       Installation Instructions for OpenFlow Reference Release

This document describes how to build, install, and execute the
reference implementation of OpenFlow.  Please send any comments to:

                      <openflow-discuss@openflowswitch.org>

Contents
========

The OpenFlow reference implementation includes one OpenFlow switch
implementations:

	- The "userspace datapath-based switch": This divides the switch
	  into a userspace "datapath" (built as udatapath/ofdatapath)
	  and a userspace program that implements the secure channel
	  component (ofprotocol).  The userspace datapath-based switch
	  does not require building a kernel module, but it is not as
	  fast as a kernel-based switch.

The reference implementation also contains a simple OpenFlow
controller (built as controller/controller) and a number of related
utilities.

Build Methods
=============

There are two principal ways to build and install this distribution:

	- Using "configure" and "make" in the ordinary way.  See
          Building Conventionally below for detailed instructions.

	- As a set of Debian packages.  Refer to Building Debian
          Packages, below, for instructions.

Base Prerequisites
------------------

Regardless of how it is built, OpenFlow has a common set of
prerequisites.  To compile the userspace programs in the OpenFlow
reference distribution, you will need the following software:

    - A make program, e.g. GNU make
      (http://www.gnu.org/software/make/).  BSD make should also work.

    - The GNU C compiler (http://gcc.gnu.org/).  We generally test
      with version 4.1 or 4.2.

    - libssl, from OpenSSL (http://www.openssl.org/), is optional but
      recommended.  libssl is required to establish confidentiality
      and authenticity in the connections among OpenFlow switches and
      controllers.  To enable, configure with --enable-ssl=yes.

If you are working from a Git tree or snapshot (instead of from a
distribution tarball), or if you modify the OpenFlow build system, you
will also need the following software:

    - Autoconf version 2.60 or later (http://www.gnu.org/software/autoconf).

    - Automake version 1.10 or later (http://www.gnu.org/software/automake).

    - pkg-config (http://pkg-config.freedesktop.org/wiki/).  We test
      with version 0.22.

Debian Prerequisites
--------------------

To build Debian packages from the OpenFlow distribution, you will need
to install a number of Debian packages in addition to the base
prerequisites listed above.  These additional prerequisites may be
found listed as "Build-Depends" in debian/control in the source tree.
To check that they are installed, first install the dpkg-dev package,
then run dpkg-checkbuilddeps from the top level of the OpenFlow source
tree.

To build Debian packages without being root, also install the
"fakeroot" package.

Userspace Switch Prerequisites
---------------------------------

     - To enable slicing support, "tc" frontend should be installed
       (from iproute2, part of all major distributions,
       http://www.linux-foundation.org/en/Net:Iproute2).
       You also need to enable the following kernel configuration
       options under the QoS and/or Fair queueing section :
       CONFIG_NET_SCHED,CONFIG_NET_SCH_HTB (already configured that
       way in most distributions).
       (NOTE: You can disable slicing (and these dependencies) at runtime
        using the --no-slicing option)

Building Conventionally
=======================

This section explains how to build and install the OpenFlow
distribution in the ordinary way using "configure" and "make".

0. Check that you have installed all the prerequisites listed above in
   the Base Prerequisites section.

1. In the top source directory, configure the package by running the
   configure script.  You can usually invoke configure without any
   arguments:

      % ./configure

   To use a specific C compiler for compiling OpenFlow user programs,
   also specify it on the configure command line, like so:

      % ./configure CC=gcc-4.2

   The configure script accepts a number of other options and honors
   additional environment variables.  For a full list, invoke
   configure with the --help option.

2. Run make in the top source directory:

      % make

   The following binaries will be built:

      - Userspace datapath: udatapath/ofdatapath.

      - Secure channel executable: secchan/ofprotocol.

      - Controller executable: controller/controller.

      - Datapath administration utility: utilities/dpctl.

      - Runtime logging configuration utility: utilities/vlogconf.

      - Miscellaneous utilities: utilities/ofp-discover,
        utilities/ofp-kill.

      - Tests: various binaries in tests/.

