bydoon

  博客园  :: 首页  :: 新随笔  :: 联系 :: 订阅 订阅  :: 管理

一、基本要求

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;

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

  • Beryllium 版本 连接OpenDaylight
    ./distribution-karaf-0.4.4-Beryllium-SR4/bin/karaf feature:install odl-restconf odl-l2switch-switch-ui odl-openflowplugin-all odl-mdsal-apidocs odl-dlux-core odl-dlux-node odl-dlux-yangui

(2) 下发指令删除s1上的流表数据。

  • 创建并编写delete.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)
  • 命令行输入 python3 delete.py

(3) 下发硬超时流表,实现拓扑内主机h1和h3网络中断20s。

  • 创建并编写 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/flow-node-inventory:table/0/flow/1'
    with open("./timeout.json") as file:
        str = file.read()
    headers = {'Content-Type': 'application/json'}
    res = requests.put(url, str, headers=headers, auth=HTTPBasicAuth('admin', 'admin'))
    print (res.content)
  • 创建并编写 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。

  • 创建并编写 getflow.py 文件
#!/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)

2.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。

  • 创建并编写 ryu_timeout.py 文件
# ryu_timeout.py
import requests
if __name__ == "__main__":
    url = 'http://127.0.0.1:8080/stats/flowentry/add'
    with open("./ryu_timeout.json") as file:
        str = file.read()
    headers = {'Content-Type': 'application/json'}
    res = requests.post(url, str, headers=headers)
    print (res.content)
  • 创建并编写 ryu_timeout.json 文件
# 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":[

    ]
 }
  • 关闭ODL控制器,关闭上次的拓扑并清除拓扑sudo mn -c
  • 启动ryu控制器 ryu-manager ryu.app.simple_switch_13 ryu.app.ofctl_rest
  • 创建拓扑 sudo mn --topo=single,3 --mac --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13
  • h1 ping h3 , 运行python3 ryu_timeout.py

(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。

  • 创建并编写 ryu_topo.py 文件
#topo.py
from mininet.topo import Topo

class MyTopo(Topo):
    def __init__(self):
        # initilaize topology
        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 = {'mytopo': (lambda: MyTopo())}
  • 创建并编写 ryu_vlan.py 文件
import json

import requests

if __name__ == "__main__":
    url = 'http://127.0.0.1:8080/stats/flowentry/add'
    headers = {'Content-Type': 'application/json'}
    flow1 = {
        "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
            }
        ]
    }
    flow2 = {
        "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
            }
        ]
    }
    flow3 = {
        "dpid": 1,
        "priority": 1,
        "match":{
            "vlan_vid": 0
        },
        "actions":[
            {
                "type": "POP_VLAN",    
                "ethertype": 33024     
            },
            {
                "type": "OUTPUT",
                "port": 1
            }
        ]
    }
    flow4 = {
        "dpid": 1,
        "priority": 1,
        "match": {
            "vlan_vid": 1
        },
        "actions": [
            {
                "type": "POP_VLAN", 
                "ethertype": 33024  
            },
            {
                "type": "OUTPUT",
                "port": 2
            }
        ]
    }
    flow5 = {
        "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
            }
        ]
    }
    flow6 = {
        "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
            }
        ]
    }
    flow7 = {
        "dpid": 2,
        "priority": 1,
        "match": {
            "vlan_vid": 0
        },
        "actions": [
            {
                "type": "POP_VLAN", 
                "ethertype": 33024  
            },
            {
                "type": "OUTPUT",
                "port": 1
            }
        ]
    }
    flow8 = {
        "dpid": 2,
        "priority": 1,
        "match": {
            "vlan_vid": 1
        },
        "actions": [
            {
                "type": "POP_VLAN", 
                "ethertype": 33024  
            },
            {
                "type": "OUTPUT",
                "port": 2
            }
        ]
    }
    res1 = requests.post(url, json.dumps(flow1), headers=headers)
    res2 = requests.post(url, json.dumps(flow2), headers=headers)
    res3 = requests.post(url, json.dumps(flow3), headers=headers)
    res4 = requests.post(url, json.dumps(flow4), headers=headers)
    res5 = requests.post(url, json.dumps(flow5), headers=headers)
    res6 = requests.post(url, json.dumps(flow6), headers=headers)
    res7 = requests.post(url, json.dumps(flow7), headers=headers)
    res8 = requests.post(url, json.dumps(flow8), headers=headers)
  • 关闭控制器,关闭上一次实验的拓扑并清除sudo mn -c

  • 启动Ryu控制器ryu-manager ryu.app.simple_switch_13 ryu.app.ofctl_rest

  • 创建拓扑sudo sudo mn --custom ryu_topo.py --topo mytopo --mac --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13

  • 安装curl sudo apt install curl

  • 删除流表
    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

  • 运行 python3 ryu_vlan.py

进阶要求

1.OpenDaylight或Ryu任选其一,编程实现查看前序VLAN实验拓扑中所有节点(含交换机、主机)的名称,以及显示每台交换机的所有流表项。

  • 创建并编写 getall.py 文件
 #getall.py
import requests
import time
import re

class GetNodes:
    def __init__(self, ip):
        self.ip = ip
        
    def get_switch_id(self):
        url = 'http://' + self.ip + '/stats/switches'
        re_switch_id = requests.get(url=url).json()
        switch_id_hex = []
        for i in re_switch_id:
            switch_id_hex.append(hex(i))

        return switch_id_hex

    def getflow(self):
        url = 'http://' + self.ip + '/stats/flow/%d'
        switch_list = self.get_switch_id()
        ret_flow = []
        for switch in switch_list:
            new_url = format(url % int(switch, 16))
            re_switch_flow = requests.get(url=new_url).json()
            ret_flow.append(re_switch_flow)
        return ret_flow

    def show(self):
        flow_list = self.getflow()
        for flow in flow_list:
            for dpid in flow.keys():
                dp_id = dpid
                switchnum= '{1}'.format(hex(int(dp_id)), int(dp_id))        
                print('s'+switchnum,end = " ")
                switchnum = int(switchnum)
            for list_table in flow.values():
                for table in list_table:          
                    string1 = str(table)
                    if re.search("'dl_vlan': '(.*?)'", string1) is not None:
                       num = re.search("'dl_vlan': '(.*?)'", string1).group(1);
                       if num == '0' and switchnum == 1:
                          print('h1',end = " ")
                       if num == '1' and switchnum == 1:
                          print('h2',end = " ")
                       if num == '0' and switchnum == 2:
                          print('h3',end = " ")
                       if num == '1' and switchnum == 2:
                          print('h4',end = " ")
        print("")
        flow_list = self.getflow()
        for flow in flow_list:
            for dpid in flow.keys():
                dp_id = dpid
                print('switch_name:s{1}'.format(hex(int(dp_id)), int(dp_id)))
            for list_table in flow.values():
                for table in list_table:
                    print(table)
s1 = GetNodes("127.0.0.1:8080")
s1.show()
  • 运行python3 getall.py


个人总结

  • 这次实验较为综合,用到了之前OpenDaylight和Ryu的相关知识,经过复习才顺利完成。经过这次实验,我大致了编写程序调用OpenDaylight REST API和Ryu REST API实现特定网络功能。虽然实验过程中小问题频发,好在参考资料还是比较丰富的,通过阅读相关文档和同学的帮助,参考相关例程最终顺利完成了实验。
    遇到的问题主要分两种。一是在删除流表的时候没有安装curl库报错,再安装完后Ryu又没有运行导致无法删除。二是遇到的问题是忘记用sudo mn -c清空拓扑,导致实验结果不对。
posted on 2022-11-09 22:47  镇海bydoon  阅读(43)  评论(0编辑  收藏  举报