Fix VLAN range of setChain
[osm/vim-emu.git] / src / emuvim / dcemulator / net.py
index 3556535..3eee2e5 100755 (executable)
@@ -1,26 +1,61 @@
 """
-Distributed Cloud Emulator (dcemulator)
-(c) 2015 by Manuel Peuster <manuel.peuster@upb.de>
+Copyright (c) 2015 SONATA-NFV and Paderborn University
+ALL RIGHTS RESERVED.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+Neither the name of the SONATA-NFV [, ANY ADDITIONAL AFFILIATION]
+nor the names of its contributors may be used to endorse or promote
+products derived from this software without specific prior written
+permission.
+
+This work has been performed in the framework of the SONATA project,
+funded by the European Commission under Grant number 671517 through
+the Horizon 2020 and 5G-PPP programmes. The authors would like to
+acknowledge the contributions of their colleagues of the SONATA
+partner consortium (www.sonata-nfv.eu).
 """
 import logging
 
 import site
 import time
 from subprocess import Popen
-import os
 import re
-import urllib2
-from functools import partial
+import requests
+import os
+import json
 
 from mininet.net import Containernet
 from mininet.node import Controller, DefaultController, OVSSwitch, OVSKernelSwitch, Docker, RemoteController
 from mininet.cli import CLI
 from mininet.link import TCLink
+from mininet.clean import cleanup
 import networkx as nx
 from emuvim.dcemulator.monitoring import DCNetworkMonitor
-from emuvim.dcemulator.node import Datacenter, EmulatorCompute
+from emuvim.dcemulator.node import Datacenter, EmulatorCompute, EmulatorExtSAP
 from emuvim.dcemulator.resourcemodel import ResourceModelRegistrar
 
+LOG = logging.getLogger("dcemulator.net")
+LOG.setLevel(logging.DEBUG)
+
+# default CPU period used for cpu percentage-based cfs values (microseconds)
+CPU_PERIOD = 1000000
+
+# default priority setting for added flow-rules
+DEFAULT_PRIORITY = 1000
+# default cookie number for new flow-rules
+DEFAULT_COOKIE = 10
+
 class DCNetwork(Containernet):
     """
     Wraps the original Mininet/Containernet class and provides
@@ -30,7 +65,7 @@ class DCNetwork(Containernet):
     """
 
     def __init__(self, controller=RemoteController, monitor=False,
-                 enable_learning = True,   # in case of RemoteController (Ryu), learning switch behavior can be turned off/on
+                 enable_learning=False, # learning switch behavior of the default ovs switches icw Ryu controller can be turned off/on, needed for E-LAN functionality
                  dc_emulation_max_cpu=1.0,  # fraction of overall CPU time for emulation
                  dc_emulation_max_mem=512,  # emulation max mem in MB
                  **kwargs):
@@ -40,18 +75,36 @@ class DCNetwork(Containernet):
         :param kwargs: path through for Mininet parameters
         :return:
         """
+        # members
         self.dcs = {}
+        self.ryu_process = None
+        #list of deployed nsds.E_Lines and E_LANs (uploaded from the dummy gatekeeper)
+        self.deployed_nsds = []
+        self.deployed_elines = []
+        self.deployed_elans = []
+        self.installed_chains = []
+
+
+        # always cleanup environment before we start the emulator
+        self.killRyu()
+        cleanup()
 
         # call original Docker.__init__ and setup default controller
         Containernet.__init__(
             self, switch=OVSKernelSwitch, controller=controller, **kwargs)
 
+        # default switch configuration
+        enable_ryu_learning = False
+        if enable_learning :
+            self.failMode = 'standalone'
+            enable_ryu_learning = True
+        else:
+            self.failMode = 'secure'
 
         # Ryu management
-        self.ryu_process = None
         if controller == RemoteController:
             # start Ryu controller
-            self.startRyu(learning_switch=enable_learning)
+            self.startRyu(learning_switch=enable_ryu_learning)
 
         # add the specified controller
         self.addController('c0', controller=controller)
@@ -60,12 +113,13 @@ class DCNetwork(Containernet):
         self.DCNetwork_graph = nx.MultiDiGraph()
 
         # initialize pool of vlan tags to setup the SDN paths
-        self.vlans = range(4096)[::-1]
+        self.vlans = range(1, 4096)[::-1]
 
         # link to Ryu REST_API
-        ryu_ip = '0.0.0.0'
+        ryu_ip = 'localhost'
         ryu_port = '8080'
         self.ryu_REST_api = 'http://{0}:{1}'.format(ryu_ip, ryu_port)
+        self.RyuSession = requests.Session()
 
         # monitoring agent
         if monitor:
@@ -76,6 +130,7 @@ class DCNetwork(Containernet):
         # initialize resource model registrar
         self.rm_registrar = ResourceModelRegistrar(
             dc_emulation_max_cpu, dc_emulation_max_mem)
+        self.cpu_period = CPU_PERIOD
 
     def addDatacenter(self, label, metadata={}, resource_log_path=None):
         """
@@ -87,7 +142,7 @@ class DCNetwork(Containernet):
         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):
@@ -97,7 +152,7 @@ class DCNetwork(Containernet):
         """
         assert node1 is not None
         assert node2 is not None
-        logging.debug("addLink: n1=%s n2=%s" % (str(node1), str(node2)))
+
         # ensure type of node1
         if isinstance( node1, basestring ):
             if node1 in self.dcs:
@@ -153,7 +208,7 @@ class DCNetwork(Containernet):
         edge_attributes = [p for p in params if p in weight_metrics]
         for attr in edge_attributes:
             # if delay: strip ms (need number as weight in graph)
-            match = re.search('([0-9]*\.?[0-9]+)', params[attr])
+            match = re.search('([0-9]*\.?[0-9]+)', str(params[attr]))
             if match:
                 attr_number = match.group(1)
             else:
@@ -175,29 +230,79 @@ class DCNetwork(Containernet):
         attr_dict2.update(attr_dict)
         self.DCNetwork_graph.add_edge(node2.name, node1.name, attr_dict=attr_dict2)
 
+        LOG.debug("addLink: n1={0} intf1={1} -- n2={2} intf2={3}".format(
+            str(node1),node1_port_name, str(node2), node2_port_name))
+
         return link
 
+    def removeLink(self, link=None, node1=None, node2=None):
+        """
+        Remove the link from the Containernet and the networkx graph
+        """
+        if link is not None:
+            node1 = link.intf1.node
+            node2 = link.intf2.node
+        assert node1 is not None
+        assert node2 is not None
+        Containernet.removeLink(self, link=link, node1=node1, node2=node2)
+        # TODO we might decrease the loglevel to debug:
+        try:
+            self.DCNetwork_graph.remove_edge(node2.name, node1.name)
+        except:
+            LOG.warning("%s, %s not found in DCNetwork_graph." % ((node2.name, node1.name)))
+        try:
+            self.DCNetwork_graph.remove_edge(node1.name, node2.name)
+        except:
+            LOG.warning("%s, %s not found in DCNetwork_graph." % ((node1.name, node2.name)))
+
     def addDocker( self, label, **params ):
         """
         Wrapper for addDocker method to use custom container class.
         """
-        self.DCNetwork_graph.add_node(label)
+        self.DCNetwork_graph.add_node(label, type=params.get('type', 'docker'))
         return Containernet.addDocker(self, label, cls=EmulatorCompute, **params)
 
-    def removeDocker( self, label, **params ):
+    def removeDocker( self, label, **params):
         """
         Wrapper for removeDocker method to update graph.
         """
         self.DCNetwork_graph.remove_node(label)
         return Containernet.removeDocker(self, label, **params)
 
+    def addExtSAP(self, sap_name, sap_ip, **params):
+        """
+        Wrapper for addExtSAP method to store SAP  also in graph.
+        """
+        # make sure that 'type' is set
+        params['type'] = params.get('type','sap_ext')
+        self.DCNetwork_graph.add_node(sap_name, type=params['type'])
+        return Containernet.addExtSAP(self, sap_name, sap_ip, **params)
+
+    def removeExtSAP(self, sap_name, **params):
+        """
+        Wrapper for removeExtSAP method to remove SAP  also from graph.
+        """
+        self.DCNetwork_graph.remove_node(sap_name)
+        return Containernet.removeExtSAP(self, sap_name)
+
     def addSwitch( self, name, add_to_graph=True, **params ):
         """
         Wrapper for addSwitch method to store switch also in graph.
         """
+
+        # add this switch to the global topology overview
         if add_to_graph:
-            self.DCNetwork_graph.add_node(name)
-        return Containernet.addSwitch(self, name, protocols='OpenFlow10,OpenFlow12,OpenFlow13', **params)
+            self.DCNetwork_graph.add_node(name, type=params.get('type','switch'))
+
+        # set the learning switch behavior
+        if 'failMode' in params :
+            failMode = params['failMode']
+        else :
+            failMode = self.failMode
+
+        s = Containernet.addSwitch(self, name, protocols='OpenFlow10,OpenFlow12,OpenFlow13', failMode=failMode, **params)
+
+        return s
 
     def getAllContainers(self):
         """
@@ -224,32 +329,77 @@ class DCNetwork(Containernet):
         Containernet.stop(self)
 
         # stop Ryu controller
-        self.stopRyu()
+        self.killRyu()
 
 
     def CLI(self):
         CLI(self)
 
-    # to remove chain do setChain( src, dst, cmd='del-flows')
-    def setChain(self, vnf_src_name, vnf_dst_name, vnf_src_interface=None, vnf_dst_interface=None, **kwargs):
-        cmd = kwargs.get('cmd')
-        if cmd == 'add-flow':
-            ret = self._chainAddFlow(vnf_src_name, vnf_dst_name, vnf_src_interface, vnf_dst_interface, **kwargs)
-            if kwargs.get('bidirectional'):
-                return ret +'\n' + self._chainAddFlow(vnf_dst_name, vnf_src_name, vnf_dst_interface, vnf_src_interface, **kwargs)
-
-        elif cmd == 'del-flows':  # TODO: del-flow to be implemented
-            ret = self._chainAddFlow(vnf_src_name, vnf_dst_name, vnf_src_interface, vnf_dst_interface, **kwargs)
-            if kwargs.get('bidirectional'):
-                return ret + '\n' + self._chainAddFlow(vnf_dst_name, vnf_src_name, vnf_dst_interface, vnf_src_interface, **kwargs)
+    def setLAN(self, vnf_list):
+        """
+        setup an E-LAN network by assigning the same VLAN tag to each DC interface of the VNFs in the E-LAN
 
-        else:
-            return "Command unknown"
+        :param vnf_list: names of the VNFs in this E-LAN  [{name:,interface:},...]
+        :return:
+        """
+        src_sw = None
+        src_sw_inport_nr = 0
+        src_sw_inport_name = None
+
+        # get a vlan tag for this E-LAN
+        vlan = self.vlans.pop()
+
+        for vnf in vnf_list:
+            vnf_src_name = vnf['name']
+            vnf_src_interface = vnf['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
+
+            # set the tag on the dc switch interface
+            LOG.debug('set E-LAN: vnf name: {0} interface: {1} tag: {2}'.format(vnf_src_name, vnf_src_interface,vlan))
+            switch_node = self.getNodeByName(src_sw)
+            self._set_vlan_tag(switch_node, src_sw_inport_name, vlan)
+
+    def _addMonitorFlow(self, vnf_src_name, vnf_dst_name, vnf_src_interface=None, vnf_dst_interface=None,
+                       tag=None, **kwargs):
+        """
+        Add a monitoring flow entry that adds a special flowentry/counter at the begin or end of a chain.
+        So this monitoring flowrule exists on top of a previously defined chain rule and uses the same vlan tag/routing.
+        :param vnf_src_name:
+        :param vnf_dst_name:
+        :param vnf_src_interface:
+        :param vnf_dst_interface:
+        :param tag: vlan tag to be used for this chain (same tag as existing chain)
+        :param monitor_placement: 'tx' or 'rx' indicating to place the extra flowentry resp. at the beginning or end of the chain
+        :return:
+        """
 
+        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
 
-    def _chainAddFlow(self, vnf_src_name, vnf_dst_name, vnf_src_interface=None, vnf_dst_interface=None, **kwargs):
+        LOG.debug("call AddMonitorFlow 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)
 
-        # TODO: this needs to be cleaned up
         #check if port is specified (vnf:port)
         if vnf_src_interface is None:
             # take first interface by default
@@ -260,11 +410,12 @@ class DCNetwork(Containernet):
         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']
+                    src_sw_inport_name = link_dict[link]['dst_port_name']
                     break
 
         if vnf_dst_interface is None:
@@ -277,12 +428,16 @@ class DCNetwork(Containernet):
         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']
+                    dst_sw_outport_name = link_dict[link]['src_port_name']
                     break
 
+        if not tag >= 0:
+            LOG.exception('tag not valid: {0}'.format(tag))
 
         # get shortest path
         try:
@@ -290,21 +445,22 @@ class DCNetwork(Containernet):
             # 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
 
-        # choose free vlan if path contains more than 1 switch
         cmd = kwargs.get('cmd')
-        vlan = None
-        if cmd == 'add-flow':
-            if len(path) > 1:
-                vlan = self.vlans.pop()
 
+        #iterate through the path to install the flow-entries
         for i in range(0,len(path)):
             current_node = self.getNodeByName(current_hop)
 
@@ -318,9 +474,9 @@ class DCNetwork(Containernet):
 
             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
@@ -329,10 +485,224 @@ class DCNetwork(Containernet):
 
 
            # set of entry via ovs-ofctl
+            if isinstance( current_node, OVSSwitch ):
+                kwargs['vlan'] = tag
+                kwargs['path'] = path
+                kwargs['current_hop'] = current_hop
+                kwargs['switch_inport_name'] = src_sw_inport_name
+                kwargs['switch_outport_name'] = dst_sw_outport_name
+                kwargs['skip_vlan_tag'] = True
+                kwargs['pathindex'] = i
+
+                monitor_placement = kwargs.get('monitor_placement').strip()
+                # put monitor flow at the dst switch
+                insert_flow = False
+                if monitor_placement == 'tx' and path.index(current_hop) == 0:  # first node:
+                    insert_flow = True
+                # put monitoring flow at the src switch
+                elif monitor_placement == 'rx' and path.index(current_hop) == len(path) - 1:  # last node:
+                    insert_flow = True
+                elif monitor_placement not in ['rx', 'tx']:
+                    LOG.exception('invalid monitor command: {0}'.format(monitor_placement))
+
+
+                if self.controller == RemoteController and insert_flow:
+                    ## set flow entry via ryu rest api
+                    self._set_flow_entry_ryu_rest(current_node, switch_inport_nr, switch_outport_nr, **kwargs)
+                    break
+                elif insert_flow:
+                    ## set flow entry via ovs-ofctl
+                    self._set_flow_entry_dpctl(current_node, switch_inport_nr, switch_outport_nr, **kwargs)
+                    break
+
+            # 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:
+                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.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
+
+        # choose free vlan
+        cmd = kwargs.get('cmd')
+        vlan = None
+        if cmd == 'add-flow':
+            if kwargs.get('tag'):
+                # use pre-defined tag
+                vlan = kwargs.get('tag')
+            else:
+                vlan = self.vlans.pop()
+
+        # store the used vlan tag to identify this chain
+        if not kwargs.get('monitor'):
+            chain_dict = {}
+            chain_dict['vnf_src_name'] = vnf_src_name
+            chain_dict['vnf_dst_name'] = vnf_dst_name
+            chain_dict['vnf_src_interface'] = vnf_src_interface
+            chain_dict['vnf_dst_interface'] = vnf_dst_interface
+            chain_dict['tag'] = vlan
+            self.installed_chains.append(chain_dict)
+
+        #iterate through the path to install the flow-entries
+        for i in range(0,len(path)):
+            current_node = self.getNodeByName(current_hop)
+
+            if i < len(path) - 1:
+                next_hop = path[i + 1]
+            else:
+                # last switch reached
+                next_hop = vnf_dst_name
+
+            next_node = self.getNodeByName(next_hop)
+
+            if next_hop == vnf_dst_name:
+                switch_outport_nr = dst_sw_outport_nr
+                LOG.info("end node reached: {0}".format(vnf_dst_name))
+            elif not isinstance( next_node, OVSSwitch ):
+                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
+                index_edge_out = 0
+                switch_outport_nr = self.DCNetwork_graph[current_hop][next_hop][index_edge_out]['src_port_nr']
+
+
+           # set OpenFlow entry
             if isinstance( current_node, OVSSwitch ):
                 kwargs['vlan'] = vlan
                 kwargs['path'] = path
                 kwargs['current_hop'] = current_hop
+                kwargs['switch_inport_name'] = src_sw_inport_name
+                kwargs['switch_outport_name'] = dst_sw_outport_name
+                kwargs['pathindex'] = i
 
