<info@openflowswitch.org>
-Prerequisites
--------------
+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
+------------------
-To compile the userspace programs in the OpenFlow reference
-distribution, you will need the following software:
+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.
- 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.
+ 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
- pkg-config (http://pkg-config.freedesktop.org/wiki/). We test
with version 0.22.
-The optional Linux module has additional prerequisites, described
-later in the section "Building and Testing the Linux Kernel-Based
-Switch".
+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.
+
+Kernel-Based Switch Prerequisites
+---------------------------------
+
+The OpenFlow distribution also includes a Linux kernel module that can
+be used to achieve higher switching performance. To compile the
+kernel module, you must install the following in addition to the
+software listed in the "Base Prerequisites" section above:
-Building Userspace Programs
----------------------------
+ - A supported Linux kernel version. Please refer to README for a
+ list of supported versions.
-These instructions describe how to build the userspace components of
-the OpenFlow distribution. Refer to "Building and Testing the Linux
-Kernel-Based Switch", below, for additional instructions on how to
-build the optional Linux kernel module.
+ The OpenFlow datapath requires bridging support (CONFIG_BRIDGE)
+ to be built as a kernel module. (This is common in kernels
+ provided by Linux distributions.) The bridge module must not be
+ loaded or in use. If the bridge module is running (check with
+ "lsmod | grep bridge"), you must remove it ("rmmod bridge")
+ before starting the datapath.
+
+ In kernels prior to 2.6.9, VLAN support (CONFIG_VLAN_8021Q) must
+ be compiled either directly or as a module. Failure to do this
+ will cause an error on module insertion due to the
+ "dev_change_flags" symbol being undefined.
+
+ - The correct version of GCC for the kernel that you are building
+ the module against:
+
+ * To build a kernel module for a Linux 2.6 kernel, you need
+ the same version of GCC that was used to build that kernel
+ (usually version 4.0 or later).
+
+ * To build a kernel module for a Linux 2.4 kernel, you need an
+ earlier version of GCC, typically GCC 2.95, 3.3, or 3.4.
+
+ - A kernel build directory corresponding to the Linux kernel image
+ the module is to run on. Under Debian and Ubuntu, for example,
+ each linux-image package containing a kernel binary has a
+ corresponding linux-headers package with the required build
+ infrastructure.
+
+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. If you want to compile the Linux
+ kernel module, also check that the prequisites listed under
+ Kernel-Based Switch Prequisites are installed.
1. In the top source directory, configure the package by running the
configure script. You can usually invoke configure without any
% ./configure CC=gcc-4.2
+ To build the Linux kernel module, so that you can run the
+ kernel-based switch, add --with-l26 or --with-l24 option, or both,
+ to the configure script's command line. Refer to Building the
+ Linux Kernel-Based Switch, below, for more information.
+
The configure script accepts a number of other options and honors
additional environment variables. For a full list, invoke
configure with the --help option.
- Runtime logging configuration utility: utilities/vlogconf.
-3. (Optional) Run "make install" to install the executables and
- manpages into the running system, by default under /usr/local.
+ If you passed --with-l26 to configure, "make" will also build the
+ following kernel modules:
+
+ - datapath/linux-2.6/openflow_mod.ko
+
+ - datapath/linux-2.6/hwtable_<table>_mod.ko for each <table>
+ specified on --enable-hw-tables (if any).
+
+ If you passed --with-l24 to configure, "make" will also build the
+ following kernel modules:
+
+ - datapath/linux-2.4/openflow_mod.o
+
+ - datapath/linux-2.6/hwtable_<table>_mod.o for each <table>
+ specified on --enable-hw-tables (if any).
+
+3. Run "make install" to install the executables and manpages into the
+ running system, by default under /usr/local.
+
+4. If you built kernel modules, you may load them with "insmod", e.g.:
+
+ (Linux 2.6)
+ % insmod datapath/linux-2.6/openflow_mod.ko
+
+ (Linux 2.4)
+ % insmod datapath/linux-2.4/compat24_mod.o
+ % insmod datapath/linux-2.4/openflow_mod.o
+
+ After you load the openflow module, you may load one hardware switch
+ table module (if any were built) to enable support for that hardware
+ switching table.
+
+ The insmod program must be run as root. You may need to specify a
+ full path to insmod, e.g. /sbin/insmod. To verify that the modules
+ have been loaded, run "/sbin/lsmod" and check that openflow_mod is
+ listed.
+
+4. Test the userspace programs, as described under Testing Userspace
+ Programs below.
+
+5. If you built the kernel module, test the kernel-based switch, as
+ described under Testing the Kernel-Based Implementation below.
