實(shí)驗(yàn)7：基于REST API的SDN北向應(yīng)用實(shí)踐
Posted on 2022-10-25 21:43 寄風(fēng) 閱讀(51) 評(píng)論(0) 收藏 舉報(bào)實(shí)驗(yàn)7：基于REST API的SDN北向應(yīng)用實(shí)踐
二、實(shí)驗(yàn)環(huán)境
Ubuntu 20.04 Desktop amd64
三、實(shí)驗(yàn)要求
（一）基本要求
1.編寫(xiě)Python程序，調(diào)用OpenDaylight的北向接口實(shí)現(xiàn)以下功能
（1）利用Mininet平臺(tái)搭建下圖所示網(wǎng)絡(luò)拓?fù)洌⑦B接OpenDaylight；
拓?fù)浣Y(jié)構(gòu)
啟動(dòng)連接ODL控制器，查看圖形界面
（2) 下發(fā)指令刪除s1上的流表數(shù)據(jù)
delete.py
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）下發(fā)硬超時(shí)流表，實(shí)現(xiàn)拓?fù)鋬?nèi)主機(jī)h1和h3網(wǎng)絡(luò)中斷20s
timeout.py
#!/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.conten)
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"
}
]
}
實(shí)驗(yàn)截圖
（4） 獲取s1上活動(dòng)的流表數(shù)
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)
實(shí)驗(yàn)截圖
2.編寫(xiě)Python程序，調(diào)用Ryu的北向接口實(shí)現(xiàn)以下功能
（1） 實(shí)現(xiàn)上述OpenDaylight實(shí)驗(yàn)拓?fù)渖舷嗤挠渤瑫r(shí)流表下發(fā)
ryu_timeout.py
#!/usr/bin/python
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)
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":[
]
}
實(shí)驗(yàn)截圖
（2） 參考Ryu REST API的文檔，基于VLAN實(shí)驗(yàn)的網(wǎng)絡(luò)拓?fù)洌幊虒?shí)現(xiàn)相同的VLAN配置。
topo.py
#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())}
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)
實(shí)驗(yàn)截圖
進(jìn)階要求
查看前序VLAN實(shí)驗(yàn)拓?fù)渲兴泄?jié)點(diǎn)（含交換機(jī)、主機(jī)）的名稱(chēng)，以及顯示每臺(tái)交換機(jī)的所有流表項(xiàng)。
getnode.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()
實(shí)驗(yàn)截圖：
四、個(gè)人總結(jié)
本次實(shí)驗(yàn)是一個(gè)比較綜合的實(shí)驗(yàn)，包括的前幾次的實(shí)驗(yàn)內(nèi)容。最開(kāi)始ping不通，因?yàn)闆](méi)有連接OpenDaylight。調(diào)用Ryu的北向接口實(shí)現(xiàn)硬超時(shí)流表下發(fā)時(shí)，需要同時(shí)開(kāi)啟REST API和運(yùn)行一個(gè)支持OpenFlow 1.3的交換機(jī)：ryu-manager ryu/ryu/app/ofctl_rest.py ryu/ryu/app/simple_switch_13.py。無(wú)法識(shí)別“curl”，按照提示安裝sudo apt-get install curl。學(xué)會(huì)了調(diào)用OpenDaylight REST API實(shí)現(xiàn)特定網(wǎng)絡(luò)功能和調(diào)用Ryu REST API實(shí)現(xiàn)特定網(wǎng)絡(luò)功能。
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