From the documentation on installing to disk: https://coreos.com/os/docs/latest/installing-to-disk.html
This doesn't work:
#cloud-config
passwd:
users:
- name: core
ssh_authorized_keys:
- ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDGdByTgSVHq...
After digging around and finding this: https://coreos.com/os/docs/latest/cloud-config.html
This works:
#cloud-config
ssh_authorized_keys:
- ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDGdByTgSVHq...