1 How to Install Open vSwitch on Linux, FreeBSD and NetBSD
2 ========================================================
4 This document describes how to build and install Open vSwitch on a
5 generic Linux, FreeBSD, or NetBSD host. For specifics around installation
6 on a specific platform, please see one of these files:
16 To compile the userspace programs in the Open vSwitch distribution,
17 you will need the following software:
21 - The GNU C compiler. We generally test with version 4.1, 4.2, or
24 - libssl, from OpenSSL, is optional but recommended if you plan to
25 connect the Open vSwitch to an OpenFlow controller. libssl is
26 required to establish confidentiality and authenticity in the
27 connections from an Open vSwitch to an OpenFlow controller. If
28 libssl is installed, then Open vSwitch will automatically build
31 To compile the kernel module on Linux, you must also install the
32 following. If you cannot build or install the kernel module, you may
33 use the userspace-only implementation, at a cost in performance. The
34 userspace implementation may also lack some features. Refer to
35 INSTALL.userspace for more information.
37 - A supported Linux kernel version. Please refer to README for a
38 list of supported versions.
40 The Open vSwitch datapath requires bridging support
41 (CONFIG_BRIDGE) to be built as a kernel module. (This is common
42 in kernels provided by Linux distributions.) The bridge module
43 must not be loaded or in use. If the bridge module is running
44 (check with "lsmod | grep bridge"), you must remove it ("rmmod
45 bridge") before starting the datapath.
47 For optional support of ingress policing, you must enable kernel
48 configuration options NET_CLS_BASIC, NET_SCH_INGRESS, and
49 NET_ACT_POLICE, either built-in or as modules. (NET_CLS_POLICE is
50 obsolete and not needed.)
52 To use GRE tunneling on Linux 2.6.37 or newer, kernel support
53 for GRE must be compiled in or available as a module
54 (CONFIG_NET_IPGRE_DEMUX).
56 To configure HTB or HFSC quality of service with Open vSwitch,
57 you must enable the respective configuration options.
59 To use Open vSwitch support for TAP devices, you must enable
62 - To build a kernel module, you need the same version of GCC that
63 was used to build that kernel.
65 - A kernel build directory corresponding to the Linux kernel image
66 the module is to run on. Under Debian and Ubuntu, for example,
67 each linux-image package containing a kernel binary has a
68 corresponding linux-headers package with the required build
71 If you are working from a Git tree or snapshot (instead of from a
72 distribution tarball), or if you modify the Open vSwitch build system
73 or the database schema, you will also need the following software:
75 - Autoconf version 2.64 or later.
77 - Automake version 1.10 or later.
79 - Python 2.x, for x >= 4.
81 If you modify the ovsdbmonitor tool, then you will also need the
84 - pyuic4 from PyQt4 (http://www.riverbankcomputing.co.uk).
86 To run the unit tests, you also need:
88 - Perl. Version 5.10.1 is known to work. Earlier versions should
91 If you modify the vswitchd database schema, then the E-R diagram in
92 the ovs-vswitchd.conf.db(5) manpage will be updated properly only if
93 you have the following:
95 - "dot" from graphviz (http://www.graphviz.org/).
97 - Perl. Version 5.10.1 is known to work. Earlier versions should
100 - Python 2.x, for x >= 4.
102 If you are going to extensively modify Open vSwitch, please consider
103 installing the following to obtain better warnings:
105 - "sparse" version 0.4.4 or later
106 (http://www.kernel.org/pub/software/devel/sparse/dist/).
110 Also, you may find the ovs-dev script found in utilities/ovs-dev.py useful.
112 Installation Requirements
113 -------------------------
115 The machine on which Open vSwitch is to be installed must have the
118 - libc compatible with the libc used for build.
120 - libssl compatible with the libssl used for build, if OpenSSL was
123 - On Linux, the same kernel version configured as part of the build.
125 - For optional support of ingress policing on Linux, the "tc" program
126 from iproute2 (part of all major distributions and available at
127 http://www.linux-foundation.org/en/Net:Iproute2).
129 On Linux you should ensure that /dev/urandom exists. To support TAP
130 devices, you must also ensure that /dev/net/tun exists.
132 To run the ovsdbmonitor tool, the machine must also have the following
135 - Python 2.x, for x >= 4.
137 - Python Twisted Conch.
143 - Python Zope interface module.
145 (On Debian "lenny" the above can be installed with "apt-get install
146 python-json python-qt4 python-zopeinterface python-twisted-conch".)
