You can inject local files into the instance file system when you launch an instance. Use the --file dst-path=src-path parameter on the nova boot command. You can inject up to five files. For example, you might inject the special_authorized_keysfile file into the instance rather than using the regular ssh key injection. Run the following command: $ nova boot --image ubuntu-cloudimage --flavor 1 --file /root/.ssh/authorized_keys=special_authorized_keysfile