+
+Building the Linux Kernel-Based Switch
+--------------------------------------
+
+To build the kernel module, follow the build process described above,
+but pass the location of the kernel build directory as an additional
+argument to the configure script, as described under step 1 in that
+section. Specify the location on --with-l26 for Linux 2.6, --with-l24
+for Linux 2.4. For example, to build for a running instance of Linux
+2.6:
+
+ % ./configure --with-l26=/lib/modules/`uname -r`/build
+
+To build for a running instance of Linux 2.4:
+
+ % ./configure --with-l24=/lib/modules/`uname -r`/build
+
+If you wish to build OpenFlow for an architecture other than the
+architecture used for compilation, you may specify the kernel
+architecture string using the KARCH variable when invoking the
+configure script. For example, to build OpenFlow for MIPS with Linux
+2.4:
+
+ % ./configure --with-l24=/path/to/linux-2.4 KARCH=mips
+
+If you have hardware that supports accelerated OpenFlow switching, and
+you have obtained a hardware table module for your hardware and
+extracted it into the OpenFlow reference distribution source tree,
+then you may also enable building support for the hardware switching
+table with --enable-hw-tables. For example, if your hardware
+switching table is in a directory named datapath/hwtable-foomatic, you
+could compile support for it with the running Linux 2.6 kernel like
+so:
+
+ % ./configure --with-l26=/lib/modules/`uname -r`/build \
+ --enable-hw-tables=foomatic
+
+For more information about hardware table modules, please read
+README.hwtables at the root of the OpenFlow distribution tree.
+
+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 userspace or 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 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
+ 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
+ switch.
+
+Testing
+=======
Testing Userspace Programs
--------------------------
+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. Start the OpenFlow controller running in the background, by running
the "controller" program with a command like the following:
- % controller ptcp: &
+ # controller ptcp: &
This command causes the controller to bind to port 975 (the
default) awaiting connections from OpenFlow switches. See
switch, specifying network devices to use as switch ports on the -i
option as a comma-separated list, like so:
- % switch tcp:127.0.0.1 -i eth1,eth2
+ # switch tcp:127.0.0.1 -i eth1,eth2
The network devices that you specify should not have configured IP
- addresses. The switch program must run as root.
+ addresses.
3. The controller causes each switch that connects to it to act like a
learning Ethernet switch. Thus, devices plugged into the specified
for testing, but a more conventional setup would run a controller on
one machine and one or more switches on different machines. To do so,
simply specify the IP address of the controller as the first argument
-to the switch program (in place of 127.0.0.1). (Note: The current
-version of the switch and controller requires that they be connected
-through a "control network" that is physically separate from the one
-that they are controlling. Future releases will support in-band
-control communication.)
+to the switch program (in place of 127.0.0.1). (Note: The userspace
+switch must be connected to the controller over a "control network"
+that is physically separate from the one that the switch and
+controller are controlling. The kernel-based switch does not have
+this limitation.)
+
+Testing the Kernel-Based Implementation
+---------------------------------------
+
+The OpenFlow kernel module must be loaded, as described in the
+previous section, before it may be tested.
+
+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. The command below creates a datapath with
+ ID 0 (see dpctl(8) for more detailed usage information).
+
+ # dpctl adddp 0
+
+ In principle, openflow_mod supports multiple datapaths within the
+ same host, but this is rarely useful in practice.
+
+ If you built a support module for hardware accelerated OpenFlow
+ switching and you want to use it, you must load it before creating
+ the datapath with "dpctl adddp".
+
+2. Use dpctl to attach the datapath to physical interfaces on the
+ machine. Say, for example, you want to create a trivial 2-port
+ switch using interfaces eth1 and eth2, you would issue the following
+ commands:
+
+ # dpctl addif 0 eth1
+ # dpctl addif 0 eth2
+
+ You can verify that the interfaces were successfully added by asking
+ dpctl to print the current status of datapath 0:
+
+ # dpctl show 0
+
+3. (Optional) You can manually add flows to the datapath to test using
+ dpctl add-flows and view them using dpctl dump-flows. See dpctl(8)
+ for more details.
+
+4. The simplest way to test the datapath is to run the provided sample
+ controller on the host machine to manage the datapath directly using
+ netlink:
+
+ # controller -v nl:0
+
+ Once the controller is running, the datapath should operate like a
+ learning Ethernet switch. You may monitor the flows in the datapath
+ flow table using "dpctl dump-flows" command.
+
+The preceding instructions assume that the controller and the switch
+are running on the same machine. This is an easy configuration for
+testing, but a more conventional setup would run a controller on one
+machine and one or more switches on different machines. Use the
+following instructions to set up remote switches:
+
+1. Start the datapath and attach it to two or more physical ports as
+ described in the previous section.