                 if self.controller == RemoteController:
                     ## set flow entry via ryu rest api
@@ -341,14 +711,20 @@ class DCNetwork(Containernet):
                     ## set flow entry via ovs-ofctl
                     self._set_flow_entry_dpctl(current_node, switch_inport_nr, switch_outport_nr, **kwargs)
 
-
-
             # 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)
+        flow_options = {
+            'priority':kwargs.get('priority', DEFAULT_PRIORITY),
+            'cookie':kwargs.get('cookie', DEFAULT_COOKIE),
+            'vlan':kwargs['vlan'],
+            'path':kwargs['path'],
+            'match_input':kwargs.get('match')
+        }
+        flow_options_str = json.dumps(flow_options, indent=1)
+        return "success: {2} between {0} and {1} with options: {3}".format(vnf_src_name, vnf_dst_name, cmd, flow_options_str)
 
     def _set_flow_entry_ryu_rest(self, node, switch_inport_nr, switch_outport_nr, **kwargs):
         match = 'in_port=%s' % switch_inport_nr
@@ -357,8 +733,16 @@ class DCNetwork(Containernet):
         match_input = kwargs.get('match')
         cmd = kwargs.get('cmd')
         path = kwargs.get('path')
-        current_hop = kwargs.get('current_hop')
+        index = kwargs.get('pathindex')
+
         vlan = kwargs.get('vlan')
+        priority = kwargs.get('priority', DEFAULT_PRIORITY)
+        # flag to not set the ovs port vlan tag
+        skip_vlan_tag = kwargs.get('skip_vlan_tag')
+        # table id to put this flowentry
+        table_id = kwargs.get('table_id')
+        if not table_id:
+            table_id = 0
 
         s = ','
         if match_input:
@@ -369,7 +753,10 @@ class DCNetwork(Containernet):
 
         if cookie:
             flow['cookie'] = int(cookie)
+        if priority:
+            flow['priority'] = int(priority)
 
+        flow['table_id'] = table_id
 
         flow['actions'] = []
 
