1 實驗目的

熟悉Mininet自定義拓撲腳本的編寫；
掌握使用“ovs-vsctl”命令直接控制Open vSwitch。

2 實驗原理

在SDN環境中，控制器可以通過對交換機下發流表操作來控制交換機的轉發行為。在本實驗中，使用Mininet基於python的腳本，調用“ovs-vsctl”命令直接控制Open vSwitch。

3 實驗任務

本實驗在基於Mininet腳本的不同拓撲環境下使用OpenDaylight控制交換機行為。任務一：一台交換機兩台主機，從1端口進入的數據流轉發到2端口，從2端口進入的數據流轉發到1端口；任務二：兩台交換機兩台主機，主機0連接交換機0，主機1連接交換機1，交換機0連接交換機1，數據轉發端口同任務一；任務三：與任務二類似，但是在創建link的時候，設置帶寬、延遲以及丟包率。

任務一：一台交換機兩台主機，實現從1端口進入的數據流轉發到2端口，從2端口進入的數據流轉發到1端口。

還是那個流程：

打開mininet文件夾——創建mymininet1.py——編輯腳本保存——改為可執行——清內存——開發者模式內打開

 1 # !/usr/bin/python 
 2 from mininet.net import Mininet
 3 from mininet.node import Node
 4 from mininet.link import Link
 5 from mininet.log import setLogLevel, info
 6 from mininet.util import quietRun
 7 # 調用Mininet相關模塊
 8  
 9 from time import sleep
10 # 調用sleep模塊 
11  
12 def scratchNet( cname='controller', cargs='-v ptcp:' ):
13     "Create network from scratch using Open vSwitch."
14  
15     # 創建網絡節點其中有兩個主機，一個交換機，一個控制器
16     info( "*** Creating nodes\n" )
17     controller = Node( 'c0', inNamespace=False )
18     switch0 = Node( 's0', inNamespace=False )
19     h0 = Node( 'h0' )
20     h1 = Node( 'h1' )
21  
22     # 創建網絡連接，分別是h0-s0和h1-s0
23     info( "*** Creating links\n" )
24     Link( h0, switch0 )
25     Link( h1, switch0 )
26  
27     # 設置主機的IP地址，然后再診斷的同時打印出string化的h0h1
28     info( "*** Configuring hosts\n" )
29     h0.setIP( '192.168.123.1/24' )
30     h1.setIP( '192.168.123.2/24' )
31     info( str( h0 ) + '\n' )
32     info( str( h1 ) + '\n' )
33  
34     # 開啟控制器和s0的鏈路
35     info( "*** Starting network using Open vSwitch\n" )
36     controller.cmd( cname + ' ' + cargs + '&' )
37     switch0.cmd( 'ovs-vsctl del-br dp0' )
38     switch0.cmd( 'ovs-vsctl add-br dp0' )
39  
40     # 在交換機的信息庫里面依次打出信息
41     for intf in switch0.intfs.values():
42         print intf
43         print switch0.cmd( 'ovs-vsctl add-port dp0 %s' % intf )
44     switch0.cmd( 'ovs-vsctl set-controller dp0 tcp:10.0.0.8:6633' )
45     switch0.cmd( 'ovs-ofctl add-flow dp0 \"in_port=1 actions=output:2\"' )
46     switch0.cmd( 'ovs-ofctl add-flow dp0 \"in_port=2 actions=output:1\"' )
47  
48     # 等待連接的小程序
49     info( '*** Waiting for switch to connect to controller' )
50     while 'is_connected' not in quietRun( 'ovs-vsctl show' ):
51         sleep( 1 )
52         info( '.' )
53     info( '\n' )
54  
55     # 兩個互ping6次
56     info( "*** Running test\n" )
57     h0.cmdPrint( 'ping -c6 ' + h1.IP() )
58     h1.cmdPrint( 'ping -c6 ' + h0.IP() )
59  
60     # 關閉這個網絡
61     info( "*** Stopping network\n" )
62     controller.cmd( 'kill %' + cname )
63     switch0.cmd( 'ovs-vsctl del-br dp0' )
64     switch0.deleteIntfs()
65     info( '\n' )
66  
67 # 主函數部分，設置打印等級，還有調用以上的一些函數
68 if __name__ == '__main__':
69     setLogLevel( 'info' )
70     info( '*** Scratch network demo (kernel datapath)\n' )
71     Mininet.init()
72     scratchNet()

任務二：兩台交換機兩台主機，主機0連接交換機0，主機1連接交換機1，交換機0連接交換機1，數據轉發端口要求同任務一。

和前者的腳本大同小異，這里就解釋mymininet1.py沒有的，print switch0.cmd( 'ovs-ofctl show dp0' )意思就是打出關於s0的信息

 
             1 #!/usr/bin/python  
from mininet.net import Mininet
from mininet.node import Node
from mininet.link import Link
from mininet.log import setLogLevel, info
from mininet.util import quietRun

from time import sleep

def scratchNet( cname='controller', cargs='-v ptcp:' ):
   "Create network from scratch using Open vSwitch."

   info( "*** Creating nodes\n" )
   controller = Node( 'c0', inNamespace=False )
   switch0 = Node( 's0', inNamespace=False )
   switch1 = Node( 's1', inNamespace=False )
   h0 = Node( 'h0' )
   h1 = Node( 'h1' )

   info( "*** Creating links\n" )
   Link( h0, switch0 )
   Link( h1, switch1 )
   Link( switch0, switch1 )

   info( "*** Configuring hosts\n" )
   h0.setIP( '192.168.123.1/24' )
   h1.setIP( '192.168.123.2/24' )
   info( str( h0 ) + '\n' )
   info( str( h1 ) + '\n' )

   info( "*** Starting network using Open vSwitch\n" )
   controller.cmd( cname + ' ' + cargs + '&' )
   switch0.cmd( 'ovs-vsctl del-br dp0' )
   switch0.cmd( 'ovs-vsctl add-br dp0' )
   switch1.cmd( 'ovs-vsctl del-br dp1' )
   switch1.cmd( 'ovs-vsctl add-br dp1' )


   for intf in switch0.intfs.values():
       print intf
       print switch0.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 )

   switch0.cmd( 'ovs-vsctl set-controller dp0 tcp:10.0.0.8:6633' )
   switch1.cmd( 'ovs-vsctl set-controller dp1 tcp: 10.0.0.8:6633' )
   switch0.cmd( 'ovs-ofctl add-flow dp0 \"in_port=1 actions=output:2\"' )
   switch0.cmd( 'ovs-ofctl add-flow dp0 \"in_port=2 actions=output:1\"' )
   switch1.cmd( 'ovs-ofctl add-flow dp1 \"in_port=1 actions=output:2\"' )
   switch1.cmd( 'ovs-ofctl add-flow dp1 \"in_port=2 actions=output:1\"' )


   info( '*** Waiting for switch to connect to controller' )
   while 'is_connected' not in quietRun( 'ovs-vsctl show' ):
       sleep( 1 )
       info( '.' )
   info( '\n' )
   print switch0.cmd( 'ovs-ofctl show dp0' )
   print switch1.cmd( 'ovs-ofctl show dp1' )


   info( "*** Running test\n" )
   h0.cmdPrint( 'ping -c3 ' + h1.IP() )
   h1.cmdPrint( 'ping -c3 ' + h0.IP() )

   info( "*** Stopping network\n" )
   controller.cmd( 'kill %' + cname )
   switch0.cmd( 'ovs-vsctl del-br dp0' )
   switch0.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()
   scratchNet() 
           

