I was hesitant about creating this tutorial, as the process of setting up the live USB is a bit finicky. The good news is, once you’ve got it working, it should keep working.
I feel creating a live USB is basically a necessity on the DGX Spark, since NVIDIA’s restore process is convoluted, unreliable, offers no live system that can be used to back up your files before a complete format of the internal SSD occurs, and after restoration doesn’t even leave you with a running system, instead forcing you to take updates, which, as seen during the bootloop fiasco is not a good thing. So out of frustration, I ventured to find a better way.
For those wondering what Timeshift is, it’s a program used to back up the system files on a Linux system. It will generally snapshot the system files periodically (I like doing it after every boot), and then at any time if something goes funny, you can restore an earlier snapshot of the system files, which only takes a couple of minutes. If you don’t already have a Timeshift backup I would HIGHLY recommend installing it and setting it up, it has already saved me from having to reimage my DGX Spark twice now. For this Tutorial I’m going to assume you already Timeshift installed (sudo apt install timeshift) and have made a backup of your system files.
Firstly, plug in your USB drive, and in the ‘Disks’ application:
- Format the drive as GPT (GUID Partition Table)
- Add a small (~500MB) FAT partition for the EFI files
- Add a big EXT4 partition for the system itself
Basically, you are mirroring the drive setup of the internal storage of the DGX Spark, as shown in the screenshots below:
The Drive should end up looking like this:
With your USB prepared, open up Timeshift, and restore a snapshot of your choosing to the USB:
- Set / to USB_UBUNTU
- Set /boot/efi to USB_EFI
- Under bootloader options, select the unchecked box as well
- Start the restore
- Note that it will appear to be frozen in the final step where it configures the bootloader, not sure what’s up with that, just walk away and come back 2 hours later and it should be done.
It will look like it is stuck on this final step where it says updating bootloader, just wait patiently, it will eventually finish:
Now I wish I could say you’re done once this finishes, but this is where we get to the finicky part, for some reason, the USB created at this point is almost always non-bootable, and it’ll just boot back into the normal OS if you attempt to boot from it. The only way to see is to try it.
You can do so by rebooting and repeatedly hitting the DEL key until you are in the BIOS, at this point, under save & exit, you can pick the boot option highlighted in the screenshot below:
If it doesn’t work, you’ll have to do the Timeshift restore again (but luckily it’s much faster during subsequent runs), this time, pick your EFI partition under bootloader options (in theory, only the EFI partition should be needed, but for some reason, picking just that option on its own never seems to work, it’s as if it really wants some weird combination of both the MBR and EFI options). The bootloader options should look like this during the second restore:
After that, try it again, hopefully it’ll work, if it really doesn’t, you’ll just have to try the restore again with the other bootloader option selected. As I said, it’s finicky but once you have a working USB, you’re all set, and it should already have Timeshift installed, so you can restore your system to a running state even if you can’t boot.
Since you (hopefully) aren’t using Timeshift to back up your home folder, it should be fairly obvious if it’s booting from the USB as it’ll pop up the Welcome to Ubuntu wizard if it worked.