   If your distribution includes the OpenFlow extensions, the
   following additional binaries will be built:

      - ANSI terminal support for EZIO 16x2 LCD panel:
        ext/ezio/ezio-term.

      - Switch monitoring UI for small text displays:
        ext/ezio/ofp-switchui.

3. Run "make install" to install the executables and manpages into the
   running system, by default under /usr/local.

4. Test the userspace programs, as described under Testing Userspace
   Programs below.

Building Debian Packages
========================

Follow these instructions to build Debian packages for OpenFlow.

0. Check that you have installed all the prerequisites listed above in
   the Base Prerequisites and Debian Prerequisites sections above.

1. In the top source directory, run the following command, as root:

      % dpkg-buildpackage

   Alternatively, if you installed the "fakeroot" package, you may run
   dpkg-buildpackage as an ordinary user with the following syntax:

      % dpkg-buildpackage -rfakeroot

   The following packages will be built in the directory above the
   source tree:

      - openflow-controller: The OpenFlow controller.  Depends on
        openflow-pki (see below).

      - openflow-switch: Install this package on a machine that acts
        as an OpenFlow kernel switch.

      - openflow-datapath-source: Source code for OpenFlow's Linux
        kernel module.

      - openflow-pki: Public-key infrastructure for OpenFlow.  Install
        this package on a machine that acts as an OpenFlow PKI server
        (see "Establishing a Public Key Infrastructure" below).

      - openflow-common: Files and utilities required by more than one
        of the above packages.

2. To set up an OpenFlow controller, install the openflow-controller
   package and its dependencies.  You may configure it by editing
   /etc/default/openflow-controller, e.g. to enable non-SSL
   connections, which are disabled by default.  If you change the
   default settings, you will need to restart the controller by
   running:

      % /etc/init.d/openflow-controller restart

3. To set up an OpenFlow switch, install the openflow-switch package
   and its dependencies.  If it is to be a kernel-based switch, also
   install openflow-datapath-source, then follow the instructions in
   /usr/share/doc/openflow-datapath-source/README.Debian to build and
   install the kernel module.

   You may configure the switch one of the following ways:

      - Completely by hand, as described under the Testing section
        below.

        For the userspace datapath-based switch, this is the only
        supported form of configuration.

      - By editing /etc/default/openflow-switch.  You must at least
        configure some network devices, by uncommenting NETDEVS and
        adding the appropriate devices to the list, e.g. NETDEVS="eth0
        eth1".

        After you edit this file, you will need to start the switch by
        running:

           % /etc/init.d/openflow-switch restart

        This form of configuration is not supported for the userspace
        datapath-based switch.

      - By running the ofp-switch-setup program.  This interactive
        program will walk you through all the steps of configuring an
        OpenFlow switch, including configuration of SSL certificates.
        Run it without arguments, as root:

           % ofp-switch-setup

        This form of configuration is not supported for the userspace
        datapath-based switch.

Testing
=======

The following sets of instructions show how to use the OpenFlow
reference implementation as a switch on a single machine.  This can be
used to verify that the distribution built properly.  For full
installation instructions, refer to the Installation section below.

Userspace Datapath
------------------

These instructions use the OpenFlow userspace datapath ("ofdatapath").

1. Start the OpenFlow controller running in the background, by running
   the "controller" program with a command like the following:

      # controller punix:/var/run/controller.sock &

   This command causes the controller to bind to the specified Unix
   domain socket, awaiting connections from OpenFlow switches.  See
   controller(8) for details.

   The "controller" program does not require any special privilege, so
   you do not need to run it as root.
   
2. The commands below must run as root, so log in as root, or use a
   program such as "su" to become root temporarily.

3. Create a datapath instance running in the background.  The command
   below creates a datapath that listens for connections from ofprotocol
   on a Unix domain socket located in /var/run and services physical
   ports eth1 and eth2:

      # ofdatapath punix:/var/run/dp0.sock -i eth1,eth2 &

4. Run ofprotocol to start the secure channel connecting the datapath and
   the controller:

      # ofprotocol unix:/var/run/controller.sock unix:/var/run/dp0.sock &
   
5. Devices plugged into the network ports specified in step 2 should
   now be able to send packets to each other, as if they were plugged
   into ports on a conventional Ethernet switch.

Installation
============

This section explains how to install OpenFlow in a network with one
controller and one or more switches, each of which runs on a separate
machine.  Before you begin, you must decide on one of two ways for
each switch to reach the controller over the network:

      - Use a "control network" that is completely separate from the
        "data network" to be controlled ("out-of-band control").  The
        location of the controller must be configured manually in this
        case.

      - Use the same network for control and for data ("in-band
        control").  When in-band control is used, the location of the
        controller may be configured manually or discovered
        automatically.  We will assume manual configuration here;
        please refer to ofprotocol(8) for instructions on setting up
        controller discovery.  

Controller Setup
----------------

On the machine that is to be the OpenFlow controller, start the
"controller" program listening for connections from switches on TCP
port 6633 (the default), as shown below.

   # controller -v ptcp:

(See controller(8) for more details)

Make sure the machine hosting the controller is reachable by the
switch.

Userspace Datapath-Based Setup
------------------------------

On a machine that is to host an OpenFlow userspace datapath-based
switch, follow the procedure below.

0. The commands below must run as root, so log in as root, or use a
   program such as "su" to become root temporarily.

1. Create a datapath instance running in the background.  The command
   below creates a datapath that listens for connections from ofprotocol
   on a Unix domain socket located in /var/run, services physical
   ports eth1 and eth2, and creates a TAP network device named "tap0"
   for use in in-band control:

      # ofdatapath punix:/var/run/dp0.sock -i eth1,eth2 --local-port=tap:tap0 &

   (See ofdatapath(8) for details.)

   If the switch will connect to the controller out-of-band, then the
   --local-port option may be omitted, or --no-local-port may be
   substituted.

3. Arrange so that the switch can reach the controller over the
   network.

      - If you are using out-of-band control, at this point make sure
        that the switch machine can reach the controller over the
        network.

      - If you are using in-band control with manual configuration, at
        this point the TAP network device created in step 1 is not
        bridged to any physical network, so the next step depends on
        whether connectivity is required to configure the device's IP
        address:

           * If the switch has a static IP address, you may configure
             its IP address now, e.g.:

                # ifconfig tap0 192.168.1.1

           * If the switch does not have a static IP address, e.g. its
             IP address is obtained dynamically via DHCP, then proceed
             to step 4.  The DHCP client will not be able to contact
             the DHCP server until the secure channel has started up.

      - If you are using in-band control with controller discovery, no
        configuration is required at this point.  You may proceed to
        step 4.

4. Run ofprotocol to start the secure channel connecting the datapath to
   a remote controller.  If the controller is running on host
   192.168.1.2 port 6633 (the default port), the ofprotocol invocation
   would look like this:

      # ofprotocol unix:/var/run/dp0.sock tcp:192.168.1.2

   - If you are using in-band control with controller discovery, omit
     the second argument to the ofprotocol command.

   - If you are using out-of-band control, add --out-of-band to the
     command line.

5. If you are using in-band control with manual configuration, and the
   switch obtains its IP address dynamically, then you may now obtain
   the switch's IP address, e.g. by invoking a DHCP client.  The
   secure channel will only be able to connect to the controller after
   an IP address has been obtained.

6. The secure channel should connect to the controller within a few
   seconds.  It may take a little longer if controller discovery is in
   use, because the switch must then also obtain its own IP address
   and the controller's location via DHCP.

Configuration
=============

Secure operation over SSL
-------------------------

The instructions above set up OpenFlow for operation over a plaintext
TCP connection.  Production use of OpenFlow should use SSL[*] to
ensure confidentiality and authenticity of traffic among switches and
controllers.  The source must be configured with --enable-ssl=yes to
build with SSL support.

To use SSL with OpenFlow, you must set up a public-key infrastructure
(PKI) including a pair of certificate authorities (CAs), one for
controllers and one for switches.  If you have an established PKI,
OpenFlow can use it directly.  Otherwise, refer to "Establishing a
Public Key Infrastructure" below.

