2019 SDN上机第6次作业

一、实验拓扑

• python脚本

from mininet.topo import Topo
 
class MyTopo( Topo ):
    "Simple topology example."
 
    def __init__( self ):
 
        # Initialize topology
        Topo.__init__( self )
        
        s1 = self.addSwitch('s1')
        s2 = 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,s1,1,1)
        self.addLink(h2,s1,1,2)
        self.addLink(h3,s1,1,3)
        self.addLink(s1,s2,4,4)
        self.addLink(h4,s2,1,1)
        self.addLink(h5,s2,1,2)
        self.addLink(h6,s2,1,3)

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

• 生成拓扑

sudo mn --custom a.py --topo mytopo --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13

• 测试连通性

• 连接ryu控制器

二、使用Ryu的REST API下发流表实现和第2次实验同样的VLAN

Ryu控制器的API文档：ryu.app.ofctl_rest

• 编写脚本12_5.sh

#端口号1发来数据
curl -X POST -d '{
    "dpid": 1,
    "priority":1,
    "match":{
        "in_port":1
    },
    "actions":[
        {
            "type": "PUSH_VLAN",     # s1将从主机发来的数据包打上vlan_tag
            "ethertype": 33024       # 帧类型0x8100(=33024): 表示IEEE 802.1Q的VLAN数据帧
        },
        {
            "type": "SET_FIELD",
            "field": "vlan_vid",     # 设置VLAN ID
            "value": 4096            # 设置vlan_id的值
        },
        {
            "type": "OUTPUT",
            "port": 4
        }
    ]
}' http://127.0.0.1:8080/stats/flowentry/add

#端口号2发来数据
curl -X POST -d '{
    "dpid": 1,
    "priority":1,
    "match":{
        "in_port":2
    },
    "actions":[
        {
            "type": "PUSH_VLAN",     # s1将从主机发来的数据包打上vlan_tag
            "ethertype": 33024       # 帧类型0x8100(=33024): 表示IEEE 802.1Q的VLAN数据帧
        },
        {
            "type": "SET_FIELD",
            "field": "vlan_vid",     # 设置VLAN ID
            "value": 4097            # 设置vlan_id的值
        },
        {
            "type": "OUTPUT",
            "port": 4
        }
    ]
}' http://127.0.0.1:8080/stats/flowentry/add

#端口号3发来数据
curl -X POST -d '{
    "dpid": 1,
    "priority":1,
    "match":{
        "in_port":3
    },
    "actions":[
        {
            "type": "PUSH_VLAN",     # s1将从主机发来的数据包打上vlan_tag
            "ethertype": 33024       # 帧类型0x8100(=33024): 表示IEEE 802.1Q的VLAN数据帧
        },
        {
            "type": "SET_FIELD",
            "field": "vlan_vid",     # 设置VLAN ID
            "value": 4098            # 设置vlan_id的值
        },
        {
            "type": "OUTPUT",
            "port": 4
        }
    ]
}' http://127.0.0.1:8080/stats/flowentry/add



#向端口1转发
curl -X POST -d '{
    "dpid": 1,
    "priority":1,
    "match":{
        "dl_vlan": "0"
    },
    "actions":[
        {
            "type": "POP_VLAN",     # 给进入交换机的包去除 vlan_tag
        },
        {
            "type": "OUTPUT",
            "port": 1
        }
    ]
}' http://localhost:8080/stats/flowentry/add

#向端口2转发
curl -X POST -d '{
    "dpid": 1,
    "priority":1,
    "match":{
        "dl_vlan": "1"
    },
    "actions":[
        {
            "type": "POP_VLAN",     # 给进入交换机的包去除 vlan_tag
        },
        {
            "type": "OUTPUT",
            "port": 2
        }
    ]
}' http://localhost:8080/stats/flowentry/add

#向端口3转发
curl -X POST -d '{
    "dpid": 1,
    "priority":1,
    "match":{
        "dl_vlan": "2"
    },
    "actions":[
        {
            "type": "POP_VLAN",     # 给进入交换机的包去除 vlan_tag
        },
        {
            "type": "OUTPUT",
            "port": 3
        }
    ]
}' http://localhost:8080/stats/flowentry/add

s2把改成2即可

• 执行sh 12_5.sh语句

• 查看流表

sudo ovs-ofctl -O OpenFlow13 dump-flows s1
sudo ovs-ofctl -O OpenFlow13 dump-flows s2

• 查看下发流表后的连通性

三、对比两种方法，写出你的实验体会

ryu查看流表更方便、更容易理解和使用。REST是一种针对网络应用的设计和开发方式，可以降低开发的复杂性，提高系统的可伸缩性。而且可以用shell编写脚本，一键执行下发流表，很方便。