实验 3:Mininet 实验——测量路径的损耗率

一、实验目的

在实验 2 的基础上进一步熟悉 Mininet 自定义拓扑脚本,以及与损耗率相关的设

定;初步了解 Mininet 安装时自带的 POX 控制器脚本编写,测试路径损耗率。

二、实验步骤

1.实验环境

安装了 Ubuntu 18.04.5 Desktop amd64 的虚拟机

2.实验过程

(1)新建并编辑 pox 脚本 flowstat.py:

#!/usr/bin/python
# Copyright 2012 William Yu
# wyu@ateneo.edu
#
# This file is part of POX.
#
# POX is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# POX is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with POX. If not, see <http://www.gnu.org/licenses/>.
#
"""
This is a demonstration file created to show how to obtain flow 
and port statistics from OpenFlow 1.0-enabled switches. The flow
statistics handler contains a summary of web-only traffic.
"""

# standard includes

from pox.core import core

from pox.lib.util import dpidToStr

import pox.openflow.libopenflow_01 as of

from pox.lib.addresses import IPAddr, EthAddr

 

# include as part of the betta branch

from pox.openflow.of_json import *

from pox.lib.recoco import Timer

import time

 

log = core.getLogger()

 

src_dpid = 0

dst_dpid = 0

input_pkts = 0

output_pkts = 0

 

def getTheTime():  #fuction to create a timestamp

  flock = time.localtime()

  then = "[%s-%s-%s" %(str(flock.tm_year),str(flock.tm_mon),str(flock.tm_mday))

  

  if int(flock.tm_hour)<10:

    hrs = "0%s" % (str(flock.tm_hour))

  else:

    hrs = str(flock.tm_hour)

  if int(flock.tm_min)<10:

    mins = "0%s" % (str(flock.tm_min))

  else:

    mins = str(flock.tm_min)

  if int(flock.tm_sec)<10:

    secs = "0%s" % (str(flock.tm_sec))

  else:

    secs = str(flock.tm_sec)

  then +="]%s.%s.%s" % (hrs,mins,secs)

  return then

 

# handler for timer function that sends the requests to all the

# switches connected to the controller.

def _timer_func ():

  for connection in core.openflow._connections.values():

    connection.send(of.ofp_stats_request(body=of.ofp_flow_stats_request()))

    connection.send(of.ofp_stats_request(body=of.ofp_port_stats_request()))

  log.debug("Sent %i flow/port stats request(s)", len(core.openflow._connections))

 

# handler to display flow statistics received in JSON format

# structure of event.stats is defined by ofp_flow_stats()

def _handle_flowstats_received (event):

   #stats = flow_stats_to_list(event.stats)

   #log.debug("FlowStatsReceived from %s: %s", dpidToStr(event.connection.dpid), stats)

   global src_dpid, dst_dpid, input_pkts, output_pkts

   #print "src_dpid=", dpidToStr(src_dpid), "dst_dpid=", dpidToStr(dst_dpid)

   for f in event.stats:

     if f.match.dl_type==0x0800 and f.match.nw_dst==IPAddr("192.168.123.2") and f.match.nw_tos==0x64 and event.connection.dpid==src_dpid: 

       #print "input: ", f.byte_count, f.packet_count

       input_pkts = f.packet_count

     if f.match.dl_type==0x0800 and f.match.nw_dst==IPAddr("192.168.123.2") and f.match.nw_tos==0x64 and event.connection.dpid==dst_dpid:

       #print "output: ", f.byte_count, f.packet_count  

       output_pkts = f.packet_count

       if input_pkts !=0:

         print getTheTime(), "Path Loss Rate =", (input_pkts-output_pkts)*1.0/input_pkts*100, "%"

 

# handler to display port statistics received in JSON format

def _handle_portstats_received (event):

   #print "\n<<<STATS-REPLY: Return PORT stats for Switch", event.connection.dpid,"at ",getTheTime()

   #for f in event.stats:

      #if int(f.port_no)<65534:

        #print "   PortNo:", f.port_no, " Fwd's Pkts:", f.tx_packets, " Fwd's Bytes:", f.tx_bytes, " Rc'd Pkts:", f.rx_packets, " Rc's Bytes:", f.rx_bytes

        #print "   PortNo:", f.port_no,  " TxDrop:", f.tx_dropped, " RxDrop:", f.rx_dropped, " TxErr:", f.tx_errors, " RxErr:", f.rx_errors, " CRC:", f.rx_crc_err, " Coll:", f.collisions 

  stats = flow_stats_to_list(event.stats)

  log.debug("PortStatsReceived from %s: %s", dpidToStr(event.connection.dpid), stats)

 

def _handle_ConnectionUp (event):

  global src_dpid, dst_dpid

  print "ConnectionUp: ", dpidToStr(event.connection.dpid)

  for m in event.connection.features.ports:

    if m.name == "s0-eth0":

      src_dpid = event.connection.dpid

    elif m.name == "s1-eth0":

      dst_dpid = event.connection.dpid

 

  msg = of.ofp_flow_mod()

  msg.priority =1

  msg.idle_timeout = 0

  msg.match.in_port =1

  msg.actions.append(of.ofp_action_output(port = of.OFPP_ALL))

  event.connection.send(msg)

 

  msg = of.ofp_flow_mod()

  msg.priority =1

  msg.idle_timeout = 0

  msg.match.in_port =2

  msg.actions.append(of.ofp_action_output(port = of.OFPP_ALL))

  event.connection.send(msg)

 

  msg = of.ofp_flow_mod()

  msg.priority =10

  msg.idle_timeout = 0

  msg.hard_timeout = 0

  msg.match.dl_type = 0x0800

  msg.match.nw_tos = 0x64

  msg.match.in_port=1

  msg.match.nw_dst = "192.168.123.2"

  msg.actions.append(of.ofp_action_output(port = 2))

  event.connection.send(msg)

 

  msg = of.ofp_flow_mod()

  msg.priority =10

  msg.idle_timeout = 0

  msg.hard_timeout = 0

  msg.match.dl_type = 0x0800

  msg.match.nw_tos = 0x64

  msg.match.nw_dst = "192.168.123.1"

  msg.actions.append(of.ofp_action_output(port = 1))

  event.connection.send(msg)

    

# main functiont to launch the module

def launch ():

  # attach handsers to listners

  core.openflow.addListenerByName("FlowStatsReceived", 

    _handle_flowstats_received) 

  core.openflow.addListenerByName("PortStatsReceived", 

    _handle_portstats_received) 

  core.openflow.addListenerByName("ConnectionUp", _handle_ConnectionUp)

 

  # timer set to execute every five seconds

  Timer(1, _timer_func, recurring=True)

(2)编辑 Mininet 脚本 mymininet3.py :
#!/usr/bin/python

 

from mininet.net import Mininet

from mininet.node import Node

from mininet.link import TCLink

from mininet.log import  setLogLevel, info

from threading import Timer

from mininet.util import quietRun

from time import sleep

 

def myNet(cname='controller', cargs='-v ptcp:'):

    "Create network from scratch using Open vSwitch."

    info( "*** Creating nodes\n" )

    controller = Node( 'c0', inNamespace=False )

    switch = Node( 's0', inNamespace=False )

    switch1 = Node( 's1', inNamespace=False )

    h0 = Node( 'h0' )

    h1 = Node( 'h1' )

    

    info( "*** Creating links\n" )

    linkopts0=dict(bw=100, delay='1ms', loss=0)

    linkopts1=dict(bw=100, delay='1ms', loss=0)

    link0=TCLink( h0, switch, **linkopts0)

    link1 = TCLink( switch, switch1, **linkopts1)     

    link2 = TCLink( h1, switch1, **linkopts0)

    #print link0.intf1, link0.intf2

    link0.intf2.setMAC("0:0:0:0:0:1")

    link1.intf1.setMAC("0:0:0:0:0:2")

    link1.intf2.setMAC("0:1:0:0:0:1") 

    link2.intf2.setMAC("0:1:0:0:0:2")

 

    info( "*** Configuring hosts\n" )

    h0.setIP( '192.168.123.1/24' )

    h1.setIP( '192.168.123.2/24' )

       

    info( "*** Starting network using Open vSwitch\n" )

    switch.cmd( 'ovs-vsctl del-br dp0' )

    switch.cmd( 'ovs-vsctl add-br dp0' )

    switch1.cmd( 'ovs-vsctl del-br dp1' )

    switch1.cmd( 'ovs-vsctl add-br dp1' )

 

    controller.cmd( cname + ' ' + cargs + '&' )     

    for intf in switch.intfs.values():

        print intf

        print switch.cmd( 'ovs-vsctl add-port dp0 %s' % intf )

    for intf in switch1.intfs.values():

        print intf

        print switch1.cmd( 'ovs-vsctl add-port dp1 %s' % intf )

   

    # Note: controller and switch are in root namespace, and we

    # can connect via loopback interface

    switch.cmd( 'ovs-vsctl set-controller dp0 tcp:127.0.0.1:6633' )

    switch1.cmd( 'ovs-vsctl set-controller dp1 tcp:127.0.0.1:6633' )

  

    info( '*** Waiting for switch to connect to controller' )

    while 'is_connected' not in quietRun( 'ovs-vsctl show' ):

        sleep( 1 )

        info( '.' )

    info( '\n' )

 

    #info( "*** Running test\n" )

    h0.cmdPrint( 'ping -Q 0x64 -c 20 ' + h1.IP() )

    

    sleep( 1 ) 

    info( "*** Stopping network\n" )

    controller.cmd( 'kill %' + cname )

    switch.cmd( 'ovs-vsctl del-br dp0' )

    switch.deleteIntfs()

    switch1.cmd( 'ovs-vsctl del-br dp1' )

    switch1.deleteIntfs()

    info( '\n' )

 

if __name__ == '__main__':

    setLogLevel( 'info' )

    info( '*** Scratch network demo (kernel datapath)\n' )

    Mininet.init()

    myNet()

(3)运行结果:
loss=0
图片替换文本 图片替换文本
loss=10
图片替换文本 图片替换文本
posted @ 2020-09-21 18:02  hell56l  阅读(139)  评论(0编辑  收藏  举报