实验7:基于REST API的SDN北向应用实践

1.编写Python程序,调用OpenDaylight的北向接口实现以下功能

(1) 利用Mininet平台搭建下图所示网络拓扑,并连接OpenDaylight;
a.打开odl控制器

./distribution-karaf-0.6.4-Carbon/bin/karaf

b.创建拓扑

sudo mn --topo=single,3 --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13

(2) 下发指令删除s1上的流表数据。
a.delete.py代码

#!/usr/bin/python
import requests
from requests.auth import HTTPBasicAuth
if __name__ == "__main__":
    url = 'http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:1/'
    headers = {'Content-Type': 'application/json'}
    res = requests.delete(url, headers=headers, auth=HTTPBasicAuth('admin', 'admin'))
    print (res.content)

(3) 下发硬超时流表,实现拓扑内主机h1和h3网络中断20s。

timeout.py文件

#!/usr/bin/python
import requests
from requests.auth import HTTPBasicAuth
if __name__ == "__main__":
    url = 'http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:1/'
    headers = {'Content-Type': 'application/json'}
    res = requests.delete(url, headers=headers, auth=HTTPBasicAuth('admin', 'admin'))
    print (res.content)

timeout.json文件

{
  "flow": [
    {
      "id": "1",
      "match": {
        "in-port": "1",
        "ethernet-match": {
          "ethernet-type": {
            "type": "0x0800"
          }
        },
        "ipv4-destination": "10.0.0.3/32"
      },
      "instructions": {
        "instruction": [
          {
            "order": "0",
            "apply-actions": {
              "action": [
                {
                  "order": "0",
                  "drop-action": {}
                }
              ]
            }
          }
        ]
      },
      "flow-name": "flow",
      "priority": "65535",
      "hard-timeout": "20",
      "cookie": "2",
      "table_id": "0"
    }
  ]
}

(4) 获取s1上活动的流表数

getflow.py

#!/usr/bin/python
import requests
from requests.auth import HTTPBasicAuth
if __name__ == "__main__":
    url = 'http://127.0.0.1:8181/restconf/operational/opendaylight-inventory:nodes/node/openflow:1/flow-node-inventory:table/0/opendaylight-flow-table-statistics:flow-table-statistics'
    headers = {'Content-Type': 'application/json'}
    res = requests.get(url,headers=headers, auth=HTTPBasicAuth('admin', 'admin'))
    print (res.content)

编写Python程序,调用Ryu的北向接口实现以下功能

(1) 实现上述OpenDaylight实验拓扑上相同的硬超时流表下发。

ryu控制器

ryu-manager ryu.app.simple_switch_13 ryu.app.ofctl_rest

ryu_timeout.py

import requests
from requests.auth import HTTPBasicAuth

if __name__ == '__main__':
    url = 'http://127.0.0.1:8080/stats/flowentry/add'
    headers = {'Content-Type': 'application/json'}
    json = open('ryu_timeout.json').read()
    response = requests.post(url, data=json, headers=headers)
    print(response.content)


ryu_timeout.json

{
    "dpid": 1,
    "cookie": 1,
    "cookie_mask": 1,
    "table_id": 0,
    "hard_timeout": 20,
    "priority": 65535,
    "flags": 1,
    "match":{
        "in_port":1
    },
    "actions":[]
 }

(2) 参考Ryu REST API的文档,基于VLAN实验的网络拓扑,编程实现相同的VLAN配置。
提示:拓扑生成后需连接Ryu,且Ryu应能够提供REST API服务

ryu_topo.py代码

from mininet.topo import Topo
 
class ryu_topo(Topo):
    def __init__(self):
        Topo.__init__(self)

        self.addSwitch("s1")
        self.addSwitch("s2")
 
        self.addHost("h1")
        self.addHost("h2")
        self.addHost("h3")
        self.addHost("h4")
 
        self.addLink("s1", "h1")
        self.addLink("s1", "h2")
        self.addLink("s2", "h3")
        self.addLink("s2", "h4")
        self.addLink("s1", "s2")
 