@@ -378,23 +765,39 @@ class DCNetwork(Containernet):
         if cmd == 'add-flow':
             prefix = 'stats/flowentry/add'
             if vlan != None:
-                if path.index(current_hop) == 0:  # first node
-                    action = {}
-                    action['type'] = 'PUSH_VLAN'  # Push a new VLAN tag if a input frame is non-VLAN-tagged
-                    action['ethertype'] = 33024   # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
-                    flow['actions'].append(action)
-                    action = {}
-                    action['type'] = 'SET_FIELD'
-                    action['field'] = 'vlan_vid'
-                    action['value'] = vlan
-                    flow['actions'].append(action)
-                elif path.index(current_hop) == len(path) - 1:  # last node
-                    match += ',dl_vlan=%s' % vlan
-                    action = {}
-                    action['type'] = 'POP_VLAN'
-                    flow['actions'].append(action)
+                if index == 0:  # first node
+                    # set vlan tag in ovs instance (to isolate E-LANs)
+                    if not skip_vlan_tag:
+                        in_port_name = kwargs.get('switch_inport_name')
+                        self._set_vlan_tag(node, in_port_name, vlan)
+                    # set vlan push action if more than 1 switch in the path
+                    if len(path) > 1:
+                        action = {}
+                        action['type'] = 'PUSH_VLAN'  # Push a new VLAN tag if a input frame is non-VLAN-tagged
+                        action['ethertype'] = 33024   # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
+                        flow['actions'].append(action)
+                        action = {}
+                        action['type'] = 'SET_FIELD'
+                        action['field'] = 'vlan_vid'
+                        # ryu expects the field to be masked
+                        action['value'] = vlan | 0x1000
+                        flow['actions'].append(action)
+
+                elif index == len(path) - 1:  # last node
+                    # set vlan tag in ovs instance (to isolate E-LANs)
+                    if not skip_vlan_tag:
+                        out_port_name = kwargs.get('switch_outport_name')
+                        self._set_vlan_tag(node, out_port_name, vlan)
+                    # set vlan pop action if more than 1 switch in the path
+                    if len(path) > 1:
+                        match += ',dl_vlan=%s' % vlan
+                        action = {}
+                        action['type'] = 'POP_VLAN'
+                        flow['actions'].append(action)
+
                 else:  # middle nodes
                     match += ',dl_vlan=%s' % vlan
+
             # output action must come last
             action = {}
             action['type'] = 'OUTPUT'
@@ -404,9 +807,8 @@ class DCNetwork(Containernet):
         elif cmd == 'del-flows':
             prefix = 'stats/flowentry/delete'
 
-            # if cookie is given, only delete flows by cookie
-            # do not specify other match -> also other cookies can be matched
             if cookie:
+                # TODO: add cookie_mask as argument
                 flow['cookie_mask'] = int('0xffffffffffffffff', 16)  # need full mask to match complete cookie
 
             action = {}
@@ -417,14 +819,19 @@ class DCNetwork(Containernet):
         flow['match'] = self._parse_match(match)
         self.ryu_REST(prefix, data=flow)
 
+    def _set_vlan_tag(self, node, switch_port, tag):
+        node.vsctl('set', 'port {0} tag={1}'.format(switch_port,tag))
+        LOG.debug("set vlan in switch: {0} in_port: {1} vlan tag: {2}".format(node.name, switch_port, tag))
+
     def _set_flow_entry_dpctl(self, node, switch_inport_nr, switch_outport_nr, **kwargs):
+
         match = 'in_port=%s' % switch_inport_nr
 
         cookie = kwargs.get('cookie')
         match_input = kwargs.get('match')
         cmd = kwargs.get('cmd')
         path = kwargs.get('path')
-        current_hop = kwargs.get('current_hop')
+        index = kwargs.get('pathindex')
         vlan = kwargs.get('vlan')
 
