SDN期末作业

一、项目描述

负载均衡程序

二、个人分工

小组成员：李文博，冉思银，侯振源，李熙，汪志彬

三、代码演示及过程描述

拓扑代码：

from mininet.topo import Topo

class MyTopo( Topo ):
"Simple topology example."

def init( self ):

# Initialize topology
Topo.__init__( self )
h1 = self.addHost('h1')
h2 = self.addHost('h2')
h3 = self.addHost('h3')
h4 = self.addHost('h4')

s1 = self.addSwitch('s1')
s2 = self.addSwitch('s2')
s3 = self.addSwitch('s3')
s4 = self.addSwitch('s4')

self.addLink(h1,s1)
self.addLink(s1,s2)
self.addLink(s1,s3)
self.addLink(s1,s4)
self.addLink(s2,s4)
self.addLink(s3,s4)
self.addLink(s4,h2)
self.addLink(s4,h3)
self.addLink(s4,h4)

topos = { 'mytopo': ( lambda: MyTopo() ) }

建成拓扑图

下发流表

import httplib2
import time

class OdlUtil:
url = ''
def init(self, host, port):
self.url = 'http://' + host + ':' + str(port)
def install_flow(self, container_name='default',username="admin", password="admin"):
http = httplib2.Http()
http.add_credentials(username, password)
headers = {'Accept': 'application/json'}
flow_name = 'flow_' + str(int(time.time()*1000))
s1zbody='{"group": [{ "group-type": "group-select","group-id": "1","group-name": "loadbalance","buckets": {"bucket": [{"bucket-id": "1","weight": "3","action": [{"order": "0","output-action": {"output-node-connector": "4"}}]},{"bucket-id": "2","weight": "2","action": [{"order": "0","output-action": {"output-node-connector": "2"}}]},{"bucket-id": "3","weight": "2","action": [{"order": "0","output-action": {"output-node-connector": "3"}}]}]}}]}'
s1lbody='{"flow": [{"id": "1","match": {"in-port": "1"},"instructions": {"instruction": [{"order": "0","apply-actions": {"action": [{"order": "0","group-action": {"group-id": "1"}}]}}]},"flow-name": "s1","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s2lbody='{"flow": [{"id": "1","match": {"in-port": "1"},"instructions": {"instruction": [{"order": "0","apply-actions": {"action": [{"order": "0","output-action": {"output-node-connector": "2"}}]}}]},"flow-name": "s2","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s3lbody='{"flow": [{"id": "1","match": {"in-port": "1"},"instructions": {"instruction": [{"order": "0","apply-actions": {"action": [{"order": "0","output-action": {"output-node-connector": "2"}}]}}]},"flow-name": "s3","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s4lbody='{"flow": [{"id": "1","match": {"in-port": "2","ethernet-match": {"ethernet-type": {"type": "0x0800"}},"ipv4-destination": "10.0.0.2/32"},"instructions": {"instruction": [{"order": "0","apply-actions":{"action": [{"order": "0","output-action": {"output-node-connector": "4"}}]}}]},"flow-name": "s4:s2toh2","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s4lbody2='{"flow": [{"id": "2","match": {"in-port": "2","ethernet-match": {"ethernet-type": {"type": "0x0800"}},"ipv4-destination": "10.0.0.3/32"},"instructions": {"instruction": [{"order": "0","apply-actions":{"action": [{"order": "0","output-action": {"output-node-connector": "5"}}]}}]},"flow-name": "s4:s2toh3","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s4lbody3='{"flow": [{"id": "3","match": {"in-port": "2","ethernet-match": {"ethernet-type": {"type": "0x0800"}},"ipv4-destination": "10.0.0.4/32"},"instructions": {"instruction": [{"order": "0","apply-actions":{"action": [{"order": "0","output-action": {"output-node-connector": "6"}}]}}]},"flow-name": "s4:s2toh4","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s4lbody4='{"flow": [{"id": "4","match": {"in-port": "1","ethernet-match": {"ethernet-type": {"type": "0x0800"}},"ipv4-destination": "10.0.0.2/32"},"instructions": {"instruction": [{"order": "0","apply-actions":{"action": [{"order": "0","output-action": {"output-node-connector": "4"}}]}}]},"flow-name": "s4:s1toh2","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s4lbody5='{"flow": [{"id": "5","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","output-action": {"output-node-connector": "5"}}]}}]},"flow-name": "s4:s1toh3","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s4lbody6='{"flow": [{"id": "6","match": {"in-port": "1","ethernet-match": {"ethernet-type": {"type": "0x0800"}},"ipv4-destination": "10.0.0.4/32"},"instructions": {"instruction": [{"order": "0","apply-actions":{"action": [{"order": "0","output-action": {"output-node-connector": "6"}}]}}]},"flow-name": "s4:s1toh4","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s4lbody7='{"flow": [{"id": "7","match": {"in-port": "3","ethernet-match": {"ethernet-type": {"type": "0x0800"}},"ipv4-destination": "10.0.0.2/32"},"instructions": {"instruction": [{"order": "0","apply-actions":{"action": [{"order": "0","output-action": {"output-node-connector": "4"}}]}}]},"flow-name": "s4:s3toh2","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s4lbody8='{"flow": [{"id": "8","match": {"in-port": "3","ethernet-match": {"ethernet-type": {"type": "0x0800"}},"ipv4-destination": "10.0.0.3/32"},"instructions": {"instruction": [{"order": "0","apply-actions":{"action": [{"order": "0","output-action": {"output-node-connector": "5"}}]}}]},"flow-name": "s4:s3toh3","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
s4lbody9='{"flow": [{"id": "9","match": {"in-port": "3","ethernet-match": {"ethernet-type": {"type": "0x0800"}},"ipv4-destination": "10.0.0.4/32"},"instructions": {"instruction": [{"order": "0","apply-actions":{"action": [{"order": "0","output-action": {"output-node-connector": "6"}}]}}]},"flow-name": "s4:s3toh4","priority": "1000","cookie": "0x0001","table_id": "0"}]}'
headers = {'Content-type': 'application/json'}
num=0
while num < 1 :
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:1/flow-node-inventory:group/1', body=s1zbody, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:1/flow-node-inventory:table/0/flow/1', body=s1lbody, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:2/flow-node-inventory:table/0/flow/1', body=s2lbody, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:3/flow-node-inventory:table/0/flow/1', body=s3lbody, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:4/flow-node-inventory:table/0/flow/1', body=s4lbody, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:4/flow-node-inventory:table/0/flow/2', body=s4lbody2, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:4/flow-node-inventory:table/0/flow/3', body=s4lbody3, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:4/flow-node-inventory:table/0/flow/4', body=s4lbody4, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:4/flow-node-inventory:table/0/flow/5', body=s4lbody5, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:4/flow-node-inventory:table/0/flow/6', body=s4lbody6, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:4/flow-node-inventory:table/0/flow/7', body=s4lbody7, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:4/flow-node-inventory:table/0/flow/8', body=s4lbody8, method='PUT',headers=headers)
response, content = http.request(uri='http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:4/flow-node-inventory:table/0/flow/9', body=s4lbody9, method='PUT',headers=headers)
num=num + 1
print(content.decode())
odl = OdlUtil('127.0.0.1', '8181')
odl.install_flow()

