SDN大作业 ODL-负载均衡-example-2

代码位置
Github

实验概述

使用两个互为备份的中心交换机
连接两两互为备份的共计四个交换机
下接四组各连有两台主机的交换机
作为数据中心类型网络拓扑的一个小型实现
上、中、下层均可以扩展来实现对更多网络主机的支持
实现在网络中心区域防止单个设备故障所引发的网络中断

实验拓扑

实验环境部署

建立流程如下
1.开ODL
./karaf
ODL需求组件（没有请顺序安装）

install odl-restconf
install odl-l2switch-switch-ui
install odl-openflowplugin-all
install odl-mdsal-apidocs
install odl-dlux-core
install odl-dlux-node
install odl-dlux-yangui

2.运行mininet建立拓扑结构
sudo mn --custom datacenter.py --topo mytopo --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13

mininet的拓扑结构的Python代码如下：

datacenter.py

#!/usr/bin/python
#创建网络拓扑
"""Custom topology example
Adding the 'topos' dict with a key/value pair to generate our newly defined
topology enables one to pass in '--topo=mytopo' from the command line.
"""
 
from mininet.topo import Topo
from mininet.net import Mininet
from mininet.node import RemoteController,CPULimitedHost
from mininet.link import TCLink
from mininet.util import dumpNodeConnections
 
class MyTopo( Topo ):
    "Simple topology example."
 
    def __init__( self ):
        "Create custom topo."
 
        # Initialize topology
        Topo.__init__( self )
        L1 = 2
        L2 = L1 * 2 
        L3 = L2
        c = []
        a = []
        e = []
          
        # add core ovs  
        for i in range( L1 ):
                sw = self.addSwitch( 'c{}'.format( i + 1 ) )
                c.append( sw )
    
        # add aggregation ovs
        for i in range( L2 ):
                sw = self.addSwitch( 'a{}'.format( L1 + i + 1 ) )
                a.append( sw )
    
        # add edge ovs
        for i in range( L3 ):
                sw = self.addSwitch( 'e{}'.format( L1 + L2 + i + 1 ) )
                e.append( sw )
 
        # add links between core and aggregation ovs
        for i in range( L1 ):
                sw1 = c[i]
                for sw2 in a[i/2::L1/2]:
                # self.addLink(sw2, sw1, bw=10, delay='5ms', loss=10, max_queue_size=1000, use_htb=True)
			            self.addLink( sw2, sw1 )
 
        # add links between aggregation and edge ovs
        for i in range( 0, L2, 2 ):
                for sw1 in a[i:i+2]:
	                for sw2 in e[i:i+2]:
			            self.addLink( sw2, sw1 )
 
        #add hosts and its links with edge ovs
        count = 1
        for sw1 in e:
                for i in range(2):
                	host = self.addHost( 'h{}'.format( count ) )
                	self.addLink( sw1, host )
                	count += 1
topos = { 'mytopo': ( lambda: MyTopo() ) }

3.打开http://127.0.0.1:8181/index.html#/topology来查看拓扑

也可查看节点相关信息

下发初始流表连接链路

备注：在此之前已经给本文件夹所有文件赋予权限
在下图路径中

sudo chmod -R 777 example-2
1.清空所有流表项
./delflows.sh

delflows.sh

sudo ovs-ofctl -O Openflow13 del-flows c1
sudo ovs-ofctl -O Openflow13 del-flows c2
sudo ovs-ofctl -O Openflow13 del-flows a3
sudo ovs-ofctl -O Openflow13 del-flows a4
sudo ovs-ofctl -O Openflow13 del-flows a5
sudo ovs-ofctl -O Openflow13 del-flows a6
sudo ovs-ofctl -O Openflow13 del-flows e7
sudo ovs-ofctl -O Openflow13 del-flows e8
sudo ovs-ofctl -O Openflow13 del-flows e9
sudo ovs-ofctl -O Openflow13 del-flows e10