+
+2. Run the controller in passive TCP mode on the host which will act as
+ the controller. In the example below, the controller will bind to
+ port 975 (the default) awaiting connections from secure channels.
+
+ # controller -v ptcp:
+
+ (See controller(8) for more details)
+
+ Make sure the machine hosting the controller is reachable by the switch.
+
+3. Arrange so that the switch can reach the controller over the
+ network. There are two ways to do this:
+
+ - Use a "control network" that is completely separate from the
+ "data network" to be controlled ("out-of-band control"). To
+ do so, configure a network device (one that has not been added
+ to the datapath with "dpctl addif") to access the control
+ network in the usual way.
+
+ - Use the same network for control and for data ("in-band
+ control"). For this purpose, each datapath nl:K has a
+ corresponding virtual network device named ofK.
+
+ When in-band control is used, the location of the controller
+ may be configured manually or discovered automatically:
+
+ * Manual configuration: Start by bringing up of0 before
+ you start the secure channel:
+
+ # ifconfig of0 up
+
+ Before the secure channel starts up, the of0 device
+ cannot send or receive any packets, 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 of0 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.
+
+ * Controller discovery: No special setup is required at
+ the switch, but you must specially configure a DHCP
+ server to give out the switch's IP address and to tell
+ it the location of the controller. See secchan(8) for
+ details.
+
+4. Run secchan on the datapath host to start the secure channel
+ connecting the datapath to a remote controller. (See secchan(8)
+ for usage details). The details depend on how you configured the
+ network in step 3:
+
+ - If you are using in-band control and controller discovery,
+ invoke secchan something like this:
+
+ # secchan -v nl:0
+
+ The secure channel should connect to the controller after it
+ obtains its own IP address and the controller's location via
+ DHCP. This can take a few seconds. Switch setup is now
+ complete.
+
+ - Otherwise, the secure channel should be configured to connect
+ to the controller's IP address on the port configured in step
+ 2. If the controller is running on host 192.168.1.2 port 975
+ (the default port) and the datapath ID is 0, the secchan
+ invocation would look like:
+
+ # secchan -v nl:0 tcp:192.168.1.2
+
+ If you are using out-of-band control, or if you are using
+ in-band control and the switch has a static IP address, the
+ secure channel should quickly connect to the controller.
+ Setup is now complete. Otherwise, proceed to step 5.
+
+5. If you are using the same network for control and data, 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.
+
+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.
+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
OpenFlow can use it directly. Otherwise, refer to "Establishing a
Public Key Infrastructure" below.
-To configure the controller to listen for SSL connections on the
-default port, invoke it as follows:
+To configure the controller to listen for SSL connections on port 976
+(the default), invoke it as follows:
- % controller -v pssl: --private-key=PRIVKEY --certificate=CERT \
+ # controller -v pssl: --private-key=PRIVKEY --certificate=CERT \
--ca-cert=CACERT
where PRIVKEY is a file containing the controller's private key, CERT
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 \
+ # 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 the
-default port on host 192.168.1.2 over SSL, invoke it as follows:
+To configure a switch to connect to a controller running on port 976
+(the default) on host 192.168.1.2 over SSL, invoke it as follows:
- % switch -v ssl:192.168.1.2 -i INTERFACES --private-key=PRIVKEY \
+ # switch -v ssl:192.168.1.2 -i INTERFACES --private-key=PRIVKEY \
--certificate=CERT --ca-cert=CACERT
-where INTERFACES is the command-separated list of network devices
+where INTERFACES is the command-separated list of network device
interfaces, 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:
- % secchan -v -i INTERFACES ssl:192.168.1.2 --private-key=sc-privkey.pem \
+ # secchan -v -i INTERFACES 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
locations). The --private-key and --certificate options,
respectively, of switch and secchan would point to these files.
-Building and Testing the Linux Kernel-Based Switch
---------------------------------------------------
-
-The OpenFlow distribution also includes a Linux kernel module that can
-be used to achieve higher switching performance at a cost in
-portability and ease of installation. Compiling the kernel module has
-the following prerequisites in addition to those listed in the
-"Prerequisites" section above:
-
- - A supported Linux kernel version. Please refer to README for a
- list of supported versions.
-
- The OpenFlow datapath requires bridging support (CONFIG_BRIDGE)
- to be built as a kernel module. (This is common in kernels
- provided by Linux distributions.) The bridge module must not be
- loaded or in use. If the bridge module is running (check with
- "lsmod | grep bridge"), you must remove it ("rmmod bridge")
- before starting the datapath.