大概思路：

拓扑图左侧三台主机作为服务端，右侧为客户端，最初思路很简单是下发流表根据不同服务机送来的数据设置不同的优先级，使得一个服务机有一个专门的传输通路互不干扰达成负载均衡，但是后来发现这只是对应三台服务机一起工作的情况，如果只有一台服务机工作，明明有三条通路然而只使用一条通路进行传输没有实现负载均衡。重新思考后决定左侧三台的主机都先使用一条通路向客户端传输数据，然后检测传输通路使用情况如果发现三条通路负载不均衡再根据不同的流表将数据分路传输。但是实际做的时候碍于能力，如何检测通路使用情况的方法没有做好，还有下发的流表觉得不对，实验没有成功，截止日期将近没有办法写上没有完成的期末作业报告上交。

视频：
由于实验失败无视频

四、课程总结

SDN是一门新型的网络管理模式，通过上软件定义网络这门课使我对SDN有了初步的认识，虽然听上去用代码控制网络运行情况就觉得好像跟写实现一些小要求的代码一样容易，但是上机实验的时候才知道用软件代码实现网络控制并不容易，使用现有的SDN工具就觉得很不顺手，如果要深入学习还要多花时间和精力了解SDN，以及学习一些相关编程语言和计算机知识。当然自己的学习态度也是一个问题，当中期课程任务一多做一些环境准备有些麻烦就有些不怎么认真，作业也做得并不好。即使课程结束，为了了解更多计算机行业的新兴概念和知识，学习也不能懈怠，应继续努力学习。

附：SDN上机第二次作业和第三次作业博客内容已变动，补做了一些题目，请老师查收。

第二次上机作业：http://www.cnblogs.com/sheogorath/p/8360956.html

第三次上机作业：http://www.cnblogs.com/sheogorath/p/8053080.html