SDN上机第2次作业
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
创建名为test.py的文件
代码
class Topotest( Topo ):
def __init__( self ):
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: Topotest() ) }
输入命令执行文件创建拓扑
sudo mn --custom test.py --topo mytopo --switch ovsk,protocols=OpenFlow13
然后pingall
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
sw1
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,in_port=2,actions=push_vlan:0x8100,set_field:4096->vlan_vid,output:1
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,in_port=3,actions=push_vlan:0x8100,set_field:4097->vlan_vid,output:1
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,in_port=4,actions=push_vlan:0x8100,set_field:4098->vlan_vid,output:1
//让主机1,2,3进入交换机1的包打上vlan_tag转发到端口1
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,dl_vlan=0,actions=pop_vlan,output:2
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,dl_vlan=1,actions=pop_vlan,output:3
sudo ovs-ofctl -O OpenFlow13 add-flow s1 priority=1,dl_vlan=2,actions=pop_vlan,output:4
//将从端口1得到的包去除vlan_tag并依据tag转发到端口2,3，4
sw2
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,in_port=2,actions=push_vlan:0x8100,set_field:4096->vlan_vid,output:1
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,in_port=3,actions=push_vlan:0x8100,set_field:4097->vlan_vid,output:1
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,in_port=4,actions=push_vlan:0x8100,set_field:4098->vlan_vid,output:1
//让主机4，5,6进入交换机2的包打上vlan_tag转发到端口1
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,dl_vlan=0,actions=pop_vlan,output:2
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,dl_vlan=1,actions=pop_vlan,output:3
sudo ovs-ofctl -O OpenFlow13 add-flow s2 priority=1,dl_vlan=2,actions=pop_vlan,output:4
//将从端口1得到的包去除vlan_tag并依据tag转发到端口2,3，4
3. 直接在Open vSwitch查看流表，提交OVS命令执行结果
输入以下命令查看流表
sudo ovs-ofctl -O OpenFlow13 dump-flows s1
sudo ovs-ofctl -O OpenFlow13 dump-flows s2
4. 提交主机连通性测试结果，验证流表的有效性
回到原终端pingall
5. 利用Wireshark抓包，分析验证特定报文
启动
sudo wireshark
