#!/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)
#!/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:127.0.0.1:66‘ )
switch1.cmd( ‘ovs-vsctl set-controller dp1 tcp:127.0.0.1:66‘ )
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()
Ping 默认是每 1 秒钟测一次，ping 的结果会显示一个丢包率，这里的丢包率是根据 ping 不通的次数占总次数的百分比计算得到的。上图中由于一共 ping 了 20次，每次都能通，所以丢包率是 0。观察 pox 侧的实时状态更新平均丢包率为 0，结果符合 Mininet 脚本中设置的损耗率，也有可能出现负值，可以认为没有丢包。
修改代码
info( "*** Creating links\n" )
linkopts0=dict(bw=100, delay=‘1ms‘, loss=0)
linkopts1=dict(bw=100, delay=‘1ms‘, loss=10)
link0=TCLink( h0, switch, **linkopts0)
link1 = TCLink( switch, switch1, **linkopts1)
link2 = TCLink( h1, switch1, **linkopts0)
POX 端重新测试，会发现出现丢包现象，但是实际测量出的丢包率会有浮动，链路的性能总体受到了限制。
重新运行 Mininet 脚本 mymininet3.py，20 秒时间的 ping 过程中有 icmp_seq 为2/4/14/16/19/20 共 6 次 ping 不通，所以丢包率计算为 30%。
原文：https://www.cnblogs.com/zaiyunduan7/p/13709427.html