148 Building and Installing Open vSwitch for Linux, FreeBSD or NetBSD
149 =================================================================
151 Once you have installed all the prerequisites listed above in the Base
152 Prerequisites section, follow the procedure below to build.
154 1. If you pulled the sources directly from an Open vSwitch Git tree,
155 run boot.sh in the top source directory:
159 2. In the top source directory, configure the package by running the
160 configure script. You can usually invoke configure without any
165 By default all files are installed under /usr/local. If you want
166 to install into, e.g., /usr and /var instead of /usr/local and
167 /usr/local/var, add options as shown here:
169 % ./configure --prefix=/usr --localstatedir=/var
171 To use a specific C compiler for compiling Open vSwitch user
172 programs, also specify it on the configure command line, like so:
174 % ./configure CC=gcc-4.2
176 To build the Linux kernel module, so that you can run the
177 kernel-based switch, pass the location of the kernel build
178 directory on --with-linux. For example, to build for a running
181 % ./configure --with-linux=/lib/modules/`uname -r`/build
183 If you wish to build the kernel module for an architecture other
184 than the architecture of the machine used for the build, you may
185 specify the kernel architecture string using the KARCH variable
186 when invoking the configure script. For example, to build for MIPS
189 % ./configure --with-linux=/path/to/linux KARCH=mips
191 The configure script accepts a number of other options and honors
192 additional environment variables. For a full list, invoke
193 configure with the --help option.
195 3. Run GNU make in the top source directory, e.g.:
199 or if GNU make is installed as "gmake":
203 For improved warnings if you installed "sparse" (see
204 "Prerequisites"), add C=1 to the command line.
206 4. Consider running the testsuite. Refer to "Running the Testsuite"
207 below, for instructions.
209 5. Become root by running "su" or another program.
211 6. Run "make install" to install the executables and manpages into the
212 running system, by default under /usr/local.
214 7. If you built kernel modules, you may install and load them, e.g.:
216 % make modules_install
217 % /sbin/modprobe openvswitch
219 To verify that the modules have been loaded, run "/sbin/lsmod" and
220 check that openvswitch is listed.
222 If the "modprobe" operation fails, look at the last few kernel log
223 messages (e.g. with "dmesg | tail"):
225 - The message "openvswitch: exports duplicate symbol
226 br_should_route_hook (owned by bridge)" means that the bridge
227 module is loaded. Run "/sbin/rmmod bridge" to remove it.
229 If "/sbin/rmmod bridge" fails with "ERROR: Module bridge does
230 not exist in /proc/modules", then the bridge is compiled into
231 the kernel, rather than as a module. Open vSwitch does not
232 support this configuration (see "Build Requirements", above).
234 - The message "openvswitch: exports duplicate symbol
235 dp_ioctl_hook (owned by ofdatapath)" means that the ofdatapath
236 module from the OpenFlow reference implementation is loaded.
237 Run "/sbin/rmmod ofdatapath" to remove it. (You might have to
238 delete any existing datapaths beforehand, using the "dpctl"
239 program included with the OpenFlow reference implementation.
240 "ovs-dpctl" will not work.)
242 - Otherwise, the most likely problem is that Open vSwitch was
243 built for a kernel different from the one into which you are
244 trying to load it. Run "modinfo" on openvswitch.ko and on
245 a module built for the running kernel, e.g.:
247 % /sbin/modinfo openvswitch.ko
248 % /sbin/modinfo /lib/modules/`uname -r`/kernel/net/bridge/bridge.ko
250 Compare the "vermagic" lines output by the two commands. If
251 they differ, then Open vSwitch was built for the wrong kernel.
253 - If you decide to report a bug or ask a question related to
254 module loading, please include the output from the "dmesg" and
255 "modinfo" commands mentioned above.
257 There is an optional module parameter to openvswitch.ko called
258 vlan_tso that enables TCP segmentation offload over VLANs on NICs
259 that support it. Many drivers do not expose support for TSO on VLANs
260 in a way that Open vSwitch can use but there is no way to detect
261 whether this is the case. If you know that your particular driver can
262 handle it (for example by testing sending large TCP packets over VLANs)
263 then passing in a value of 1 may improve performance. Modules built for
264 Linux kernels 2.6.37 and later, as well as specially patched versions
265 of earlier kernels, do not need this and do not have this parameter. If
266 you do not understand what this means or do not know if your driver
267 will work, do not set this.
