1 How to Install Open vSwitch on Linux
2 ====================================
4 This document describes how to build and install Open vSwitch on a
5 generic Linux host. If you want to install Open vSwitch on a Citrix
6 XenServer, see INSTALL.XenServer instead.
8 This version of Open vSwitch may be built manually with "configure"
9 and "make", as described below. You may also build Debian packages by
10 running "dpkg-buildpackage".
15 To compile the userspace programs in the Open vSwitch distribution,
16 you will need the following software:
18 - A make program, e.g. GNU make. BSD make should also work.
20 - The GNU C compiler. We generally test with version 4.1, 4.2, or
23 - pkg-config. We test with version 0.22.
25 - libssl, from OpenSSL, is optional but recommended if you plan to
26 connect the Open vSwitch to an OpenFlow controller. libssl is
27 required to establish confidentiality and authenticity in the
28 connections from an Open vSwitch to an OpenFlow controller. If
29 libssl is installed, then Open vSwitch will automatically build
32 To compile the kernel module, you must also install the following. If
33 you cannot build or install the kernel module, you may use the
34 userspace-only implementation, at a cost in performance. The
35 userspace implementation may also lack some features. Refer to
36 INSTALL.userspace for more information.
38 - A supported Linux kernel version. Please refer to README for a
39 list of supported versions.
41 The Open vSwitch datapath requires bridging support
42 (CONFIG_BRIDGE) to be built as a kernel module. (This is common
43 in kernels provided by Linux distributions.) The bridge module
44 must not be loaded or in use. If the bridge module is running
45 (check with "lsmod | grep bridge"), you must remove it ("rmmod
46 bridge") before starting the datapath.
48 For optional support of ingress policing, you must enable kernel
49 configuration options NET_CLS_BASIC, NET_SCH_INGRESS, and
50 NET_ACT_POLICE, either built-in or as modules. (NET_CLS_POLICE is
51 obsolete and not needed.)
53 If GRE tunneling is being used it is recommended that the kernel
54 be compiled with IPv6 support (CONFIG_IPV6). This allows for
55 special handling (such as path MTU discovery) of IPv6 packets.
57 To configure HTB or HFSC quality of service with Open vSwitch,
58 you must enable the respective configuration options.
60 To use Open vSwitch support for TAP devices, you must enable
63 - To build a kernel module, you need the same version of GCC that
64 was used to build that kernel.
66 - A kernel build directory corresponding to the Linux kernel image
67 the module is to run on. Under Debian and Ubuntu, for example,
68 each linux-image package containing a kernel binary has a
69 corresponding linux-headers package with the required build
72 If you are working from a Git tree or snapshot (instead of from a
73 distribution tarball), or if you modify the Open vSwitch build system
74 or the database schema, you will also need the following software:
76 - Autoconf version 2.64 or later.
78 - Automake version 1.10 or later.
80 - Python 2.x, for x >= 4.
82 If you modify the ovsdbmonitor tool, then you will also need the
85 - pyuic4 from PyQt4 (http://www.riverbankcomputing.co.uk).
87 To run the unit tests, you also need:
89 - Perl. Version 5.10.1 is known to work. Earlier versions should
92 If you modify the vswitchd database schema, then the E-R diagram in
93 the ovs-vswitchd.conf.db(5) manpage will be updated properly only if
94 you have the following:
96 - "dot" from graphviz (http://www.graphviz.org/).
98 - Perl. Version 5.10.1 is known to work. Earlier versions should
101 - Python 2.x, for x >= 4.
103 If you are going to extensively modify Open vSwitch, please consider
104 installing the following to obtain better warnings:
106 - "sparse" version 0.4.4 or later
107 (http://www.kernel.org/pub/software/devel/sparse/dist/).
111 Installation Requirements
112 -------------------------
114 The machine on which Open vSwitch is to be installed must have the
117 - libc compatible with the libc used for build.
119 - libssl compatible with the libssl used for build, if OpenSSL was
122 - The Linux kernel version configured as part of the build.
124 - For optional support of ingress policing, the "tc" program from
125 iproute2 (part of all major distributions and available at
126 http://www.linux-foundation.org/en/Net:Iproute2).
128 You should ensure that /dev/urandom exists. To support TAP devices,
129 you must also ensure that /dev/net/tun exists.
131 To run the ovsdbmonitor tool, the machine must also have the following
134 - Python 2.x, for x >= 4.
136 - Python Twisted Conch.
142 - Python Zope interface module.
144 (On Debian "lenny" the above can be installed with "apt-get install
145 python-json python-qt4 python-zopeinterface python-twisted-conch".)
147 Building and Installing Open vSwitch for Linux
148 ==============================================
150 Once you have installed all the prerequisites listed above in the Base
151 Prerequisites section, follow the procedure below to build.
153 1. If you pulled the sources directly from an Open vSwitch Git tree,
154 run boot.sh in the top source directory:
158 2. In the top source directory, configure the package by running the
159 configure script. You can usually invoke configure without any
164 By default all files are installed under /usr/local. If you want
165 to install into, e.g., /usr and /var instead of /usr/local and
166 /usr/local/var, add options as shown here:
168 % ./configure --prefix=/usr --localstatedir=/var
170 To use a specific C compiler for compiling Open vSwitch user
171 programs, also specify it on the configure command line, like so:
173 % ./configure CC=gcc-4.2
175 To build the Linux kernel module, so that you can run the
176 kernel-based switch, pass the location of the kernel build
177 directory on --with-linux. For example, to build for a running
180 % ./configure --with-linux=/lib/modules/`uname -r`/build
182 If you wish to build the kernel module for an architecture other
183 than the architecture of the machine used for the build, you may
184 specify the kernel architecture string using the KARCH variable
185 when invoking the configure script. For example, to build for MIPS
188 % ./configure --with-linux=/path/to/linux KARCH=mips
190 The configure script accepts a number of other options and honors
191 additional environment variables. For a full list, invoke
192 configure with the --help option.
