How to resolve angry beeping when GalliumOS refuse to boot

This time, I am going to post about a bit of troubleshooting with GalliumOS in my Chromebook. A little detour from my regular NextBus Compare project progress posting. This is more about working with developer tools, I guess.

I don’t actually use Chromebook that often since most of my work is on Macbook. As a result, it is not charge everyday. A few day, I forgot to turn it off. Left to its sleep mode, the battery completed drained itself.


If I just have ChromeOS, it wouldn’t be a problem – but my system is dual-boot with a Linux OS. GalliumOS to be precise. To boot into GalliumOS, I typically just do a simple Ctrl-L. But this time, there is an angry, angry beep and no boot.

Chromebook Alert: OS Verification is Off
Chromebook’s white screen, now stucked


I am almost certain it have to do with the battery drain, but what happened?

A bit more research on the documentation and GalliumOS reddit revealed that because the crossystem flag used for booting is a firmware level setting, it is therefore stored in volatile memory. When there is a complete drain, there is a possibility for the flag to be lost. To solve it, here are the steps:

  1. Boot into ChromeOS – yes, not GalliumOS, but ChromeOS. We need to access the developer mode! Usually, the command for ChromeOS booting is Ctrl-D.
  2. You may have to configure wifi if it is not set up. My Chromebook still remembers it, so it was good to go.
  3. Do a Ctrl-Alt-=> (=> is the right arrow on the first row your keyboard) – to boot yourself into the developer terminal.
  4. Enter chronos as username with no password.
  5. Enter sudo crossystem dev_boot_legacy=1. Some guides online may say dev_boot_usb, but as the GalliumOS documentation mentioned, that flag is not related to legacy boot issue. I should know – I tried it!
  6. Enter sudo reboot.
  7. Now the GalliumOS booting should be good to go!!!

One thought on “How to resolve angry beeping when GalliumOS refuse to boot”

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.