path: root/testcases/testcase.py

# Copyright 2015-2016 Intel Corporation.
#
# 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.
"""TestCase base class
"""

from collections import OrderedDict
import copy
import csv
import logging
import math
import os
import re
import time
import subprocess

from conf import settings as S
from conf import get_test_param
import core.component_factory as component_factory
from core.loader import Loader
from core.results.results_constants import ResultsConstants
from tools import tasks
from tools import hugepages
from tools import functions
from tools.pkt_gen.trafficgen.trafficgenhelper import TRAFFIC_DEFAULTS


class TestCase(object):
    """TestCase base class

    In this basic form runs RFC2544 throughput test
    """
    def __init__(self, cfg):
        """Pull out fields from test config

        :param cfg: A dictionary of string-value pairs describing the test
            configuration. Both the key and values strings use well-known
            values.
        :param results_dir: Where the csv formatted results are written.
        """
        self._testcase_start_time = time.time()
        self._hugepages_mounted = False
        self._traffic_ctl = None
        self._vnf_ctl = None
        self._vswitch_ctl = None
        self._collector = None
        self._loadgen = None
        self._output_file = None
        self._tc_results = None
        self._settings_original = {}
        self._settings_paths_modified = False
        self._testcast_run_time = None

        self._update_settings('VSWITCH', cfg.get('vSwitch', S.getValue('VSWITCH')))
        self._update_settings('VNF', cfg.get('VNF', S.getValue('VNF')))
        self._update_settings('TRAFFICGEN', cfg.get('Trafficgen', S.getValue('TRAFFICGEN')))
        self._update_settings('TEST_PARAMS', cfg.get('Parameters', S.getValue('TEST_PARAMS')))

        # update global settings
        functions.settings_update_paths()
        guest_loopback = get_test_param('guest_loopback', None)
        if guest_loopback:
            # we can put just one item, it'll be expanded automatically for all VMs
            self._update_settings('GUEST_LOOPBACK', [guest_loopback])

        # set test parameters; CLI options take precedence to testcase settings
        self._logger = logging.getLogger(__name__)
        self.name = cfg['Name']
        self.desc = cfg.get('Description', 'No description given.')
        self.test = cfg.get('TestSteps', None)

        bidirectional = cfg.get('biDirectional', TRAFFIC_DEFAULTS['bidir'])
        bidirectional = get_test_param('bidirectional', bidirectional)
        if not isinstance(bidirectional, str):
            raise TypeError(
                'Bi-dir value must be of type string in testcase configuration')
        bidirectional = bidirectional.title()  # Keep things consistent

        traffic_type = cfg.get('Traffic Type', TRAFFIC_DEFAULTS['traffic_type'])
        traffic_type = get_test_param('traffic_type', traffic_type)

        framerate = cfg.get('iLoad', TRAFFIC_DEFAULTS['frame_rate'])
        framerate = get_test_param('iload', framerate)

        self.deployment = cfg['Deployment']
        self._frame_mod = cfg.get('Frame Modification', None)

        self._tunnel_type = None
        self._tunnel_operation = None

        if self.deployment == 'op2p':
            self._tunnel_operation = cfg['Tunnel Operation']

            if 'Tunnel Type' in cfg:
                self._tunnel_type = cfg['Tunnel Type']
                self._tunnel_type = get_test_param('tunnel_type',
                                                   self._tunnel_type)

        # read configuration of streams; CLI parameter takes precedence to
        # testcase definition
        multistream = cfg.get('MultiStream', TRAFFIC_DEFAULTS['multistream'])
        multistream = get_test_param('multistream', multistream)
        stream_type = cfg.get('Stream Type', TRAFFIC_DEFAULTS['stream_type'])
        stream_type = get_test_param('stream_type', stream_type)
        pre_installed_flows = cfg.get('Pre-installed Flows', TRAFFIC_DEFAULTS['pre_installed_flows'])
        pre_installed_flows = get_test_param('pre-installed_flows', pre_installed_flows)

        # check if test requires background load and which generator it uses
        self._load_cfg = cfg.get('Load', None)
        if self._load_cfg and 'tool' in self._load_cfg:
            self._loadgen = self._load_cfg['tool']
        else:
            # background load is not requested, so use dummy implementation
            self._loadgen = "Dummy"

        if self._frame_mod:
            self._frame_mod = self._frame_mod.lower()
        self._results_dir = S.getValue('RESULTS_PATH')

        # set traffic details, so they can be passed to vswitch and traffic ctls
        self._traffic = copy.deepcopy(TRAFFIC_DEFAULTS)
        self._traffic.update({'traffic_type': traffic_type,
                              'flow_type': cfg.get('Flow Type', TRAFFIC_DEFAULTS['flow_type']),
                              'bidir': bidirectional,
                              'tunnel_type': self._tunnel_type,
                              'multistream': int(multistream),
                              'stream_type': stream_type,
                              'pre_installed_flows' : pre_installed_flows,
                              'frame_rate': int(framerate)})

        # Packet Forwarding mode
        self._vswitch_none = 'none' == S.getValue('VSWITCH').strip().lower()

        # trafficgen configuration required for tests of tunneling protocols
        if self.deployment == "op2p":
            self._traffic['l2'].update({'srcmac':
                                        S.getValue('TRAFFICGEN_PORT1_MAC'),
                                        'dstmac':
                                        S.getValue('TRAFFICGEN_PORT2_MAC')})

            self._traffic['l3'].update({'srcip':
                                        S.getValue('TRAFFICGEN_PORT1_IP'),
                                        'dstip':
                                        S.getValue('TRAFFICGEN_PORT2_IP')})

            if self._tunnel_operation == "decapsulation":
                self._traffic['l2'] = S.getValue(self._tunnel_type.upper() + '_FRAME_L2')
                self._traffic['l3'] = S.getValue(self._tunnel_type.upper() + '_FRAME_L3')
                self._traffic['l4'] = S.getValue(self._tunnel_type.upper() + '_FRAME_L4')
        elif S.getValue('NICS')[0]['type'] == 'vf' or S.getValue('NICS')[1]['type'] == 'vf':
            mac1 = S.getValue('NICS')[0]['mac']
            mac2 = S.getValue('NICS')[1]['mac']
            if mac1 and mac2:
                self._traffic['l2'].update({'srcmac': mac2, 'dstmac': mac1})
            else:
                self._logger.debug("MAC addresses can not be read")

    def run_initialize(self):
        """ Prepare test execution environment
        """
        self._logger.debug(self.name)

        # mount hugepages if needed
        self._mount_hugepages()

        self._logger.debug("Controllers:")
        loader = Loader()
        self._traffic_ctl = component_factory.create_traffic(
            self._traffic['traffic_type'],
            loader.get_trafficgen_class())

        self._vnf_ctl = component_factory.create_vnf(
            self.deployment,
            loader.get_vnf_class())

        # verify enough hugepages are free to run the testcase
        if not self._check_for_enough_hugepages():
            raise RuntimeError('Not enough hugepages free to run test.')

        # perform guest related handling
        if self._vnf_ctl.get_vnfs_number():
            # copy sources of l2 forwarding tools into VM shared dir if needed
            self._copy_fwd_tools_for_all_guests()

            # in case of multi VM in parallel, set the number of streams to the number of VMs
            if self.deployment.startswith('pvpv'):
                # for each VM NIC pair we need an unique stream
                streams = 0
                for vm_nic in S.getValue('GUEST_NICS_NR')[:self._vnf_ctl.get_vnfs_number()]:
                    streams += int(vm_nic / 2) if vm_nic > 1 else 1
                self._logger.debug("VMs with parallel connection were detected. "
                                   "Thus Number of streams was set to %s", streams)
                self._traffic.update({'multistream': streams})

