+ chain_start = ingress_ports[0]
+ chain_rest = ingress_ports[1:]
+
+ source_port_to_chain_start = []
+ for flow_classifier_id in self.flow_classifiers:
+ flow_classifier = compute.find_flow_classifier_by_name_or_id(flow_classifier_id)
+ if flow_classifier:
+ port = compute.find_port_by_name_or_id(flow_classifier.logical_source_port)
+ source_port_to_chain_start.append((port, chain_start))
+
+ chain = source_port_to_chain_start + zip(egress_ports, chain_rest)