SDN
SDN Introduction
SDN literally software-defined network, the entire network will become SDN (NE just) open in the vertical direction, standardization, programmable, so that it is easier, more efficient use of network resources.
In traditional architecture, switches and routers have to operate in the implementation of the entire intelligence network under the control of 6000 kinds of distributed protocols. This means that even if there is only one network element adds a new agreement, all other network elements also need to make appropriate structural changes. In fact, add a new protocol on the network often take years to finalize the standardization process to actual deployment.
Mininet
What is Mininet
Mininet by some virtual terminal node (end-hosts), switches, routers connected together in a network simulator, which uses lightweight virtualization technology allows the system can be comparable to the real network.
Mininet can easily create a support network of SDN: host computer work like a real, like, you can use ssh to log, start the application program can send data packets to the Ethernet port, the packet will be a switch, a router receives and processes . With this network, the flexibility to add new features for the network and associated tests, and then easily deploy it to real hardware environments.
Mininet Installation and Deployment
Mininet virtual machine installation
- Download Mininet Mirror: https://github.com/mininet/mininet/releases
- Download virtual machine software. VirtualBox , VMware Workstation
- Installation image
Local installation (recommended)
By pulling the source Git
git clone git://github.com/mininet/mininet
Installation Mininet, according to mininet / util / install.sh -h command select View
mininet/util/install.sh -n3V 2.5.0
After installation is complete, use the command Mininet test installation was successful
sudo mn --test pingall
Mininet installation package (the most convenient)
Mininet installation package in Ubuntu
sudo apt install mininet/precise-backports
Problems encountered during installation
Tip 6653 port is occupied
sudo service openvswitch-testcontroller stop
Internal interactive command
Create a default topology after use sudo mn enters the interactive
help #查看帮助命令
net #查看链路信息
nodes #查看网络里面有多少节点以及有什么节点
links #查看链路健壮性，看看某条链路是不是在正常工作
pingall #测试所有主机间通信
pingpair #只验证前两个主机连通性-
dump #节点信息
intfs #网络接口信息
iperf h1 h2 #测试H1 H2的带宽
link s1 s2 up#禁用或开始节点间的链路
iperfudp bw h1 h2 #测试H1 H2 的UDP带宽
xterm h1 #节点开启可视化操作
py net.addSwtich("s1") #执行python 表达式
py experiments
Add a h3 and connected to s1
py net.addHost('h3') #添加一个主机h3
py net.addLink(s1,net.get('h3')) #将s1 和 h3连接起来
py s1.attach('s1-eth3') #添加接口s1-eth3
py net.get('h3').cmd('ifconfig h3-eth0 10.3') #给h3设置ip
py dump #查看设备的信息
#发现我们的h3并没有显示我们设置的IP 依然为none
#我们需要h1 ping h3命令，让设备发现他的ip。在dump即可查看正确的设备信息。
OpenDaylight
1. Installation ODL dependencies
sudo apt-get update
sudo apt-get install openjdk-8-jdk
2. Download OpenDaylight Controller: http://www.opendaylight.org/software/downloads
tar zxvf distribution-karaf-0.3.0-Lithium.tar.gz
3. Configure Java environment
Open vi / etc / profile
Add the following code
JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-amd64
JRE_HOME=$JAVA_HOME/jre
CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH
source file
source /etc/profile
4. Test whether the installation is successful
cd distribution-karaf-0.3.0-Lithium
Execution ./bin/karaf
After the successful implementation
Flow table
The picture shows the current topology
Experimental objectives are:
h1 can not ping h2
dpctl del-flows
#清除所有流表,也可以使用sh ovs-ofctl s1 del-flows 针对S1删除流表
dpctl add-flow in_port=1,actions=output:2
#让1端口添加output 2端口
dpctl add-flow in_port=2,actions=output:3,output:1
#让2端口添加output 3,1端口
dpctl add-flow in_port=3,actions=output:2
#让3端口添加output 2端口
Enter pingall results
1 -> h2 X
h2 -> h1 h3
h3 -> X h2
One more experiment
Mission objectives is to make h1 and h2 through, h3 and h4 pass, h1 and h3 unreasonable.
According to the mission objectives, which is the only host in the same switch can communicate.
h1 s2 is connected to the port 2
h2 is connected to the third port s2
s3 h3 connected to port 2
h4 s3 connection port 3
As long as the switch can not communicate with each other. 1,3 switch port. Delete all flow table, the exchange added 2, 3.
dpctl del-flows
dpctl add-flow in_port=2,actions=output:3
dpctl add-flow in_port=3,actions=output:2
pingall results:
h1 -> h2 X X
h2 -> h1 X X
h3 -> X X h4
h4 -> X X h3
With another idea
S1 from the router to discard the entire port 1 can be achieved.
sh ovs-ofctl add-flow s1 priority=50,in_port=1,action=drop