一、安装轻量级网络仿真工具Mininet

  • 克隆github上的Mininet源
git clone https://github.com/mininet/mininet

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  • 选择默认全部安装
cd mininet
 ./util/install.sh -a

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二、用字符命令搭建如下拓扑，要求写出命令

  • 拓扑
    image.png
  • 命令
sudo mn --topo=linear,3
  • 结果
    image.png

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  • 拓扑
    image.png
  • 命令
sudo mn --topo=tree,depth=2,fanout=3
  • 结果
    image.png

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三、利用可视化工具搭建如下拓扑，并要求支持OpenFlow 1.0 1.1 1.2 1.3，设置h1（10.0.0.10）、h2（10.0.0.11）、h3（10.0.0.12），拓扑搭建完成后使用命令验证主机ip，查看拓扑端口连接情况。

  • 拓扑
    image.png
  • 结果

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四、利用Python脚本完成如下图所示的一个Fat-tree型的拓扑（交换机和主机名需与图中一致，即s1s6，h1h8，并且链路正确，请给出Mininet相关截图）

  • 代码
#!/usr/bin/python
#创建网络拓扑
"""Custom topology example
Adding the 'topos' dict with a key/value pair to generate our newly defined
topology enables one to pass in '--topo=mytopo' from the command line.
"""
 
from mininet.topo import Topo
from mininet.net import Mininet
from mininet.node import RemoteController,CPULimitedHost
from mininet.link import TCLink
from mininet.util import dumpNodeConnections
 
class MyTopo( Topo ):
    "Simple topology example."
 
    def __init__( self ):
        "Create custom topo."
 
        # Initialize topology
        Topo.__init__( self )
        L1 = 2
        L2 = L1 * 2 
        c = []
        a = []
          
        # add core ovs  
        for i in range( L1 ):
                sw = self.addSwitch( 's{}'.format( i + 1 ) )
                c.append( sw )
    
        # add aggregation ovs
        for i in range( L2 ):
                sw = self.addSwitch( 's{}'.format( L1 + i + 1 ) )
                a.append( sw )
    
 
        # add links between core and aggregation ovs
        for i in range( L1 ):
                sw1 = c[i]
                for sw2 in a[i/2::L1/2]:
                # self.addLink(sw2, sw1, bw=10, delay='5ms', loss=10, max_queue_size=1000, use_htb=True)
			            self.addLink( sw2, sw1 )
 
 
        #add hosts and its links with edge ovs
        count = 1
        for sw1 in a:
                for i in range(2):
                	host = self.addHost( 'h{}'.format( count ) )
                	self.addLink( sw1, host )
                	count += 1
topos = { 'mytopo': ( lambda: MyTopo() ) }
  • 结果
    image.png