Tutorial

These instructions demonstrate how to use OpenNF to quickly and safely move an active TCP flow from one network function (NF) to another. These instructions were developed using Ubuntu 14.04.1 (LTS) 64-bit, but they should work on any Linux distribution with a few modifications.

1. Install dependencies

• Install dependencies for the controller, shared library for NFs, and tutorial:
  sudo apt-get install git tcpreplay mininet ant oracle-java8-installer gcc make wget
  You will need to add the WebUpd8 repository to install Oracle Java using apt. If you prefer, you can install Mininet from source.
• A controller (openvswitch-controller) that interferes with the OpenNF controller is automatically installed and started when Mininet is installed. Stop this service:
  sudo service openvswitch-controller stop
• Stop the network-manager service if it is running on your system:
  sudo service network-manager stop
  Any active network managers will interfere with Mininet.
• Manually install json-c. You may need to install other dependencies via apt.
• Install dependencies for the network function used in the tutorial, PRADS:
  sudo apt-get install libpcre3-dev libpcap-dev python-docutils

2. Download code for the SDN controller and network functions

• Create a directory called tutorial:
  mkdir tutorial
• Download and untar the code for Floodlight 0.90 in the tutorial directory:
  cd tutorial
  wget http://floodlight-download.projectfloodlight.org/files/floodlight-source-0.90.tar.gz
  tar xzvf floodlight-source-0.90.tar.gz
• Clone the code for PRADS into the tutorial directory:
  git clone https://github.com/gamelinux/prads.git
  cd prads
  git checkout 930ff5

3. Download the OpenNF code

Please fill out our request form to obtain access to the code.

• Download and untar the NF controller code in the tutorial directory.
• Download and untar the shared library for NFs code in the tutorial directory.
• Download and untar the applications code in the tutorial directory.
• Download the PRADS patch in the tutorial directory.
• Download and untar the Mininet topology script in the tutorial directory.

4. Compile the network function

• Compile the shared library for NFs:
  cd tutorial/shared/
  make
  make install
  If desired, you can set the PREFIX environment variable to install the shared library in a location other than /usr/local.
• Patch and compile PRADS:
  cd tutorial/prads/
  patch -p1 < ../prads.patch
  make
  sudo make install
  If desired, you can set the PREFIX environment variable to install PRADS in a location other than /usr/local. If you installed the shared library for NFs in a non-standard location, then set the LDFLAGS environment variable to contain the -L argument with the path to the directory containing the shared library for NFs.

5. Compile the controller

• To tell Floodlight about the existence of the OpenNF controller and application modules, you need to modify Floodlight's module list file net.floodlightcontroller.core.module.IFloodlightModule in the directory tutorial/floodlight/src/main/resources/META-INF/services/. You should add the following lines:
  edu.wisc.cs.wisdom.sdmbn.core.SdmbnManager
  edu.wisc.cs.wisdom.sdmbn.apps.testing.TestTimedMoveAll
• Compile Floodlight:
  cd tutorial/floodlight/
  ant
• Symlink the Floodlight JAR file into the libraries for the controller:
  cd tutorial/controller/lib/
  ln -s ../../floodlight-0.90/target/floodlight.jar
• Download the GSON Jar file into tutorial/controller/lib/.
• Compile the controller:
  cd tutorial/controller/
  ant
• Compile the applications:
  cd tutorial/apps/
  ant

6. Configure the demo

• Update some of the configuration lines in the controller configuration at tutorial/apps/testTimedMoveAll.prop to the appropriate values:
  net.floodlightcontroller.core.FloodlightProvider.openflowport = 6633
  edu.wisc.cs.wisdom.sdmbn.core.SdmbnManager.stateport = 7790
  edu.wisc.cs.wisdom.sdmbn.core.SdmbnManager.eventport = 7791
  edu.wisc.cs.wisdom.sdmbn.apps.testing.TestTimedMoveAll.TraceReplaySwitchPort = 1
  edu.wisc.cs.wisdom.sdmbn.apps.testing.TestTimedMoveAll.TraceReplayHost = 192.168.0.1
  edu.wisc.cs.wisdom.sdmbn.apps.testing.TestTimedMoveAll.TraceReplayFile = youtube.pcap
  
• We need to generate a large packet capture file which we can replay. An easy way to do this is to start watching a video in YouTube. Run the following commands:
  cd tutorial/apps
  tcpdump -i <your active interface, i.e. eth0> -c 25000 -w youtube.pcap tcp
  It is important that the packet capture only contains IPv4 TCP packets (no IPv6, UDP, or ICMP).
• Update some of the configuration lines in the shared library for NFs configuration file at /usr/local/etc/sdmbn.conf to the appropriate values:
  ctrl_ip = 192.168.0.254
  If you installed the shared library for NFs in a different location, then use that path to the configuration file instead.

7. Run the demo

• In one terminal window, start the controller application:
  cd tutorial/apps/
  java -jar SDMBNapps.jar -cf testTimedMoveAll.prop
• In another terminal window, start the Mininet network:
  cd tutorial/
  sudo python tutorial_topo.py
• Once you start the Mininet network, you should notice some activity in the controller window as the OpenFlow switch connects to the controller. Wait for the switch to connect before proceeding.
• From the mininet window, open an xterm window for three hosts:
  mininet> xterm h1 h2 h3
• In the h1 xterm window, start the traceload server:
  cd tutorial/apps/
  bash scripts/traceload_server.sh h1-eth0 . 192.168.0.1 8080
• In the h2 xterm window, start PRADS:
  prads -i h2-eth0
• In the h3 xterm window, start PRADS:
  prads -i h3-eth0
• At this point, assuming everything is running correctly, you will see the following sequence of events:
  • The controller window acknowledges the PRADS connections from h2 and h3
  • The controller sends a command to start the trace replay on h1
  • On h1, the traceload server starts replaying packets, and the PRADS instance on h2 has a burst of activity as packets start coming in
  • A few seconds later, the controller initiates a move
  • The activity on h2 stops and then picks up again on h3
  • When the packet file finishes replaying, the pkts_received values in h2 and h3 should add up roughly to the total number of packets indicated in h1
• At the end of the demo, your screen should look something like this: