实验7:基于REST API的SDN北向应用实践
实验7:基于REST API的SDN北向应用实践
一、实验目的
能够编写程序调用OpenDaylight REST API实现特定网络功能;
能够编写程序调用Ryu REST API实现特定网络功能。
二、实验环境
下载虚拟机软件Oracle VisualBox或VMware;
在虚拟机中安装Ubuntu 20.04 Desktop amd64,并完整安装Mininet、OpenDaylight(Carbon版本)、Postman和Ryu;
三、实验要求
(一)基本要求
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;
(2) 下发指令删除s1上的流表数据。
(3) 下发硬超时流表,实现拓扑内主机h1和h3网络中断20s。
(4) 获取s1上活动的流表数。
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。
(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
创建拓扑图
sudo mn --custom topo.py --topo mytopo --mac --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13
topo.py
#!/usr/bin/env python
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())}
ryu_vlan.py
# ryu_vlan.py
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)
(二)进阶要求
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。
(三)实验小结
本次实验的主要内容是能够编写程序调用OpenDaylight REST API实现特定网络功能;能够编写程序调用Ryu REST API实现特定网络功能。
实验难度:比较困难
本次实验的实验内容是以先前几次实验为基础进行的,因此在进行实验时需要回顾之前所学习的内容与知识,因此实验的内容也比较多并且要编写程序,编写代码的难度比较大。并且新学习了SHELL脚本,以及如何运行shell脚本。