实验2：Open vSwitch虚拟交换机实践

实验报告

1.1 /home/用户名/学号/lab2/目录下执行ovs-vsctl show命令

1.2 p0和p1连通性测试的执行结果截图

2.1 /home/用户名/学号/lab2/目录下开启Mininet CLI并执行pingall命令的截图

2.2 上述目录下查看OVS流表的命令结果截图

2.3 wireshark抓包截图

进阶要求

• 代码：

from mininet.net import Mininet
from mininet.node import Controller, RemoteController, OVSController
from mininet.node import CPULimitedHost, Host, Node
from mininet.node import OVSKernelSwitch, UserSwitch
from mininet.node import IVSSwitch
from mininet.cli import CLI
from mininet.log import setLogLevel, info
from mininet.link import TCLink, Intf
from subprocess import call
​
def mynetwork():
    
    net = Mininet( topo=None,build=False,ipBase='192.168.0.0/24')
​
    info( '*** Adding controller\n' )
    c0=net.addController(name='c0',
                      controller=Controller,
                      protocol='tcp',
                      port=6633)
​
    info( '*** Add switches\n')
    s1 = net.addSwitch('s1', cls=OVSKernelSwitch)
    s2 = net.addSwitch('s2', cls=OVSKernelSwitch)
    
​
    info( '*** Add hosts\n')
    h1 = net.addHost('h1', cls=Host, ip='192.168.0.1', defaultRoute=None)
    h2 = net.addHost('h2', cls=Host, ip='192.168.0.2', defaultRoute=None)
    h3 = net.addHost('h3', cls=Host, ip='192.168.0.3', defaultRoute=None)
    h4 = net.addHost('h4', cls=Host, ip='192.168.0.4', defaultRoute=None)
    
    
    info( '*** Add links\n')
    net.addLink(h1, s1, 1, 1)
    net.addLink(s1, h2, 2, 1)
    net.addLink(s1, s2, 3, 3)
    net.addLink(s2, h3, 1, 1)
    net.addLink(s2, h4, 2, 1)
​
    info( '*** Starting network\n')
    net.build()
    info( '*** Starting controllers\n')
    for controller in net.controllers:
        controller.start()
​
    info( '*** Starting switches\n')
    net.get('s1').start([c0])
    net.get('s2').start([c0])
​
    info( '*** Post configure switches and hosts\n')
​
    s1.cmd('sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,in_port=1,actions=push_vlan:0x8100,set_field:4096-\>vlan_vid,output:3')
    
    s1.cmd('sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,in_port=2,actions=push_vlan:0x8100,set_field:4097-\>vlan_vid,output:3')
    
    s1.cmd('sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,dl_vlan=0,actions=pop_vlan,output:1')
    
    s1.cmd('sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,dl_vlan=1,actions=pop_vlan,output:2')
    
    s2.cmd('sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,in_port=1,actions=push_vlan:0x8100,set_field:4096-\>vlan_vid,output:3')
    
    s2.cmd('sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,in_port=2,actions=push_vlan:0x8100,set_field:4097-\>vlan_vid,output:3')
    
    s2.cmd('sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,dl_vlan=0,actions=pop_vlan,output:1')
    
    s2.cmd('sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,dl_vlan=1,actions=pop_vlan,output:2')
    
​
    CLI(net)
    net.stop()
​
if __name__ == '__main__':
    setLogLevel( 'info' )
    mynetwork()

• pingall
  
• wireshark
  
  

个人总结

总结:这次的实验主要学习了怎么使用Open vSwitch虚拟交换机，相对于上次实验来说会简单一些，但是还是遇到了很多的小bug,比如python代码的异常缩进，后来是通过将代码复制到pycharm上面，才解决了这个问题，还有就是没有添加好主机就开始ping，结果就是返回的不符合预期，后来重做一遍解决。

这次实验也认识了OVS相关的语法，学习了关于topo库的使用，了解了VLAN的知识。
但是还是有很多细小的知识点没有掌握好，自己还存在很多知识缺乏的情况，希望自己再接再厉，认真做好实验。