2019 SDN上机第6次作业

1.实验拓扑

(1)拓扑图如下：

(2)python脚本如下:

from mininet.topo import Topo
class MyTopo(Topo):

    def __init__(self):

        # initilaize topology
        Topo.__init__(self)

        # add hosts and switches
        h1 = self.addHost('h1')
        h2 = self.addHost('h2')
        h3 = self.addHost('h3')
        h4 = self.addHost('h4')
        h5 = self.addHost('h5')
        h6 = self.addHost('h6')
        s1 = self.addSwitch('s1')
        s2 = self.addSwitch('s2')

        # add links
        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())}

(3)使用以下命令生成拓扑:

sudo mn --custom sdn6.py --topo mytopo --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13

(4)输入net查看各主机与交换机之间的端口情况，使用pingall测试连通性

(5)输入以下命令连接ryu控制器

ryu-manager ofctl_rest.py

2.使用Ryu的REST API下发流表实现和第2次实验同样的VLAN

(1)编写shell脚本（a.sh）如下：

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

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

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


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

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

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



curl -X POST -d '{
    "dpid": 2,
    "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


curl -X POST -d '{
    "dpid": 2,
    "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


curl -X POST -d '{
    "dpid": 2,
    "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

curl -X POST -d '{
    "dpid": 2,
    "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

curl -X POST -d '{
    "dpid": 2,
    "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

curl -X POST -d '{
    "dpid": 2,
    "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

(2)执行a.sh，发现ryu控制器已接受流表项，结果如下:

(3)查看s1 s2流表

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

(4)pingall查看连通性

3.对比两种方法，写出你的实验体会

两个方法思想相同，但ryu更容易理解和使用，查看和修改更方便。实验二中是使用ovs命令直接在交换机上下发流表实现VLAN，而本次实验则是通过Ryu控制器来实现，并且相关的实验内容内容可以保存在文件中随时修改查看，同时修改时也只要修改几个参数，不会像实验二那样关闭命令行就消失重新做。因此通过ryu控制器操作起来方便多了。