# SDN第一次上机作业

SDN第一次上机作业

SDN第一次上机作业
1.安装mininet

参考链接：安装参考教程

2.用字符命令生成拓扑，并测试连通性，截图

参考链接：参考教程

3.用可视化界面生成拓扑，并测试连通性，截图

参考链接：参考链接

4.用Python脚本生成一个Fat-tree型的拓扑，截图

!/usr/bin/python

"""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
L3 = L2
c = []
a = []
e = []

add core ovs

for i in range( L1 ):
sw = self.addSwitch( 'c{}'.format( i + 1 ) )
c.append( sw )

add aggregation ovs

for i in range( L2 ):
sw = self.addSwitch( 'a{}'.format( L1 + i + 1 ) )
a.append( sw )

add edge ovs

for i in range( L3 ):
sw = self.addSwitch( 'e{}'.format( L1 + L2 + i + 1 ) )
e.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 links between aggregation and edge ovs

for i in range( 0, L2, 2 ):
for sw1 in a[i:i+2]:
for sw2 in e[i:i+2]:
self.addLink( sw2, sw1 )

add hosts and its links with edge ovs

count = 1
for sw1 in e:
for i in range(2):
host = self.addHost( 'h{}'.format( count ) )
self.addLink( sw1, host )
count += 1
topos = { 'mytopo': ( lambda: MyTopo() ) }