2.下发流表（上中下层合在一起下发）
./add.sh

add.sh

#下层
#e7
sudo ovs-ofctl -O OpenFlow13 add-flow e7 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e7 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e7 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e7 priority=2,in_port=4,actions=output:1,output:2,output:3
#e8
sudo ovs-ofctl -O OpenFlow13 add-flow e8 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e8 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e8 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e8 priority=2,in_port=4,actions=output:1,output:2,output:3
#e9
sudo ovs-ofctl -O OpenFlow13 add-flow e9 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e9 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e9 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e9 priority=2,in_port=4,actions=output:1,output:2,output:3
#e10
sudo ovs-ofctl -O OpenFlow13 add-flow e10 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e10 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e10 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow e10 priority=2,in_port=4,actions=output:1,output:2,output:3

#中层
#a3
sudo ovs-ofctl -O OpenFlow13 add-flow a3 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a3 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a3 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a3 priority=2,in_port=4,actions=output:1,output:2,output:3
#a4
sudo ovs-ofctl -O OpenFlow13 add-flow a4 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a4 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a4 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a4 priority=2,in_port=4,actions=output:1,output:2,output:3
#a5
sudo ovs-ofctl -O OpenFlow13 add-flow a5 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a5 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a5 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a5 priority=2,in_port=4,actions=output:1,output:2,output:3
#a6
sudo ovs-ofctl -O OpenFlow13 add-flow a6 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a6 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a6 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a6 priority=2,in_port=4,actions=output:1,output:2,output:3

#底层
#c1
sudo ovs-ofctl -O OpenFlow13 add-flow c1 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow c1 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow c1 priority=2,in_port=3,actions=output:1,output:2
sudo ovs-ofctl -O OpenFlow13 add-flow c1 priority=2,in_port=4,actions=output:1,output:2
#c2
sudo ovs-ofctl -O OpenFlow13 add-flow c2 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow c2 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow c2 priority=2,in_port=3,actions=output:1,output:2
sudo ovs-ofctl -O OpenFlow13 add-flow c2 priority=2,in_port=4,actions=output:1,output:2

测试链路可用性

1.在mininet中运行pingall命令

说明链路已经连接成功
2.测试带宽
h1-h2

h1-h3

h1-h7

不难得出结论：随着跨交换机网络的转发，性能随着跨交换机网络而减弱
为了数据在跨多交换机传输时能获得更高的可用带宽，我们利用基于时间段给交换机分片（组）的方式来实现负载均衡（提高可用带宽）

负载均衡实现

通过将某段时间流表设置成c1,a3,a5一组和c2,a4,a6一组来达到交换机的负载均衡，以提高性能。
将分组代码整合在一起并运行
./auto.py

auto.py

import os
import time
def runteam1():
	os.system("./addt1.sh")
	time.sleep(1)
	os.system("./delt2.sh")
	return 1;
def runteam2():
	os.system("./addt2.sh")
	time.sleep(1)
	os.system("./delt1.sh")
	return 1;
os.system("./delflows.sh")
os.system("./inite.sh")
while(True):
	runteam1()
	runteam2()

其中addt1.sh和delt1.sh如下（addt2.sh和delt2.sh类似）

addt1.sh

#c1
sudo ovs-ofctl -O OpenFlow13 add-flow c1 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow c1 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow c1 priority=2,in_port=3,actions=output:1,output:2
sudo ovs-ofctl -O OpenFlow13 add-flow c1 priority=2,in_port=4,actions=output:1,output:2
#a3
sudo ovs-ofctl -O OpenFlow13 add-flow a3 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a3 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a3 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a3 priority=2,in_port=4,actions=output:1,output:2,output:3
#a5
sudo ovs-ofctl -O OpenFlow13 add-flow a5 priority=2,in_port=1,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a5 priority=2,in_port=2,actions=output:3,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a5 priority=2,in_port=3,actions=output:1,output:2,output:4
sudo ovs-ofctl -O OpenFlow13 add-flow a5 priority=2,in_port=4,actions=output:1,output:2,output:3

delt1.sh

sudo ovs-ofctl -O Openflow13 del-flows c1
sudo ovs-ofctl -O Openflow13 del-flows a3
sudo ovs-ofctl -O Openflow13 del-flows a5

负载均衡后再次执行链路性能测试(测试结果取同一时段的三次均值，因为网络会有波动）
h1-h2因为没有链路变化所以带宽基本不变
负载均衡前
负载均衡后
h1-h3带宽略有增加，但是变化不明显
负载均衡前
负载均衡后
h1-h7带宽提升很多，变换明显
负载均衡前
负载均衡后