任務三：與任務二類似，但是在創建link的時候，設置帶寬、延遲以及丟包率。

 1 #!/usr/bin/python 
 2 from mininet.net import Mininet
 3 from mininet.node import Node
 4 from mininet.link import TCLink
 5 from mininet.log import setLogLevel, info
 6 from mininet.util import quietRun
 7  
 8 from time import sleep
 9  
10 def scratchNet( cname='controller', cargs='-v ptcp:' ):
11     "Create network from scratch using Open vSwitch."
12  
13     info( "*** Creating nodes\n" )
14     controller = Node( 'c0', inNamespace=False )
15     switch0 = Node( 's0', inNamespace=False )
16     switch1 = Node( 's1', inNamespace=False )
17     h0 = Node( 'h0' )
18     h1 = Node( 'h1' )
19  
20     info( "*** Creating links\n" )
21  
22     linkopts0=dict(bw=10)
23     linkopts1=dict(bw=10, delay='5ms', loss=10)
24     TCLink( h0, switch0,**linkopts0)
25     TCLink( h1, switch1,**linkopts0)
26     TCLink( switch0, switch1,**linkopts1)
27  
28  
29     info( "*** Configuring hosts\n" )
30     h0.setIP( '192.168.123.1/24' )
31     h1.setIP( '192.168.123.2/24' )
32     info( str( h0 ) + '\n' )
33     info( str( h1 ) + '\n' )
34  
35     info( "*** Starting network using Open vSwitch\n" )
36     controller.cmd( cname + ' ' + cargs + '&' )
37     switch0.cmd( 'ovs-vsctl del-br dp0' )
38     switch0.cmd( 'ovs-vsctl add-br dp0' )
39     switch1.cmd( 'ovs-vsctl del-br dp1' )
40     switch1.cmd( 'ovs-vsctl add-br dp1' )
41  
42  
43     for intf in switch0.intfs.values():
44         print intf
45         print switch0.cmd( 'ovs-vsctl add-port dp0 %s' % intf )
46  
47     for intf in switch1.intfs.values():
48         print intf
49         print switch1.cmd( 'ovs-vsctl add-port dp1 %s' % intf )
50  
51     switch0.cmd( 'ovs-vsctl set-controller dp0 tcp:10.0.0.8:6633' )
52     switch1.cmd( 'ovs-vsctl set-controller dp1 tcp: 10.0.0.8:6633' )
53     switch0.cmd( 'ovs-ofctl add-flow dp0 \"in_port=1 actions=output:2\"' )
54     switch0.cmd( 'ovs-ofctl add-flow dp0 \"in_port=2 actions=output:1\"' )
55     switch1.cmd( 'ovs-ofctl add-flow dp1 \"in_port=1 actions=output:2\"' )
56     switch1.cmd( 'ovs-ofctl add-flow dp1 \"in_port=2 actions=output:1\"' )
57  
58  
59     info( '*** Waiting for switch to connect to controller' )
60     while 'is_connected' not in quietRun( 'ovs-vsctl show' ):
61         sleep( 1 )
62         info( '.' )
63     info( '\n' )
64     print switch0.cmd( 'ovs-ofctl show dp0' )
65     print switch1.cmd( 'ovs-ofctl show dp1' )
66  
67  
68     info( "*** Running test\n" )
69     h0.cmdPrint( 'ping -c3 ' + h1.IP() )
70     h1.cmdPrint( 'ping -c3 ' + h0.IP() )
71  
72     info( "*** Stopping network\n" )
73     controller.cmd( 'kill %' + cname )
74     switch0.cmd( 'ovs-vsctl del-br dp0' )
75     switch0.deleteIntfs()
76     switch1.cmd( 'ovs-vsctl del-br dp1' )
77     switch1.deleteIntfs()
78     info( '\n' )
79  
80 if __name__ == '__main__':
81     setLogLevel( 'info' )
82     info( '*** Scratch network demo (kernel datapath)\n' )
83     Mininet.init()
84     scratchNet()

總結：

1.對ovs加深理解

2.能夠完全看懂腳本

3.需要更深一步了解mininet的模塊的函數

免責聲明！

本站轉載的文章為個人學習借鑒使用，本站對版權不負任何法律責任。如果侵犯了您的隱私權益，請聯系本站郵箱yoyou2525@163.com刪除。

猜您在找 使用Scapy向Mininet交換機注入流量實驗記錄 Mininet 系列實驗（一） Mininet系列實驗（12個實驗） Mininet python代碼創建拓撲、交互式界面創建主機、交換機 Mininet系列實驗（五）：Mininet設置帶寬之簡單性能測試 Mininet系列實驗（二）：Mininet可視化應用 Mininet實驗源碼安裝mininet mininet實驗連接floodlight控制器 H3C5***系列交換機堆疊實驗實驗3 交換機的基本配置