实验7：基于REST API的SDN北向应用实践
一、实验目的
1.能够编写程序调用OpenDaylight REST API实现特定网络功能；
2.能够编写程序调用Ryu REST API实现特定网络功能。
二、实验环境
1.下载虚拟机软件Oracle VisualBox或VMware；
2.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；
新建拓扑图，并且启动OpenDaylight
sudo mn --topo=single,3 --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13
启动OpenDaylight
./distribution-karaf-0.6.4-Carbon/bin/karafz
在浏览器访问http://127.0.0.1:8181/index.html
（2） 下发指令删除s1上的流表数据。
delete.py代码如下：
点击查看代码
#!/usr/bin/python
import requests
from requests.auth import HTTPBasicAuth
def http_delete(url):
url= url
headers = {'Content-Type':'application/json'}
resp = requests.delete(url, headers=headers, auth=HTTPBasicAuth('admin', 'admin'))
return resp
if __name__ == "__main__":
url = 'http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:1/'
resp = http_delete(url)
print(resp.content)
put.py代码如下：
点击查看代码
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("./flowtimeout.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)
flowtimeout.json代码如下：
点击查看代码
# timeout.json
{
"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"
}
]
}
get.py代码如下：
点击查看代码
#!/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)
关闭ODL控制器，关闭上次的拓扑并清除拓扑后
使用命令ryu-manager ryu.app.simple_switch_13 ryu.app.ofctl_rest打开Ryu控制器
h1 ping h3，同时运行ryu硬超时运行ryu_timeout，h1 ping h3中断20秒
（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。
ryu_topo.py：
点击查看代码
#ryu_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())}
使用命令ryu-manager ryu.app.simple_switch_13 ryu.app.ofctl_rest打开Ryu控制器
使用命令sudo mn --custom topo.py --topo mytopo --mac --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13
创建拓扑：
ryu_vlan.py：
点击查看代码
# 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)
删除流表：
运行结果：
四、个人总结
通过本次实验，进一步学习了OpenDaylight和ryu，进一步区分了两者的区别所在，同时在实验中遇到问题查看了相关文档，锻炼了阅读文档的能力。这次的实验对我来说非常有难度，大部分的地方需要进行编写python程序，
而且实验过程中需要调用OpenDaylight和ryu的北向接口来实现一些特定的网络功能。