-
- - The correct version of GCC for the kernel that you are building
- the module against:
-
- * To build a kernel module for a Linux 2.6 kernel, you need
- the same version of GCC that was used to build that kernel
- (usually version 4.0 or later).
-
- * To build a kernel module for a Linux 2.4 kernel, you need an
- earlier version of GCC, typically GCC 2.95, 3.3, or 3.4.
-
- - A kernel build directory corresponding to the Linux kernel image
- the module is to run on. Under Debian and Ubuntu, for example,
- each linux-image package containing a kernel binary has a
- corresponding linux-headers package with the required build
- infrastructure.
-
-To build the kernel module, follow the build process described under
-"Building Userspace Programs" above, but pass the location of the
-kernel build directory as an additional argument to the configure
-script, as described under step 1 in that section. Specify the
-location on --with-l26 for Linux 2.6, --with-l24 for Linux 2.4. For
-example, to build for a running instance of Linux 2.6:
-
- % ./configure --with-l26=/lib/modules/`uname -r`/build
-
-To build for a running instance of Linux 2.4:
-
- % ./configure --with-l24=/lib/modules/`uname -r`/build
-
-In addition to the binaries listed under step 2 in "Building Userspace
-Programs" above, "make" will build the following kernel modules:
-
- datapath/linux-2.6/openflow_mod.ko (if --with-l26 was specified)
- datapath/linux-2.4/openflow_mod.o (if --with-l24 was specified)
-
-Once you have built the kernel modules, activating them requires only
-running "insmod", e.g.:
-
- (Linux 2.6)
- % insmod datapath/linux-2.6/openflow_mod.ko
-
- (Linux 2.4)
- % insmod datapath/linux-2.4/compat24_mod.o
- % insmod datapath/linux-2.4/openflow_mod.o
-
-The insmod program must be run as root. You may need to specify a
-full path to insmod, which is usually in the /sbin directory. To
-verify that the modules have been loaded, run "lsmod" (also in /sbin)
-and check that openflow_mod appears in the result.
-
-Testing the Kernel-Based Implementation
----------------------------------------
-
-The OpenFlow kernel module must be loaded, as described in the
-previous section, before it may be tested.
-
-1. Create a datapath instance. The command below creates a datapath with
- ID 0 (see dpctl(8) for more detailed usage information).
-
- % dpctl adddp 0
-
- (In principle, openflow_mod supports multiple datapaths within the
- same host, but this is rarely useful in practice.)
-
-2. Use dpctl to attach the datapath to physical interfaces on the
- machine. Say, for example, you want to create a trivial 2-port
- switch using interfaces eth1 and eth2, you would issue the following
- commands:
-
- % dpctl addif 0 eth1
- % dpctl addif 0 eth2
-
- You can verify that the interfaces were successfully added by asking
- dpctl to print the current status of datapath 0:
-
- % dpctl show 0
-
-3. (Optional) You can manually add flows to the datapath to test using
- dpctl add-flows and view them using dpctl dump-flows. See dpctl(8)
- for more details.
-
-4. The simplest way to test the datapath is to run the provided sample
- controller on the host machine to manage the datapath directly using
- netlink:
-
- % controller -v nl:0
-
- Once the controller is running, the datapath should operate like a
- learning Ethernet switch. You may monitor the flows in the datapath
- flow table using "dpctl dump-flows" command.
-
-The preceding instructions assume that the controller and the switch
-are running on the same machine. This is an easy configuration for
-testing, but a more conventional setup would run a controller on one
-machine and one or more switches on different machines. Use the
-following instructions to set up remote switches:
-
-1. Start the datapath and attach it to two or more physical ports as
- described in the previous section.
-
- Note: The current version of the switch and controller requires
- that they be connected through a "control network" that is
- physically separate from the one that they are controlling. Future
- releases will support in-band control communication.
-
-2. Run the controller in passive tcp mode on the host which will act as
- the controller. In the example below, the controller will bind to
- port 975 (the default) awaiting connections from secure channels.
-
- % controller -v ptcp:
-
- (See controller(8) for more details)
-
- Make sure the machine hosting the controller is reachable by the switch.
-
-3. Run secchan on the datapath host to start the secure channel
- connecting the datapath to a remote controller. (See secchan(8)
- for usage details). The channel should be configured to connect to
- the controller's IP address on the port configured in step 2.
-
- If the controller is running on host 192.168.1.2 port 975 (the
- default port) and the datapath ID is 0, the secchan invocation
- would look like:
-
- % secchan -v nl:0 tcp:192.168.1.2
-
Bug Reporting
-------------