Comment 6 for bug 2012391

Nova metadata gets the domain from the dhcp_domain parameter in nova.conf, on charmed openstack the value of juju config neutron-api dns-domain, gets passed to dhcp_domain in nova.conf.

Here's the code on yoga which generates the hostname for the nova metadata:

    def _get_hostname(self):
        # TODO(stephenfin): At some point in the future, we may wish to
        # retrieve this information from neutron.
        if CONF.api.dhcp_domain:
            return '.'.join([self.instance.hostname, CONF.api.dhcp_domain])

        return self.instance.hostname

Maybe that's a RFE to make nova metadata receive the hostname from the neutron dns_assignment attribute.