         s = ','
@@ -436,10 +843,10 @@ class DCNetwork(Containernet):
         if cmd == 'add-flow':
             action = 'action=%s' % switch_outport_nr
             if vlan != None:
-                if path.index(current_hop) == 0:  # first node
+                if index == 0: # first node
                     action = ('action=mod_vlan_vid:%s' % vlan) + (',output=%s' % switch_outport_nr)
                     match = '-O OpenFlow13 ' + match
-                elif path.index(current_hop) == len(path) - 1:  # last node
+                elif index == len(path) - 1:  # last node
                     match += ',dl_vlan=%s' % vlan
                     action = 'action=strip_vlan,output=%s' % switch_outport_nr
                 else:  # middle nodes
@@ -451,14 +858,18 @@ class DCNetwork(Containernet):
             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
     def startRyu(self, learning_switch=True):
         # start Ryu controller with rest-API
         python_install_path = site.getsitepackages()[0]
-        ryu_path = python_install_path + '/ryu/app/simple_switch_13.py'
+        # ryu default learning switch
+        #ryu_path = python_install_path + '/ryu/app/simple_switch_13.py'
+        #custom learning switch that installs a default NORMAL action in the ovs switches
+        dir_path = os.path.dirname(os.path.realpath(__file__))
+        ryu_path = dir_path + '/son_emu_simple_switch_13.py'
         ryu_path2 = python_install_path + '/ryu/app/ofctl_rest.py'
         # change the default Openflow controller port to 6653 (official IANA-assigned port number), as used by Mininet
         # Ryu still uses 6633 as default
@@ -468,34 +879,56 @@ class DCNetwork(Containernet):
         FNULL = open("/tmp/ryu.log", 'w')
         if learning_switch:
             self.ryu_process = Popen([ryu_cmd, ryu_path, ryu_path2, ryu_option, ryu_of_port], stdout=FNULL, stderr=FNULL)
+            LOG.debug('starting ryu-controller with {0}'.format(ryu_path))
+            LOG.debug('starting ryu-controller with {0}'.format(ryu_path2))
         else:
-            # no learning switch
+            # no learning switch, but with rest api
             self.ryu_process = Popen([ryu_cmd, ryu_path2, ryu_option, ryu_of_port], stdout=FNULL, stderr=FNULL)
+            LOG.debug('starting ryu-controller with {0}'.format(ryu_path2))
         time.sleep(1)
 
-    def stopRyu(self):
+    def killRyu(self):
+        """
+        Stop the Ryu controller that might be started by son-emu.
+        :return:
+        """
+        # try it nicely
         if self.ryu_process is not None:
             self.ryu_process.terminate()
             self.ryu_process.kill()
+        # ensure its death ;-)
+        Popen(['pkill', '-f', 'ryu-manager'])
 
     def ryu_REST(self, prefix, dpid=None, data=None):
-        if data: logging.info('log POST: {0}'.format(str(data)))
-        try:
-            if dpid:
-                url = self.ryu_REST_api + '/' + str(prefix) + '/' + str(dpid)
-            else:
-                url = self.ryu_REST_api + '/' + str(prefix)
-            if data:
-                #logging.info('POST: {0}'.format(str(data)))
-                req = urllib2.Request(url, str(data))
-            else:
-                req = urllib2.Request(url)
 
-            ret = urllib2.urlopen(req).read()
+        if dpid:
+            url = self.ryu_REST_api + '/' + str(prefix) + '/' + str(dpid)
+        else:
+            url = self.ryu_REST_api + '/' + str(prefix)
+        if data:
+            req = self.RyuSession.post(url, json=data)
+        else:
+            req = self.RyuSession.get(url)
+
+
+        # do extra logging if status code is not 200 (OK)
+        if req.status_code is not requests.codes.ok:
+            logging.info(
+                'type {0}  encoding: {1} text: {2} headers: {3} history: {4}'.format(req.headers['content-type'],
+                                                                                     req.encoding, req.text,
+                                                                                     req.headers, req.history))
+            LOG.info('url: {0}'.format(str(url)))
+            if data: LOG.info('POST: {0}'.format(str(data)))
+            LOG.info('status: {0} reason: {1}'.format(req.status_code, req.reason))
+
+
+        if 'json' in req.headers['content-type']:
+            ret = req.json()
             return ret
-        except:
-            logging.info('error url: {0}'.format(str(url)))
-            if data: logging.info('error POST: {0}'.format(str(data)))
+
+        ret = req.text.rstrip()
+        return ret
+
 
     # 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
@@ -513,3 +946,21 @@ class DCNetwork(Containernet):
                 dict.update({match[0]:m2})
         return dict
 
+    def find_connected_dc_interface(self, vnf_src_name, vnf_src_interface=None):
+
+        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']
+                    return src_sw_inport_name