penultimate line begins “Linux…” scroll along this line and add “nomodeset” directly before “quiet splash” so that it now reads “… nomodeset quiet splash …”.
Press ctrl+x to boot Ubuntu.
Fixing things…
First things first, install any updates that have come out since 11.10 was released:
sudo apt-get update
sudo apt-get upgrade
Now reboot. Yes, I know, how Windows-like… but we are about to start playing with your kernel and it’s a good idea to be using the new one you’ll have just installed through updates! Don’t forget to use the nomodeset trick from above again (don’t worry… this should be the last time!).
Now we’re going to run the incredible post-install-oneiric.sh script from almostsure.com:
wget http://almostsure.com/mba42/post-install-oneiric.sh
chmod +x post-install-oneiric.sh
./post-install-oneiric.sh