+ # take first link between switches by default
+ if isinstance(next_node, OVSSwitch):
+ switch_inport_nr = self.DCNetwork_graph[current_hop][next_hop][0]['dst_port_nr']
+ current_hop = next_hop
+
+ return "path {2} between {0} and {1}".format(
+ vnf_src_name, vnf_dst_name, cmd)
+
+ def setChain(self, vnf_src_name, vnf_dst_name,
+ vnf_src_interface=None, vnf_dst_interface=None, **kwargs):
+ """
+ Chain 2 vnf interfaces together by installing the flowrules in the switches along their path.
+ Currently the path is found using the default networkx shortest path function.
+ Each chain gets a unique vlan id , so different chains wil not interfere.
+
+ :param vnf_src_name: vnf name (string)
+ :param vnf_dst_name: vnf name (string)
+ :param vnf_src_interface: source interface name (string)
+ :param vnf_dst_interface: destination interface name (string)
+ :param cmd: 'add-flow' (default) to add a chain, 'del-flows' to remove a chain
+ :param cookie: cookie for the installed flowrules (can be used later as identifier for a set of installed chains)
+ :param match: custom match entry to be added to the flowrules (default: only in_port and vlan tag)
+ :param priority: custom flowrule priority
+ :param monitor: boolean to indicate whether this chain is a monitoring chain
+ :param tag: vlan tag to be used for this chain (pre-defined or new one if none is specified)
+ :param skip_vlan_tag: boolean to indicate if a vlan tag should be appointed to this flow or not
+ :param path: custom path between the two VNFs (list of switches)
+ :return: output log string
+ """
+
+ # special procedure for monitoring flows
+ if kwargs.get('monitor'):
+
+ # check if chain already exists
+ found_chains = [chain_dict for chain_dict in self.installed_chains if
+ (chain_dict['vnf_src_name'] == vnf_src_name and
+ chain_dict['vnf_src_interface'] == vnf_src_interface and
+ chain_dict['vnf_dst_name'] == vnf_dst_name and
+ chain_dict['vnf_dst_interface'] == vnf_dst_interface)]
+
+ if len(found_chains) > 0:
+ # this chain exists, so need an extra monitoring flow
+ # assume only 1 chain per vnf/interface pair
+ LOG.debug('*** installing monitoring chain on top of pre-defined chain from {0}:{1} -> {2}:{3}'.
+ format(vnf_src_name, vnf_src_interface, vnf_dst_name, vnf_dst_interface))
+ tag = found_chains[0]['tag']
+ ret = self._addMonitorFlow(vnf_src_name, vnf_dst_name, vnf_src_interface, vnf_dst_interface,
+ tag=tag, table_id=0, **kwargs)
+ return ret
+ else:
+ # no chain existing (or E-LAN) -> install normal chain
+ LOG.warning('*** installing monitoring chain without pre-defined NSD chain from {0}:{1} -> {2}:{3}'.
+ format(vnf_src_name, vnf_src_interface, vnf_dst_name, vnf_dst_interface))
+ pass
+
+ cmd = kwargs.get('cmd', 'add-flow')
+ if cmd == 'add-flow' or cmd == 'del-flows':
+ ret = self._chainAddFlow(
+ vnf_src_name, vnf_dst_name, vnf_src_interface, vnf_dst_interface, **kwargs)
+ if kwargs.get('bidirectional'):
+ if kwargs.get('path') is not None:
+ kwargs['path'] = list(reversed(kwargs.get('path')))
+ ret = ret + '\n' + \
+ self._chainAddFlow(
+ vnf_dst_name, vnf_src_name, vnf_dst_interface, vnf_src_interface, **kwargs)
+
+ else:
+ ret = "Command unknown"
+
+ return ret
+
+ def _chainAddFlow(self, vnf_src_name, vnf_dst_name,
+ vnf_src_interface=None, vnf_dst_interface=None, **kwargs):
+
+ src_sw = None
+ src_sw_inport_nr = 0
+ src_sw_inport_name = None
+ dst_sw = None
+ dst_sw_outport_nr = 0
+ dst_sw_outport_name = None
+
+ LOG.debug("call chainAddFlow vnf_src_name=%r, vnf_src_interface=%r, vnf_dst_name=%r, vnf_dst_interface=%r",
+ vnf_src_name, vnf_src_interface, vnf_dst_name, vnf_dst_interface)
+
+ # check if port is specified (vnf:port)
+ if vnf_src_interface is None:
+ # take first interface by default
+ connected_sw = self.DCNetwork_graph.neighbors(vnf_src_name)[0]
+ link_dict = self.DCNetwork_graph[vnf_src_name][connected_sw]
+ vnf_src_interface = link_dict[0]['src_port_id']
+
+ for connected_sw in self.DCNetwork_graph.neighbors(vnf_src_name):
+ link_dict = self.DCNetwork_graph[vnf_src_name][connected_sw]
+ for link in link_dict:
+ if (link_dict[link]['src_port_id'] == vnf_src_interface or
+ link_dict[link]['src_port_name'] == vnf_src_interface): # Fix: we might also get interface names, e.g, from a son-emu-cli call
+ # found the right link and connected switch
+ src_sw = connected_sw
+ src_sw_inport_nr = link_dict[link]['dst_port_nr']
+ src_sw_inport_name = link_dict[link]['dst_port_name']
+ break
+
+ if vnf_dst_interface is None:
+ # take first interface by default
+ connected_sw = self.DCNetwork_graph.neighbors(vnf_dst_name)[0]
+ link_dict = self.DCNetwork_graph[connected_sw][vnf_dst_name]
+ vnf_dst_interface = link_dict[0]['dst_port_id']
+
+ vnf_dst_name = vnf_dst_name.split(':')[0]
+ for connected_sw in self.DCNetwork_graph.neighbors(vnf_dst_name):
+ link_dict = self.DCNetwork_graph[connected_sw][vnf_dst_name]
+ for link in link_dict:
+ if link_dict[link]['dst_port_id'] == vnf_dst_interface or \
+ link_dict[link]['dst_port_name'] == vnf_dst_interface: # Fix: we might also get interface names, e.g, from a son-emu-cli call
+ # found the right link and connected switch
+ dst_sw = connected_sw
+ dst_sw_outport_nr = link_dict[link]['src_port_nr']
+ dst_sw_outport_name = link_dict[link]['src_port_name']
+ break
+
+ path = kwargs.get('path')
+ if path is None:
+ # get shortest path
+ try:
+ # returns the first found shortest path
+ # if all shortest paths are wanted, use: all_shortest_paths
+ path = nx.shortest_path(
+ self.DCNetwork_graph, src_sw, dst_sw, weight=kwargs.get('weight'))
+ except BaseException:
+ LOG.exception("No path could be found between {0} and {1} using src_sw={2} and dst_sw={3}".format(
+ vnf_src_name, vnf_dst_name, src_sw, dst_sw))
+ LOG.debug("Graph nodes: %r" % self.DCNetwork_graph.nodes())
+ LOG.debug("Graph edges: %r" % self.DCNetwork_graph.edges())
+ for e, v in self.DCNetwork_graph.edges():
+ LOG.debug("%r" % self.DCNetwork_graph[e][v])
+ return "No path could be found between {0} and {1}".format(
+ vnf_src_name, vnf_dst_name)
+
+ LOG.debug("Creating path between {0} and {1}: {2}".format(
+ vnf_src_name, vnf_dst_name, path))