2019 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

（1）创建SDNtest2.py文档

from mininet.topo import Topo
 
class MyTopo( Topo ):
 
    def __init__( self ):
 
        # Initialize topology
        Topo.__init__( self )
        
        switch1 = self.addSwitch('switch1')
        switch2 = self.addSwitch('switch2')

        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,switch1,1,1)
        self.addLink(h2,switch1,1,2)
        self.addLink(h3,switch1,1,3)
        self.addLink(switch1,switch2,4,4)
        self.addLink(h4,switch2,1,1)
        self.addLink(h5,switch2,1,2)
        self.addLink(h6,switch2,1,3)

topos = { 'mytopo': ( lambda: MyTopo() ) }

（2）输入如下命令，创建拓扑

sudo mn --custom ./SDNtest2.py --topo mytopo --controller=remote,ip=127.0.0.1,port=6653 --switch ovsk,protocols=OpenFlow13

（3）使用pingall命令测试所有节点连通性

2. 直接在Open vSwitch下发流表，实现如下连通性要求，请逐条说明所下发的流表含义

自己的虚拟机上没安装OVS，又重新安装了老师的镜像在上面做实验(╥﹏╥)

• h1 -- h4互通
• h2 -- h5互通
• h3 -- h6互通

• 其余主机不通
  

• 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

4. 提交主机连通性测试结果，验证流表的有效性

5. 利用Wireshark抓包，分析验证特定报文