            # OVS Vanilla requires guest VM MAC address and IPs to work
            if 'linux_bridge' in S.getValue('GUEST_LOOPBACK'):
                self._traffic['l2'].update({'srcmac': S.getValue('VANILLA_TGEN_PORT1_MAC'),
                                            'dstmac': S.getValue('VANILLA_TGEN_PORT2_MAC')})
                self._traffic['l3'].update({'srcip': S.getValue('VANILLA_TGEN_PORT1_IP'),
                                            'dstip': S.getValue('VANILLA_TGEN_PORT2_IP')})

        if self._vswitch_none:
            self._vswitch_ctl = component_factory.create_pktfwd(
                self.deployment,
                loader.get_pktfwd_class())
        else:
            self._vswitch_ctl = component_factory.create_vswitch(
                self.deployment,
                loader.get_vswitch_class(),
                self._traffic,
                self._tunnel_operation)

        self._collector = component_factory.create_collector(
            loader.get_collector_class(),
            self._results_dir, self.name)
        self._loadgen = component_factory.create_loadgen(
            self._loadgen,
            self._load_cfg)

        self._output_file = os.path.join(self._results_dir, "result_" + self.name +
                                         "_" + self.deployment + ".csv")

        self._logger.debug("Setup:")

    def run_finalize(self):
        """ Tear down test execution environment and record test results
        """
        # umount hugepages if mounted
        self._umount_hugepages()

        # restore original settings
        S.load_from_dict(self._settings_original)

        # cleanup any namespaces created
        if os.path.isdir('/tmp/namespaces'):
            import tools.namespace
            namespace_list = os.listdir('/tmp/namespaces')
            if len(namespace_list):
                self._logger.info('Cleaning up namespaces')
            for name in namespace_list:
                tools.namespace.delete_namespace(name)
            os.rmdir('/tmp/namespaces')
        # cleanup any veth ports created
        if os.path.isdir('/tmp/veth'):
            import tools.veth
            veth_list = os.listdir('/tmp/veth')
            if len(veth_list):
                self._logger.info('Cleaning up veth ports')
            for eth in veth_list:
                port1, port2 = eth.split('-')
                tools.veth.del_veth_port(port1, port2)
            os.rmdir('/tmp/veth')

    def run_report(self):
        """ Report test results
        """
        self._logger.debug("self._collector Results:")
        self._collector.print_results()

        if S.getValue('mode') != 'trafficgen-off':
            self._logger.debug("Traffic Results:")
            self._traffic_ctl.print_results()

            self._tc_results = self._append_results(self._traffic_ctl.get_results())
            TestCase.write_result_to_file(self._tc_results, self._output_file)

    def run(self):
        """Run the test

        All setup and teardown through controllers is included.
        """
        # prepare test execution environment
        self.run_initialize()

        with self._vswitch_ctl, self._loadgen:
            with self._vnf_ctl, self._collector:
                if not self._vswitch_none:
                    self._add_flows()

                # run traffic generator if requested, otherwise wait for manual termination
                if S.getValue('mode') == 'trafficgen-off':
                    time.sleep(2)
                    self._logger.debug("All is set. Please run traffic generator manually.")
                    input(os.linesep + "Press Enter to terminate vswitchperf..." + os.linesep + os.linesep)
                else:
                    if S.getValue('mode') == 'trafficgen-pause':
                        time.sleep(2)
                        true_vals = ('yes', 'y', 'ye', None)
                        while True:
                            choice = input(os.linesep + 'Transmission paused, should'
                                           ' transmission be resumed? ' + os.linesep).lower()
                            if not choice or choice not in true_vals:
                                print('Please respond with \'yes\' or \'y\' ', end='')
                            else:
                                break
                    with self._traffic_ctl:
                        self._traffic_ctl.send_traffic(self._traffic)

                    # dump vswitch flows before they are affected by VNF termination
                    if not self._vswitch_none:
                        self._vswitch_ctl.dump_vswitch_flows()

        # tear down test execution environment and log results
        self.run_finalize()

        self._testcase_run_time = time.strftime("%H:%M:%S",
                                  time.gmtime(time.time() - self._testcase_start_time))
        logging.info("Testcase execution time: " + self._testcase_run_time)
        # report test results
        self.run_report()

    def _update_settings(self, param, value):
        """ Check value of given configuration parameter
        In case that new value is different, then testcase
        specific settings is updated and original value stored

        :param param: Name of parameter inside settings
        :param value: Disired parameter value
        """
        orig_value = S.getValue(param)
        if orig_value != value:
            self._settings_original[param] = orig_value
            S.setValue(param, value)

    def _append_results(self, results):
        """
        Method appends mandatory Test Case results to list of dictionaries.

        :param results: list of dictionaries which contains results from
                traffic generator.

        :returns: modified list of dictionaries.
        """
        for item in results:
            item[ResultsConstants.ID] = self.name
            item[ResultsConstants.DEPLOYMENT] = self.deployment
            item[ResultsConstants.TRAFFIC_TYPE] = self._traffic['l3']['proto']
            item[ResultsConstants.TEST_RUN_TIME] = self._testcase_run_time
            if self._traffic['multistream']:
                item[ResultsConstants.SCAL_STREAM_COUNT] = self._traffic['multistream']
                item[ResultsConstants.SCAL_STREAM_TYPE] = self._traffic['stream_type']
                item[ResultsConstants.SCAL_PRE_INSTALLED_FLOWS] = self._traffic['pre_installed_flows']
            if self._vnf_ctl.get_vnfs_number():
                item[ResultsConstants.GUEST_LOOPBACK] = ' '.join(S.getValue('GUEST_LOOPBACK'))
            if self._tunnel_type:
                item[ResultsConstants.TUNNEL_TYPE] = self._tunnel_type
        return results

    def _copy_fwd_tools_for_all_guests(self):
        """Copy dpdk and l2fwd code to GUEST_SHARE_DIR[s] based on selected deployment.
        """
        # consider only VNFs involved in the test
        for guest_dir in set(S.getValue('GUEST_SHARE_DIR')[:self._vnf_ctl.get_vnfs_number()]):
            self._copy_fwd_tools_for_guest(guest_dir)

    def _copy_fwd_tools_for_guest(self, guest_dir):
        """Copy dpdk and l2fwd code to GUEST_SHARE_DIR of VM

        :param index: Index of VM starting from 1 (i.e. 1st VM has index 1)
        """
        # remove shared dir if it exists to avoid issues with file consistency
        if os.path.exists(guest_dir):
            tasks.run_task(['rm', '-f', '-r', guest_dir], self._logger,
                           'Removing content of shared directory...', True)

        # directory to share files between host and guest
        os.makedirs(guest_dir)

        # copy sources into shared dir only if neccessary
        guest_loopback = set(S.getValue('GUEST_LOOPBACK'))
        if 'testpmd' in guest_loopback:
            try:
                # exclude whole .git/ subdirectory and all o-files;
                # It is assumed, that the same RTE_TARGET is used in both host
                # and VMs; This simplification significantly speeds up testpmd
                # build. If we will need a different RTE_TARGET in VM,
                # then we have to build whole DPDK from the scratch in VM.
                # In that case we can copy just DPDK sources (e.g. by excluding
                # all items obtained by git status -unormal --porcelain).
                # NOTE: Excluding RTE_TARGET directory won't help on systems,
                # where DPDK is built for multiple targets (e.g. for gcc & icc)
                exclude = []
                exclude.append(r'--exclude=.git/')
                exclude.append(r'--exclude=*.o')
                tasks.run_task(['rsync', '-a', '-r', '-l'] + exclude +
                               [os.path.join(S.getValue('TOOLS')['dpdk_src'], ''),
                                os.path.join(guest_dir, 'DPDK')],
                               self._logger,
                               'Copying DPDK to shared directory...',
                               True)
            except subprocess.CalledProcessError:
                self._logger.error('Unable to copy DPDK to shared directory')
                raise
        if 'l2fwd' in guest_loopback:
            try:
                tasks.run_task(['rsync', '-a', '-r', '-l',
                                os.path.join(S.getValue('ROOT_DIR'), 'src/l2fwd/'),
                                os.path.join(guest_dir, 'l2fwd')],
                               self._logger,
                               'Copying l2fwd to shared directory...',
                               True)
            except subprocess.CalledProcessError:
                self._logger.error('Unable to copy l2fwd to shared directory')
                raise

