P4 Tutorial
If you are reading this while not attending a live P4 tutorial class, see below for links to information about recently given live classes.
Introduction
Welcome to the P4 Tutorial! We've prepared a set of exercises to help you get started with P4 programming, organized into several modules:
- Introduction and Language Basics
- P4Runtime and the Control Plane
- Monitoring and Debugging
- Advanced Behavior
- Stateful Packet Processing
Presentation
The slides are available online and in the P4_tutorial.pdf in the tutorial directory.
A P4 Cheat Sheet is also available online which contains various examples that you can refer to.
P4 Documentation
The documentation for P4_16 and P4Runtime is available here
All excercises in this repository use the v1model architecture, the documentation for which is available at:
- The BMv2 Simple Switch target document accessible here talks mainly about the v1model architecture.
- The include file
v1model.p4
has extensive comments and can be accessed here.
Obtaining required software
If you are starting this tutorial at one of the proctored tutorial events, then we've already provided you with a virtual machine that has all of the required software installed. Ask an instructor for a USB stick with the VM image.
Otherwise, to complete the exercises, you will need to either build a virtual machine or install several dependencies.
To build the virtual machine
- Install Vagrant and VirtualBox
- Clone the repository
- Before proceeding, ensure that your system has at least 12 Gbytes of free disk space, otherwise the installation can fail in unpredictable ways.
cd vm-ubuntu-20.04
vagrant up
- The time for this step to complete depends upon your computer and Internet access speeds, but for example with a 2015 MacBook pro and 50 Mbps download speed, it took a little less than 20 minutes. It requires a reliable Internet connection throughout the entire process.- When the machine reboots, you should have a graphical desktop machine with the required software pre-installed. There are two user accounts on the VM,
vagrant
(passwordvagrant
) andp4
(passwordp4
). The accountp4
is the one you are expected to use.
Note: Before running the vagrant up
command, make sure you have enabled virtualization in your environment; otherwise you may get a "VT-x is disabled in the BIOS for both all CPU modes" error. Check this for enabling it in virtualbox and/or BIOS for different system configurations.
You will need the script to execute to completion before you can see the p4
login on your virtual machine's GUI. In some cases, the vagrant up
command brings up only the default vagrant
login with the password vagrant
. Dependencies may or may not have been installed for you to proceed with running P4 programs. Please refer the existing issues to help fix your problem or create a new one if your specific problem isn't addressed there.
To install P4 development tools on an existing system
There are instructions and scripts in another Github repository that can, starting from a freshly installed Ubuntu 20.04 or 22.04 Linux system with enough RAM and free disk space, install all of the necessary P4 development tools to run the exercises in this repository. You can find those instructions and scripts here (note that you must clone a copy of that entire repository in order for its install scripts to work).
Older tutorials
Multiple live tutorial classes have been given using the example code in this repository for hands-on exercises. For example, there is one each April or May at the P4 workshop at Stanford University in California, and there have been several at networking conferences such as ACM SIGCOMM.
Please create an issue for this tutorials repository if you know a public link for classroom video recordings and/or pre-built VM images that currently do not have such a link.
ACM SIGCOMM August 2019 Tutorial on Programming the Network Data Plane
https://p4.org/events/2019-08-23-p4-tutorial/
The page linked above has a link to download a pre-built VM image used for this class, as well as instructions to build one yourself from a particular branch of this repository.
P4 Developer Day, April 2019
https://p4.org/events/2019-04-30-p4-developer-day/
Both a beginner and advanced class were taught at this event. The page linked above contains instructions to download and install a pre-built Linux VM that was used during the classes.
P4 Developer Day, November 2017
- YouTube
videos
- This link plays the first welcome video of a series of 6 videos of tutorials given at this event.