How to build rancherOS AMIs

What tools do you guys use to build the AMIs? The existing build instructions get me as far as an ISO but it’s not clear to me how to turn that into an AMI. If that piece isn’t open source would you consider releasing it?

To be clear I’m trying to cut AMIs to test v0.4.3-rc2 in our VPC.

Figured it out:

Launch latest rancherOS release as a new instance.
Attach new EBS volume (ex: /dev/xvdf)

Format volume:
sudo system-docker run --privileged -it --entrypoint=/scripts/set-disk-partitions rancher/os:v0.4.3-rc2 /dev/xvdf

Here’s the minimum cloud config:

#cloud-config
rancher:
  cloud_init:
    datasources:
      - ec2

Copy that to /home/rancher on the build instance as cloud-config.yml.

Install:
sudo system-docker run --privileged -it -v /home:/home -v /opt:/opt rancher/os:v0.4.3-rc2 -d /dev/xvdf -t amazon-ebs-hvm -c $(pwd)/cloud-config.yml

Snapshot the volume and create the AMI from it.

Tested and working.

Edit: I haven’t tried running those commands against user docker. It may work as well.