    def _mount_hugepages(self):
        """Mount hugepages if usage of DPDK or Qemu is detected
        """
        # hugepages are needed by DPDK and Qemu
        if not self._hugepages_mounted and \
            (self.deployment.count('v') or \
             S.getValue('VSWITCH').lower().count('dpdk') or \
             self._vswitch_none or \
             self.test and 'vnf' in [step[0][0:3] for step in self.test]):
            hugepages.mount_hugepages()
            self._hugepages_mounted = True

    def _umount_hugepages(self):
        """Umount hugepages if they were mounted before
        """
        if self._hugepages_mounted:
            hugepages.umount_hugepages()
            self._hugepages_mounted = False

    def _check_for_enough_hugepages(self):
        """Check to make sure enough hugepages are free to satisfy the
        test environment.
        """
        hugepages_needed = 0
        hugepage_size = hugepages.get_hugepage_size()
        # get hugepage amounts per guest involved in the test
        for guest in range(self._vnf_ctl.get_vnfs_number()):
            hugepages_needed += math.ceil((int(S.getValue(
                'GUEST_MEMORY')[guest]) * 1000) / hugepage_size)

        # get hugepage amounts for each socket on dpdk
        sock0_mem, sock1_mem = 0, 0
        if S.getValue('VSWITCH').lower().count('dpdk'):
            # the import below needs to remain here and not put into the module
            # imports because of an exception due to settings not yet loaded
            from vswitches import ovs_dpdk_vhost
            if ovs_dpdk_vhost.OvsDpdkVhost.old_dpdk_config():
                match = re.search(
                    r'-socket-mem\s+(\d+),(\d+)',
                    ''.join(S.getValue('VSWITCHD_DPDK_ARGS')))
                if match:
                    sock0_mem, sock1_mem = (int(match.group(1)) * 1024 / hugepage_size,
                                            int(match.group(2)) * 1024 / hugepage_size)
                else:
                    logging.info(
                        'Could not parse socket memory config in dpdk params.')
            else:
                sock0_mem, sock1_mem = (
                    S.getValue(
                        'VSWITCHD_DPDK_CONFIG')['dpdk-socket-mem'].split(','))
                sock0_mem, sock1_mem = (int(sock0_mem) * 1024 / hugepage_size,
                                        int(sock1_mem) * 1024 / hugepage_size)

        # If hugepages needed, verify the amounts are free
        if any([hugepages_needed, sock0_mem, sock1_mem]):
            free_hugepages = hugepages.get_free_hugepages()
            if hugepages_needed:
                logging.info('Need %s hugepages free for guests',
                             hugepages_needed)
                result1 = free_hugepages >= hugepages_needed
                free_hugepages -= hugepages_needed
            else:
                result1 = True

            if sock0_mem:
                logging.info('Need %s hugepages free for dpdk socket 0',
                             sock0_mem)
                result2 = hugepages.get_free_hugepages('0') >= sock0_mem
                free_hugepages -= sock0_mem
            else:
                result2 = True

            if sock1_mem:
                logging.info('Need %s hugepages free for dpdk socket 1',
                             sock1_mem)
                result3 = hugepages.get_free_hugepages('1') >= sock1_mem
                free_hugepages -= sock1_mem
            else:
                result3 = True

            logging.info('Need a total of {} total hugepages'.format(
                hugepages_needed + sock1_mem + sock0_mem))

            # The only drawback here is sometimes dpdk doesn't release
            # its hugepages on a test failure. This could cause a test
            # to fail when dpdk would be OK to start because it will just
            # use the previously allocated hugepages.
            result4 = True if free_hugepages >= 0 else False

            return all([result1, result2, result3, result4])
        else:
            return True

    @staticmethod
    def write_result_to_file(results, output):
        """Write list of dictionaries to a CSV file.

        Each element on list will create separate row in output file.
        If output file already exists, data will be appended at the end,
        otherwise it will be created.

        :param results: list of dictionaries.
        :param output: path to output file.
        """
        with open(output, 'a') as csvfile:

            logging.info("Write results to file: " + output)
            fieldnames = TestCase._get_unique_keys(results)

            writer = csv.DictWriter(csvfile, fieldnames)

            if not csvfile.tell():  # file is now empty
                writer.writeheader()

            for result in results:
                writer.writerow(result)

    @staticmethod
    def _get_unique_keys(list_of_dicts):
        """Gets unique key values as ordered list of strings in given dicts

        :param list_of_dicts: list of dictionaries.

        :returns: list of unique keys(strings).
        """
        result = OrderedDict()
        for item in list_of_dicts:
            for key in item.keys():
                result[key] = ''

        return list(result.keys())

    def _add_flows(self):
        """Add flows to the vswitch
        """
        vswitch = self._vswitch_ctl.get_vswitch()
        # TODO BOM 15-08-07 the frame mod code assumes that the
        # physical ports are ports 1 & 2. The actual numbers
        # need to be retrived from the vSwitch and the metadata value
        # updated accordingly.
        bridge = S.getValue('VSWITCH_BRIDGE_NAME')
        if self._frame_mod == "vlan":
            # 0x8100 => VLAN ethertype
            self._logger.debug(" ****   VLAN   ***** ")
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'actions': ['push_vlan:0x8100', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'actions': ['push_vlan:0x8100', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "mpls":
            # 0x8847 => MPLS unicast ethertype
            self._logger.debug(" ****   MPLS  ***** ")
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'actions': ['push_mpls:0x8847', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'actions': ['push_mpls:0x8847', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "mac":
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'actions': ['mod_dl_src:22:22:22:22:22:22',
                                'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'actions': ['mod_dl_src:11:11:11:11:11:11',
                                'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "dscp":
            # DSCP 184d == 0x4E<<2 => 'Expedited Forwarding'
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_tos:184', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_tos:184', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "ttl":
            # 251 and 241 are the highest prime numbers < 255
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_ttl:251', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_ttl:241', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "ip_addr":
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_src:10.10.10.10',
                                'mod_nw_dst:20.20.20.20',
                                'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'dl_type':'0x0800',
                    'actions': ['mod_nw_src:20.20.20.20',
                                'mod_nw_dst:10.10.10.10',
                                'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        elif self._frame_mod == "ip_port":
            # TODO BOM 15-08-27 The traffic generated is assumed
            # to be UDP (nw_proto 17d) which is the default case but
            # we will need to pick up the actual traffic params in use.
            flow = {'table':'2', 'priority':'1000', 'metadata':'2',
                    'dl_type':'0x0800', 'nw_proto':'17',
                    'actions': ['mod_tp_src:44444',
                                'mod_tp_dst:44444', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
            flow = {'table':'2', 'priority':'1000', 'metadata':'1',
                    'dl_type':'0x0800', 'nw_proto':'17',
                    'actions': ['mod_tp_src:44444',
                                'mod_tp_dst:44444', 'goto_table:3']}
            vswitch.add_flow(bridge, flow)
        else:
            pass