1.利用mininet创建如下拓扑,要求拓扑支持OpenFlow 1.3协议,主机名、交换机名以及端口对应正确,请给出拓扑Mininet执行结果,展示端口连接情况
1.1拓扑
![image.png](https://upload-images.jianshu.io/upload_images/19526787-acfcf72fe8dce6b2.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
1.2 代码
#!/usr/bin/python
from mininet.topo import Topo
class MyTopo( Topo ):
"Simple topology example."
def __init__( self ):
# Initialize topology
Topo.__init__( self )
sw1 = self.addSwitch('s1')
sw2 = self.addSwitch('s2')
h1 = self.addHost('h1')
h2 = self.addHost('h2')
h3 = self.addHost('h3')
h4 = self.addHost('h4')
h5 = self.addHost('h5')
h6 = self.addHost('h6')
self.addLink(h1,sw1,1,1)
self.addLink(h2,sw1,1,2)
self.addLink(h3,sw1,1,3)
self.addLink(sw1,sw2,4,4)
self.addLink(h4,sw2,1,1)
self.addLink(h5,sw2,1,2)
self.addLink(h6,sw2,1,3)
topos = { 'mytopo': ( lambda: MyTopo() ) }
1.3创建
![image.png](https://upload-images.jianshu.io/upload_images/19526787-445a7e80d0b00d0c.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
1.4使用net命令查看拓扑
![image.png](https://upload-images.jianshu.io/upload_images/19526787-2ec7bc5cb4bbc872.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
1.5使用pingall命令测试所有节点连通性
![image.png](https://upload-images.jianshu.io/upload_images/19526787-06488cfcce505018.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
2.直接在Open vSwitch下发流表,用vlan得到下列虚拟网段,请逐条说明所下发的流表含义
2.1流表
![image.png](https://upload-images.jianshu.io/upload_images/19526787-54df3746c50cd180.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
2.2含义
- 将主机1,2,3进入s1的包打上vlan tag,转发端口4
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,in_port=1,actions=push_vlan:0x8100,set_field:4096-\>vlan_vid,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,in_port=2,actions=push_vlan:0x8100,set_field:4097-\>vlan_vid,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,in_port=3,actions=push_vlan:0x8100,set_field:4098-\>vlan_vid,output:4
- 将从端口4的包去除vlan tag, 并根据tag进行转发
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,dl_vlan=0,actions=pop_vlan,output:1
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,dl_vlan=1,actions=pop_vlan,output:2
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,dl_vlan=2,actions=pop_vlan,output:3
- 将主机4,5,6进入s2的包打上vlan tag,转发端口4
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,in_port=1,actions=push_vlan:0x8100,set_field:4096-\>vlan_vid,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,in_port=2,actions=push_vlan:0x8100,set_field:4097-\>vlan_vid,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,in_port=3,actions=push_vlan:0x8100,set_field:4098-\>vlan_vid,output:4
- 将从端口4的包去除vlan tag, 并根据tag进行转发
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,dl_vlan=0,actions=pop_vlan,output:1
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,dl_vlan=1,actions=pop_vlan,output:2
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,dl_vlan=2,actions=pop_vlan,output:3
3. 直接在Open vSwitch查看流表,提交OVS命令执行结果
3.1命令
sudo ovs-ofctl dump-flows s1
sudo ovs-ofctl dump-flows s2
3.2结果
- s1
![image.png](https://upload-images.jianshu.io/upload_images/19526787-334b0c21251a41a2.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
- s2
![image.png](https://upload-images.jianshu.io/upload_images/19526787-19886118d082e338.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
4. 提交主机连通性测试结果,验证流表的有效性
![image.png](https://upload-images.jianshu.io/upload_images/19526787-a81d491d2c44eed5.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
5. 利用Wireshark抓包,分析验证特定报文
5.1命令
sudo wireshark
5.2截图
![image.png](https://upload-images.jianshu.io/upload_images/19526787-8b9efdbfff62fe31.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)