To configure the controller to listen for SSL connections on port 6633
(the default), invoke it as follows:

      # controller -v pssl: --private-key=PRIVKEY --certificate=CERT \
            --ca-cert=CACERT

where PRIVKEY is a file containing the controller's private key, CERT
is a file containing the controller CA's certificate for the
controller's public key, and CACERT is a file containing the root
certificate for the switch CA.  If, for example, your PKI was created
with the instructions below, then the invocation would look like:

      # controller -v pssl: --private-key=ctl-privkey.pem \
            --certificate=ctl-cert.pem --ca-cert=pki/switchca/cacert.pem

To configure a switch to connect to a controller running on port 6633
(the default) on host 192.168.1.2 over SSL, invoke ofprotocol as follows:

      # ofprotocol -v DATAPATH ssl:192.168.1.2 --private-key=PRIVKEY \
            --certificate=CERT --ca-cert=CACERT

where DATAPATH is the datapath to connect to (e.g. nl:0 or
unix:/var/run/dp0.sock), PRIVKEY is a file containing the switch's
private key, CERT is a file containing the switch CA's certificate for
the switch's public key, and CACERT is a file containing the root
certificate for the controller CA.  If, for example, your PKI was
created with the instructions below, then the invocation would look
like:

      # ofprotocol -v DATAPATH ssl:192.168.1.2 --private-key=sc-privkey.pem \
            --certificate=sc-cert.pem --ca-cert=pki/controllerca/cacert.pem

[*] To be specific, OpenFlow uses TLS version 1.0 or later (TLSv1), as
    specified by RFC 2246, which is very similar to SSL version 3.0.
    TLSv1 was released in January 1999, so all current software and
    hardware should implement it.

Establishing a Public Key Infrastructure
----------------------------------------

If you do not have a PKI, the ofp-pki script included with OpenFlow
can help.  To create an initial PKI structure, invoke it as:
      % ofp-pki init
which will create and populate a new PKI directory.  The default
location for the PKI directory depends on how the OpenFlow tree was
configured (to see the configured default, look for the --dir option
description in the output of "ofp-pki --help").

The pki directory contains two important subdirectories.  The
controllerca subdirectory contains controller certificate authority
related files, including the following:

    - cacert.pem: Root certificate for the controller certificate
      authority.  This file must be provided to ofprotocol with the
      --ca-cert option to enable it to authenticate valid controllers.

    - private/cakey.pem: Private signing key for the controller
      certificate authority.  This file must be kept secret.  There is
      no need for switches or controllers to have a copy of it.

The switchca subdirectory contains switch certificate authority
related files, analogous to those in the controllerca subdirectory:

    - cacert.pem: Root certificate for the switch certificate
      authority.  This file must be provided to the controller program
      with the --ca-cert option to enable it to authenticate valid
      switches.

    - private/cakey.pem: Private signing key for the switch
      certificate authority.  This file must be kept secret.  There is
      no need for switches or controllers to have a copy of it.

After you create the initial structure, you can create keys and
certificates for switches and controllers with ofp-pki.  To create a
controller private key and certificate in files named ctl-privkey.pem
and ctl-cert.pem, for example, you could run:
      % ofp-pki req+sign ctl controller
ctl-privkey.pem and ctl-cert.pem would need to be copied to the
controller for its use at runtime (they could then be deleted from
their original locations).  The --private-key and --certificate
options of controller, respectively, would point to these files.

Analogously, to create a switch private key and certificate in files
named sc-privkey.pem and sc-cert.pem, for example, you could run: 
      % ofp-pki req+sign sc switch
sc-privkey.pem and sc-cert.pem would need to be copied to the switch
for its use at runtime (they could then be deleted from their original
locations).  The --private-key and --certificate options,
respectively, of ofprotocol would point to these files.

Bug Reporting
-------------

Please report problems to:

openflow-discuss@openflowswitch.org

or post them to our online bug tracking system at:

http://www.openflowswitch.org/bugs/openflow
