Comment 1 for bug 1183633

This code looks to be the issue:
    def init_host(self):
        """Initialization for a standalone compute service."""
        self.driver.init_host(host=self.host)
        context = nova.context.get_admin_context()
        instances = self.conductor_api.instance_get_all_by_host(context,
                                                                self.host)

        if CONF.defer_iptables_apply:
            self.driver.filter_defer_apply_on()

        self.init_virt_events()

        try:
            # checking that instance was not already evacuated to other host
            self._destroy_evacuated_instances(context)
            for instance in instances:
                self._init_instance(context, instance)
        finally:
            if CONF.defer_iptables_apply:
                self.driver.filter_defer_apply_off()

It tries to bring up all non-evacuated instances, but _init_instance is throwing rather than catching.