topos = {'ryu_topo': (lambda: ryu_topo())}

ryu_vlan.py代码

import json
import requests

if __name__ == '__main__':
    url = 'http://127.0.0.1:8080/stats/flowentry/add'
    headers = {'Content-Type': 'application/json'}
    f = open('ryu_vlan.json').read()
    flows = json.loads(f)['flows']
    [requests.post(url, data=json.dumps(flows[i]), headers=headers) for i in range(0, 8)]

ryu_vlan.json代码

{
	"flows": [
        {
			"dpid": 1,
			"priority": 1,
			"match": {
				"in_port": 1
			},
			"actions": [{
					"type": "PUSH_VLAN",
					"ethertype": 33024
				},
				{
					"type": "SET_FIELD",
					"field": "vlan_vid",
					"value": 4096
				},
				{
					"type": "OUTPUT",
					"port": 3
				}
			]
		},
		{
			"dpid": 1,
			"priority": 1,
			"match": {
				"in_port": 2
			},
			"actions": [{
					"type": "PUSH_VLAN",
					"ethertype": 33024
				},
				{
					"type": "SET_FIELD",
					"field": "vlan_vid",
					"value": 4097
				},
				{
					"type": "OUTPUT",
					"port": 3
				}
			]
		},
		{
			"dpid": 1,
			"priority": 1,
			"match": {
				"vlan_vid": 0
			},
			"actions": [{
					"type": "POP_VLAN",
					"ethertype": 33024
				},
				{
					"type": "OUTPUT",
					"port": 1
				}
			]
		},
		{
			"dpid": 1,
			"priority": 1,
			"match": {
				"vlan_vid": 1
			},
			"actions": [{
					"type": "POP_VLAN",
					"ethertype": 33024
				},
				{
					"type": "OUTPUT",
					"port": 2
				}
			]
		},
		{
			"dpid": 2,
			"priority": 1,
			"match": {
				"in_port": 1
			},
			"actions": [{
					"type": "PUSH_VLAN",
					"ethertype": 33024
				},
				{
					"type": "SET_FIELD",
					"field": "vlan_vid",
					"value": 4096
				},
				{
					"type": "OUTPUT",
					"port": 3
				}
			]
		}, 
        {
			"dpid": 2,
			"priority": 1,
			"match": {
				"in_port": 2
			},
			"actions": [{
					"type": "PUSH_VLAN",
					"ethertype": 33024
				},
				{
					"type": "SET_FIELD",
					"field": "vlan_vid",
					"value": 4097
				},
				{
					"type": "OUTPUT",
					"port": 3
				}
			]
		},
		{
			"dpid": 2,
			"priority": 1,
			"match": {
				"vlan_vid": 0
			},
			"actions": [{
					"type": "POP_VLAN",
					"ethertype": 33024
				},
				{
					"type": "OUTPUT",
					"port": 1
				}
			]
		},
		{
			"dpid": 2,
			"priority": 1,
			"match": {
				"vlan_vid": 1
			},
			"actions": [{
					"type": "POP_VLAN",
					"ethertype": 33024
				},
				{
					"type": "OUTPUT",
					"port": 2
				}
			]
		}
	]
}

创建一个拓扑并清空流表

sudo mn --custom ryu_topo.py --topo ryu_topo --mac --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13
curl -X DELETE http://127.0.0.1:8080/stats/flowentry/clear/1
curl -X DELETE http://127.0.0.1:8080/stats/flowentry/clear/2
ryu-manager ryu.app.simple_switch_13 ryu.app.ofctl_rest  //打开RYU

个人总结

这次的PPT给的提示比较少,主要是编写代码的部分难,因此参考了其他同学的代码,其他的操作在实验四和实验五都做过了. 忘记了也可以看看之前的资料.

posted on 2022-11-02 21:54  zzzxxzxzxzxzxz  阅读(145)  评论(0编辑  收藏  举报

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