Run UBOS from a boot stick on a PC (64bit)


You can install UBOS on a USB flash drive, and boot a standard PC directly from it. This will leave your PC’s hard drive unchanged and lets you try out UBOS easily.

A 16GB USB flash drive is recommended.


UBOS is a 64bit operating system. All recent PCs support 64bit; older hardware may not.

Follow these steps:

  1. Download a UBOS boot image from the Depot. Images for x86_64 are at Look for a file named ubos_green_x64_64-pc_LATEST.img.xz.

  2. Optionally, you may now verify that your image downloaded correctly by following Verify your downloaded UBOS image.

  3. Uncompress the downloaded file. This depends on your operating system, but might be as easy as double-clicking it, or executing

    % sudo xz -d ubos_green_x86_64-pc_LATEST.img.xz

    on the command line.

  4. Write this image file “raw” to a USB flash drive. This operation depends on your operating system:

  5. Remove the USB flash drive, insert it into a PC that is currently off, and boot that PC from the USB flash drive. Depending on that computer’s BIOS, you may have to set its BIOS to allow booting from USB first, or change the boot order, so the computer actually boots from the USB flash drive and not some other drive. Some BIOSs are less than friendly about this and hide this setting in very strange places, so you may need to experiment some.

  6. Connect Ethernet to your PC and your Ethernet network. If you do not have Ethernet on your PC, you can set up WiFi later as described in Setting up networking and DNS.

  7. When the boot process is finished, log in as user root from the attached keyboard and monitor. For password, see I need root.

  8. Now: wait. UBOS needs to generate a few cryptographic keys before it is ready to use and initialize a few other things on the first boot. That might take a few minutes. To determine whether UBOS ready, execute:

    % systemctl is-system-running

    To speed up the process, generate lots of random activity, such as looking through the file system, and typing lots on the keyboard. You only need to do that once, on the first boot.

    To speed up the key generation process, at the potential loss of some entropy, execute:

    % sudo systemctl start haveged
  9. Check that your PC has acquired an IP address:

    % ip addr

    Make sure you are connected to the internet before attempting to proceed.

  10. Update UBOS to the latest and greatest:

    % sudo ubos-admin update
  11. You are now ready for Setting up your first Site and App.