期末作业验收

负载均衡程序

• 拓扑设计

• 部分control代码展示

		while(True):
			#获取s4端口1的流量
			uri = 'http://127.0.0.1:8181/restconf/operational/opendaylight-inventory:nodes/node/openflow:4/node-connector/openflow:4:1'
			response, content = http.request(uri=uri, method='GET')
			content = json.loads(content)
			statistics = content['node-connector'][0]['opendaylight-port-statistics:flow-capable-node-connector-statistics']
			bytes1 = statistics['bytes']['transmitted']
			#1秒后再次获取
			time.sleep(1)
			response, content = http.request(uri=uri, method='GET')
			content = json.loads(content)
			statistics = content['node-connector'][0]['opendaylight-port-statistics:flow-capable-node-connector-statistics']
			bytes2 = statistics['bytes']['transmitted']
			#在检测到s4的1口流量空闲时发的流表
			speed=float(bytes2-bytes1)/1
			if speed !=0 :#获取有效的速度
				if speed < 1000 :
					print 'speed =',speed,',  s2端口1空闲，数据包往1口通过'
				#下发默认的流表			
					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/41', 
                                        body=h2_to_s4_1, 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/51', 
                                        body=h3_to_s4_1, 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/61',
                                        body=h4_to_s4_1, method='PUT',headers=headers)
				#在检测到s2的1口流量满载时下发新的流表
				else :
					print 'speed =',speed,',  s2端口1满载，数据包改为往2口和3口通过'
				#h2数据包的流表
					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/41', 
                                        body=lh2_to_s4_1, 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/42', 
                                        body=h2_to_s4_2, 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/43', 
                                        body=h2_to_s4_3, method='PUT',headers=headers)
				#h3数据包的流表
					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/52', 
                                        body=h3_to_s4_2, 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/53', 
                                        body=h3_to_s4_3, method='PUT',headers=headers)
				#h4数据包的流表
					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/62', 
                                        body=h4_to_s4_2, 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/63', 
                                        body=h4_to_s4_3, method='PUT',headers=headers)

• scene代码

    from mininet.topo import Topo
    class MyTopo( Topo ):

        def __init__( self ):

            # initilaize topology   
            Topo.__init__( self )

            # add hosts and switches
            host1 = self.addHost( 'h1' )
            host2 = self.addHost( 'h2' )
        host3 = self.addHost( 'h3' )
	    host4 = self.addHost( 'h4' )
            switch1 = self.addSwitch( 's1' )
            switch2 = self.addSwitch( 's2' )
            switch3 = self.addSwitch( 's3' )
            switch4 = self.addSwitch( 's4' )
   	   	

            # add links
            self.addLink(host1,switch1)
            self.addLink(switch1,switch2)
            self.addLink(switch1,switch3)
            self.addLink(switch1,switch4)

            self.addLink(switch2,switch4)
            self.addLink(switch3,switch4)
    
            self.addLink(switch4,host2)
            self.addLink(switch4,host3)
            self.addLink(switch4,host4)

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

演示视频

https://github.com/laizhiping/final-exam-sdn#实验场景

程序分工

• 赖志平：控制流表下发，负载均衡策略实现，实验的统筹与指导实现

• 陈敏辉：测试与纰漏修改，ReadMe说明

• 陈甘霖：流表设计和修正和视频录制

• 陈家进：拓扑搭建、视频剪辑

学期总结

    1.了解了什么是 SDN ，openflow，SDN 的基本思想、特点。
    2.掌握了在mninet上创建拓扑并通过floodlight验证器正确
    3.运用ODL控制器下发流表并通过OVS命令查看验证;运用Postman通过ODL的北向接口下发流表
    4.运用Wireshark抓包验证拓扑结构的正确性
    5.对ECMP与负载均衡的定义及实现有一些了解，可以实现较简单的负载均衡场景
    6.课程新颖，走在时代前沿，一个学期的学习肯定是不够的，只是皮毛，在接下来的日子会继续了解相关方面的知识，以及考虑如何应用