Installing/Creating Bootable USB

Creating bootable GalliumOS media is very similar to other Linux distributions. Unfortunately, that doesn't mean it's easy. The goal of this guide is to make it as straightforward as possible.

On Linux

First, you need to download the GalliumOS iso for your Chromebook.

Once the iso is finished downloading (you MUST wait for it to finish), open up your favourite Terminal emulator.

cd to the place where you downloaded the iso. It's probably ~/Downloads.

cd ~/Downloads

Plug in your USB device, identify it, and unmount it. This is a little tricky. You can use lsblk to get a list of storage devices attached to your system. Try to find out which one is your USB flash drive. It is very important to not get this wrong, as it could cause catastrophic data loss. Once you've figured it out, make sure the USB flash drive is unmounted.

sudo umount -f /dev/sdb1

Be sure to replace sdb1 with the actual partition name as listed in lsblk. Next, use dd to copy the ISO to the USB flash drive.

sudo dd bs=1M if=galliumos.iso of=/dev/sdb ; sync

Be sure to replace galliumos.iso with the filename of the iso you want to write. Usually typing "galliumos" and hitting tab will autocomplete it for you. Also be sure to replace sdb with the actual device as listed in lsblk. Make sure to write to the DEVICE and NOT the partition. This process can take a long time depending on the speed of your flash drive, USB connection, and hard drive. Be patient. Once the prompt comes back, the ISO should be written.

If you are unable to boot your ChromeOS device using your new USB media, see Troubleshooting, below.

On Mac OS X

1. Download the GalliumOS ISO for your ChromeOS device: https://galliumos.org/download
2. Insert USB media into Mac OS X machine
3. Carefully determine device path for newly inserted USB media from a Terminal.app window
   bash$ diskutil list
   The device path will be something like /dev/diskN. Replace N in all steps below with the correct disk number.
   ⚡It is extremely important to determine the correct device path for your USB media in this step. Using the wrong device path in the following steps could damage your OS X install and cause irreparable data loss!
4. Unmount USB media from OS X
   
   bash$ diskutil unmountDisk /dev/diskN
5. Copy the ISO to USB media (dd works too, but cp is simpler and more familiar)
   
   bash$ sudo cp ./galliumos.iso /dev/rdiskN
   ★Be sure to use the correct path and filename for the galliumos.iso file downloaded in step 1, and to use the rdisk device name as the copy destination.
6. Eject USB media from OS X
   
   bash$ diskutil eject /dev/diskN
7. Remove USB media from Mac OS X machine, it's now ready for your ChromeOS device

If you are unable to boot your ChromeOS device using your new USB media, see Troubleshooting, below.

On Windows

1. First, download the correct iso for your device.
2. Wait for the download to finish completely before proceeding.
3. Also download, install, and open Win32DiskImager from [SourceForge]. If you already have it, just open it up.
4. Plug in your USB device and identify it's drive letter.
5. Click the folder button next to the empty box on Win32DiskImager.
6. Change the file type from Disk Images (.img) to *.*.
7. Use the file dialog to navigate to and open the GalliumOS iso from your Downloads folder (or wherever else it may have saved).
8. Select the letter of your USB drive from the dropdown in Win32DiskImager.
9. Click the Write button on Win32DiskImager.
10. If prompted to confirm overwrite or corruption of physical device, click Yes.
11. Wait for it to finish... It may take a while.
12. When you see the Write Successful popup, click OK.
13. Eject your USB drive before unplugging it.

If you are unable to boot your ChromeOS device using your new USB media, see Troubleshooting, below.

On ChromeOS

ChromeOS is very similar to Linux, but not identical. I will write a proper guide as soon as I have access to a Chromebook (that I haven't installed GalliumOS on :P)

Troubleshooting

Creating installation media is (by far!) the most error-prone step to installing GalliumOS.

There are many things that can go wrong. Some errors are immediately obvious (won't boot), others can be very surprising (installer crash, IO errors). If you're having trouble, consider this list of possibilities:

Common Problems

• Mistaken write: Human error happens! Please reread the instructions very carefully -- make sure you're writing to the correct device, and to the correct device file (which is different from the device file in other commands).
• Corrupt write: We frequently see corrupt writes to USB/SD media even when all steps are followed correctly. Sometimes the second or third try "just works", but confirm the MD5 checksum first.
• Bad USB/SD media: These devices aren't known for their reliability. Try a different USB drive or SD card if you are able.
• Wrong USB port: Some models and firmwares only boot from USB2.0 (black) ports, not USB3.0 (blue) ports. This is only a boot problem -- writing should work to either.

Less-Common Problems

• Corrupt image download: Compare the MD5 checksum for your download to the the published checksum. Replace galliumos.iso with the name of the file you downloaded, of course:
  • Linux: md5sum ./galliumos.iso
  • Mac OS X: md5 ./galliumos.iso
  • Windows: https://www.microsoft.com/en-us/download/details.aspx?id=11533
• Bad image: Sometimes we make bad nightly images! It's rare, but it has happened. Please let us know if you run into this problem. The ISOs linked from the GalliumOS download page are well-tested, so try one of those instead.

Testing your USB drive and write

The GalliumOS ISO should boot any x86 computer that allows "Legacy Boot" (this might require config in the BIOS menu). This is a safe test -- booting from the ISO launches a "Live" demo environment, which does not (automatically) attempt to install any software.

If all else fails, you might have better luck installing in a dual-boot config, which downloads directly from the GalliumOS servers, and does not require any installation media.