constellation/images/fcos/assembler/README.md

Constellation-OS Assembler

This container image uses coreos assembler as a base (quay.io/coreos-assembler/coreos-assembler) to facilitate a build environment for the Constellation-OS. The root filesystem takes its contents (OSTree) from constellation-fedora-coreos-config. The constellation specific changes are tracked in this repository: https://github.com/edgelesssys/constellation-coreos-assembler And the Constellation-OS Assembler can be pulled from ghcr.io/edgelesssys/constellation-coreos-assembler

Setup

Prerequisites: podman and qemu-kvm are installed, nested virtualization is enabled. Make sure your user is allowed read and write access on /dev/kvm. If the device is not mounted in the container try the following command, and restart the container:

sudo chmod 666 /dev/kvm

Using the Assembler to create a bootable operating system

1. Create the assembler image as described here
2. Source the fcos/.env file to enable the cosa bash alias:

   source fcos/.env
   

3. Set the COORDINATOR_BINARY environment variable to a path of the compiled coordinator binary. It will be mounted in the cosa container and copied into the resulting coreos image.

   COORDINATOR_BINARY="/path/to/coordinator"
   

4. Go into the build folder and initialize cosa:

   cd fcos/build
   cosa init https://github.com/edgelesssys/constellation-fedora-coreos-config
   cosa fetch
   

5. Build the OS image:

   cosa build
   

6. Create an image for a cloud provider

   cosa buildextend-gcp
   cosa buildextend-aws
   cosa buildextend-azure
   [...]
   

Using a locally checked out git repo of the coreos-config during development

Simply set the environment variable COREOS_ASSEMBLER_CONFIG_GIT to the local folder and perform the rest of the steps as usual:

COREOS_ASSEMBLER_CONFIG_GIT=/path/to/constellation-fedora-coreos-config