For orchestra, must the public keys be copied to the nodes before 'juju bootstrap' is run for the first time?
David, the nodes don't exist before bootstrap is run. Orchestra configures cobbler to install the nodes from scratch, and then start juju. This is done so that juju charms that are deployed can start with a base, clean system. Its been discussed that we may want to make it easier to take control of an existing machine with juju, but right now that is not how it works.
juju bootstrap basically does this with orchestra:
Note that you can override the ssh authorized keys path to use. It will normally use ~/.ssh/id_rsa.pub or ~/.ssh/id_dsa.pub. You can also set it with 'authorized-keys-path' in environments.yaml. You can also insert actual keys to override all of that with 'authorized-keys'.