diff --git a/src/emuvim/dcemulator/net.py b/src/emuvim/dcemulator/net.py
index 0e3882c..ade984f 100755
--- a/src/emuvim/dcemulator/net.py
+++ b/src/emuvim/dcemulator/net.py
@@ -44,6 +44,9 @@
 from emuvim.dcemulator.node import Datacenter, EmulatorCompute
 from emuvim.dcemulator.resourcemodel import ResourceModelRegistrar
 
+LOG = logging.getLogger("dcemulator.net")
+LOG.setLevel(logging.DEBUG)
+
 class DCNetwork(Containernet):
     """
     Wraps the original Mininet/Containernet class and provides
@@ -110,7 +113,7 @@
         dc.net = self  # set reference to network
         self.dcs[label] = dc
         dc.create()  # finally create the data center in our Mininet instance
-        logging.info("added data center: %s" % label)
+        LOG.info("added data center: %s" % label)
         return dc
 
     def addLink(self, node1, node2, **params):
@@ -120,7 +123,7 @@
         """
         assert node1 is not None
         assert node2 is not None
-        logging.debug("addLink: n1=%s n2=%s" % (str(node1), str(node2)))
+        LOG.debug("addLink: n1=%s n2=%s" % (str(node1), str(node2)))
         # ensure type of node1
         if isinstance( node1, basestring ):
             if node1 in self.dcs:
@@ -274,6 +277,14 @@
 
     def _chainAddFlow(self, vnf_src_name, vnf_dst_name, vnf_src_interface=None, vnf_dst_interface=None, **kwargs):
 
+        src_sw = None
+        dst_sw = None
+        src_sw_inport_nr = 0
+        dst_sw_outport_nr = 0
+
+        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
@@ -284,10 +295,10 @@
         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:
+                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']
                     break
 
@@ -301,7 +312,8 @@
         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:
+                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']
@@ -314,10 +326,15 @@
             # 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:
-            logging.info("No path could be found between {0} and {1}".format(vnf_src_name, vnf_dst_name))
+            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)
 
-        logging.info("Path between {0} and {1}: {2}".format(vnf_src_name, vnf_dst_name, path))
+        LOG.info("Path between {0} and {1}: {2}".format(vnf_src_name, vnf_dst_name, path))
 
         current_hop = src_sw
         switch_inport_nr = src_sw_inport_nr
@@ -342,9 +359,9 @@
 
             if next_hop == vnf_dst_name:
                 switch_outport_nr = dst_sw_outport_nr
-                logging.info("end node reached: {0}".format(vnf_dst_name))
+                LOG.info("end node reached: {0}".format(vnf_dst_name))
             elif not isinstance( next_node, OVSSwitch ):
-                logging.info("Next node: {0} is not a switch".format(next_hop))
+                LOG.info("Next node: {0} is not a switch".format(next_hop))
                 return "Next node: {0} is not a switch".format(next_hop)
             else:
                 # take first link between switches by default
@@ -474,7 +491,7 @@
             ofcmd = ''
 
         node.dpctl(cmd, ofcmd)
-        logging.info("{3} in switch: {0} in_port: {1} out_port: {2}".format(node.name, switch_inport_nr,
+        LOG.info("{3} in switch: {0} in_port: {1} out_port: {2}".format(node.name, switch_inport_nr,
                                                                                  switch_outport_nr, cmd))
 
     # start Ryu Openflow controller as Remote Controller for the DCNetwork
@@ -508,7 +525,7 @@
             else:
                 url = self.ryu_REST_api + '/' + str(prefix)
             if data:
-                #logging.info('POST: {0}'.format(str(data)))
+                #LOG.info('POST: {0}'.format(str(data)))
                 req = urllib2.Request(url, str(data))
             else:
                 req = urllib2.Request(url)
@@ -516,8 +533,8 @@
             ret = urllib2.urlopen(req).read()
             return ret
         except:
-            logging.info('error url: {0}'.format(str(url)))
-            if data: logging.info('error POST: {0}'.format(str(data)))
+            LOG.info('error url: {0}'.format(str(url)))
+            if data: LOG.info('error POST: {0}'.format(str(data)))
 
     # need to respect that some match fields must be integers
     # http://ryu.readthedocs.io/en/latest/app/ofctl_rest.html#description-of-match-and-actions
diff --git a/src/emuvim/dcemulator/node.py b/src/emuvim/dcemulator/node.py
index b29d634..aa9fb4a 100755
--- a/src/emuvim/dcemulator/node.py
+++ b/src/emuvim/dcemulator/node.py
@@ -32,7 +32,7 @@
 import time
 import json
 
-LOG = logging.getLogger("dcemulator")
+LOG = logging.getLogger("dcemulator.node")
 LOG.setLevel(logging.DEBUG)
 
 
diff --git a/src/emuvim/examples/sonata_y1_demo_topology_1.py b/src/emuvim/examples/sonata_y1_demo_topology_1.py
index c5c9611..1792f88 100755
--- a/src/emuvim/examples/sonata_y1_demo_topology_1.py
+++ b/src/emuvim/examples/sonata_y1_demo_topology_1.py
@@ -43,7 +43,7 @@
 
 def create_topology1():
     # create topology
-    net = DCNetwork(controller=RemoteController, monitor=False, enable_learning = False)
+    net = DCNetwork(controller=RemoteController, monitor=False, enable_learning=False)
     dc1 = net.addDatacenter("dc1")
     dc2 = net.addDatacenter("dc2")
     s1 = net.addSwitch("s1")
@@ -52,6 +52,7 @@
 
     # add the command line interface endpoint to each DC (REST API)
     rapi1 = RestApiEndpoint("0.0.0.0", 5001)
+    rapi1.connectDCNetwork(net)
     rapi1.connectDatacenter(dc1)
     rapi1.connectDatacenter(dc2)
     # run API endpoint server (in another thread, don't block)