Note: The following guide should work with any version of Linux, though these instructions are specific to Ubuntu 11.10. The process also involves formatting your entire hard drive (not just a partition) so be sure to back up all data before proceeding. Finally, major thanks to Hexxeh for his continued hard work.
This is just a walkthrough and should be enough information to guide you through the procedure. While it may look like a lot of steps, all it describes is installing Chromium OS, shrinking the H-STATE partition, and then installing Linux to the free space.
1. Boot into Chromium OS running from a USB drive (download here)
2. Sign in with your Google account, or select Guest
3. Hit Ctrl+Alt+t to be taken to a terminal window
4. Type install at the crosh prompt and hit enter
5. Enter password facepunch and hit enter
6. Allow the install to finish and then reboot
7. Boot to the Ubuntu Live CD/USB drive
8. Launch GParted and select the H-STATE partition
9. Right click on the partition and select Resize/move
10. Enter 5000 in the New Size field and click in the Free space following field to fill it with the remaining partition space. This will resize the H-STATE partition to ~5 GB and leave the remaining space for Linux
11. Click apply and then click the Check to start the partition shrink
12. Once it completes, close GParted and run the Ubuntu installer
13. Select the Something else option to choose which partitions to install to
14. Select the blank partition and we created earlier and click Add
15. Enter the size of your swap area and select swap area under the Use as drop down menu. Click ok
16. Select the remaining space, click Add, select Ext4 journaling file system under Use as, and / under Mount Point. Click ok
17. Select /dev/sda as the Device for boot loader installation and click Install Now
18. Let the install finish and reboot!
After POST, you should be presented with a Grub menu. Selecting Ubuntu will boot Ubuntu while selecting either of the “unknown Linux distribution on …” will boot Chromium OS. You can google how to remove/rename entries so that you only have one Chromium option. Enjoy!
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