194 3. Run make in the top source directory:
198 For improved warnings if you installed "sparse" (see
199 "Prerequisites"), add C=1 to the "make" command line.
201 4. Become root by running "su" or another program.
203 5. Run "make install" to install the executables and manpages into the
204 running system, by default under /usr/local.
206 6. If you built kernel modules, you may load them with "insmod", e.g.:
208 % insmod datapath/linux/openvswitch.ko
210 You may need to specify a full path to insmod, e.g. /sbin/insmod.
211 To verify that the modules have been loaded, run "/sbin/lsmod" and
212 check that openvswitch is listed.
214 If the "insmod" operation fails, look at the last few kernel log
215 messages (e.g. with "dmesg | tail"):
217 - The message "openvswitch: exports duplicate symbol
218 br_should_route_hook (owned by bridge)" means that the bridge
219 module is loaded. Run "/sbin/rmmod bridge" to remove it.
221 If "/sbin/rmmod bridge" fails with "ERROR: Module bridge does
222 not exist in /proc/modules", then the bridge is compiled into
223 the kernel, rather than as a module. Open vSwitch does not
224 support this configuration (see "Build Requirements", above).
226 - The message "openvswitch: exports duplicate symbol
227 dp_ioctl_hook (owned by ofdatapath)" means that the ofdatapath
228 module from the OpenFlow reference implementation is loaded.
229 Run "/sbin/rmmod ofdatapath" to remove it. (You might have to
230 delete any existing datapaths beforehand, using the "dpctl"
231 program included with the OpenFlow reference implementation.
232 "ovs-dpctl" will not work.)
234 - Otherwise, the most likely problem is that Open vSwitch was
235 built for a kernel different from the one into which you are
236 trying to load it. Run "modinfo" on openvswitch.ko and on
237 a module built for the running kernel, e.g.:
239 % /sbin/modinfo openvswitch.ko
240 % /sbin/modinfo /lib/modules/`uname -r`/kernel/net/bridge/bridge.ko
242 Compare the "vermagic" lines output by the two commands. If
243 they differ, then Open vSwitch was built for the wrong kernel.
245 - If you decide to report a bug or ask a question related to
246 module loading, please include the output from the "dmesg" and
247 "modinfo" commands mentioned above.
249 There is an optional module parameter to openvswitch.ko called
250 vlan_tso that enables TCP segmentation offload over VLANs on NICs
251 that support it. Many drivers do not expose support for TSO on VLANs
252 in a way that Open vSwitch can use but there is no way to detect
253 whether this is the case. If you know that your particular driver can
254 handle it (for example by testing sending large TCP packets over VLANs)
255 then passing in a value of 1 may improve performance. Modules built for
256 Linux kernels 2.6.37 and later, as well as specially patched versions
257 of earlier kernels, do not need this and do not have this parameter. If
258 you do not understand what this means or do not know if your driver
259 will work, do not set this.
261 7. Initialize the configuration database using ovsdb-tool, e.g.:
263 % mkdir -p /usr/local/etc/openvswitch
264 % ovsdb-tool create /usr/local/etc/openvswitch/conf.db vswitchd/vswitch.ovsschema
269 Before starting ovs-vswitchd itself, you need to start its
270 configuration database, ovsdb-server. Each machine on which Open
271 vSwitch is installed should run its own copy of ovsdb-server.
272 Configure it to use the database you created during step 7 of
273 installation, above, to listen on a Unix domain socket, to connect to
274 any managers specified in the database itself, and to use the SSL
275 configuration in the database:
277 % ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock \
278 --remote=db:Open_vSwitch,manager_options \
279 --private-key=db:SSL,private_key \
280 --certificate=db:SSL,certificate \
281 --bootstrap-ca-cert=db:SSL,ca_cert \
284 (If you built Open vSwitch without SSL support, then omit
285 --private-key, --certificate, and --bootstrap-ca-cert.)
287 Then initialize the database using ovs-vsctl. This is only
288 necessary the first time after you create the database with
289 ovsdb-tool (but running it at any time is harmless):
291 % ovs-vsctl --no-wait init
293 Then start the main Open vSwitch daemon, telling it to connect to the
294 same Unix domain socket:
296 % ovs-vswitchd --pidfile --detach
298 Now you may use ovs-vsctl to set up bridges and other Open vSwitch
299 features. For example, to create a bridge named br0 and add ports
300 eth0 and vif1.0 to it:
302 % ovs-vsctl add-br br0
303 % ovs-vsctl add-port br0 eth0
304 % ovs-vsctl add-port br0 vif1.0
306 Please refer to ovs-vsctl(8) for more details.
311 When you upgrade Open vSwitch from one version to another, you should
312 also upgrade the database schema:
314 1. Stop the Open vSwitch daemons, e.g.:
316 % kill `cd /usr/local/var/run/openvswitch && cat ovsdb-server.pid ovs-vswitchd.pid`
318 2. Install the new Open vSwitch release.
320 3. Upgrade the database, in one of the following two ways:
322 - If there is no important data in your database, then you may
323 delete the database file and recreate it with ovsdb-tool,
324 following the instructions under "Building and Installing Open
327 - If you want to preserve the contents of your database, back it
328 up first, then use "ovsdb-tool convert" to upgrade it, e.g.:
330 % ovsdb-tool convert /usr/local/etc/openvswitch/conf.db vswitchd/vswitch.ovsschema
332 4. Start the Open vSwitch daemons as described under "Building and
333 Installing Open vSwitch for Linux" above.
338 Please report problems to bugs@openvswitch.org.