269 8. Initialize the configuration database using ovsdb-tool, e.g.:
271 % mkdir -p /usr/local/etc/openvswitch
272 % ovsdb-tool create /usr/local/etc/openvswitch/conf.db vswitchd/vswitch.ovsschema
277 Before starting ovs-vswitchd itself, you need to start its
278 configuration database, ovsdb-server. Each machine on which Open
279 vSwitch is installed should run its own copy of ovsdb-server.
280 Configure it to use the database you created during step 7 of
281 installation, above, to listen on a Unix domain socket, to connect to
282 any managers specified in the database itself, and to use the SSL
283 configuration in the database:
285 % ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock \
286 --remote=db:Open_vSwitch,Open_vSwitch,manager_options \
287 --private-key=db:Open_vSwitch,SSL,private_key \
288 --certificate=db:Open_vSwitch,SSL,certificate \
289 --bootstrap-ca-cert=db:Open_vSwitch,SSL,ca_cert \
292 (If you built Open vSwitch without SSL support, then omit
293 --private-key, --certificate, and --bootstrap-ca-cert.)
295 Then initialize the database using ovs-vsctl. This is only
296 necessary the first time after you create the database with
297 ovsdb-tool (but running it at any time is harmless):
299 % ovs-vsctl --no-wait init
301 Then start the main Open vSwitch daemon, telling it to connect to the
302 same Unix domain socket:
304 % ovs-vswitchd --pidfile --detach
306 Now you may use ovs-vsctl to set up bridges and other Open vSwitch
307 features. For example, to create a bridge named br0 and add ports
308 eth0 and vif1.0 to it:
310 % ovs-vsctl add-br br0
311 % ovs-vsctl add-port br0 eth0
312 % ovs-vsctl add-port br0 vif1.0
314 Please refer to ovs-vsctl(8) for more details.
319 When you upgrade Open vSwitch from one version to another, you should
320 also upgrade the database schema:
322 1. Stop the Open vSwitch daemons, e.g.:
324 % kill `cd /usr/local/var/run/openvswitch && cat ovsdb-server.pid ovs-vswitchd.pid`
326 2. Install the new Open vSwitch release.
328 3. Upgrade the database, in one of the following two ways:
330 - If there is no important data in your database, then you may
331 delete the database file and recreate it with ovsdb-tool,
332 following the instructions under "Building and Installing Open
333 vSwitch for Linux, FreeBSD or NetBSD".
335 - If you want to preserve the contents of your database, back it
336 up first, then use "ovsdb-tool convert" to upgrade it, e.g.:
338 % ovsdb-tool convert /usr/local/etc/openvswitch/conf.db vswitchd/vswitch.ovsschema
340 4. Start the Open vSwitch daemons as described under "Building and
341 Installing Open vSwitch for Linux, FreeBSD or NetBSD" above.
345 Upgrading Open vSwitch from one version to the next version with minimum
346 disruption of traffic going through the system that is using that Open vSwitch
347 needs some considerations:
349 1. If the upgrade only involves upgrading the userspace utilities and daemons
350 of Open vSwitch, make sure that the new userspace version is compatible with
351 the previously loaded kernel module.
353 2. An upgrade of userspace daemons means that they have to be restarted.
354 Restarting the daemons means that the Openflow flows in the ovs-vswitchd daemon
355 will be lost. One way to restore the flows is to let the controller
356 re-populate it. Another way is to save the previous flows using a utility
357 like ovs-ofctl and then re-add them after the restart. Restoring the old flows
358 is accurate only if the new Open vSwitch interfaces retain the old 'ofport'
361 3. When the new userspace daemons get restarted, they automatically flush
362 the old flows setup in the kernel. This can be expensive if there are hundreds
363 of new flows that are entering the kernel but userspace daemons are busy
364 setting up new userspace flows from either the controller or an utility like
365 ovs-ofctl. Open vSwitch database provides an option to solve this problem
366 through the other_config:flow-restore-wait column of the Open_vSwitch table.
367 Refer to the ovs-vswitchd.conf.db(5) manpage for details.
369 4. If the upgrade also involves upgrading the kernel module, the old kernel
370 module needs to be unloaded and the new kernel module should be loaded. This
371 means that the kernel network devices belonging to Open vSwitch is recreated
372 and the kernel flows are lost. The downtime of the traffic can be reduced
373 if the userspace daemons are restarted immediately and the userspace flows
374 are restored as soon as possible.
376 The ovs-ctl utility's "restart" function only restarts the userspace daemons,
377 makes sure that the 'ofport' values remain consistent across restarts, restores
378 userspace flows using the ovs-ofctl utility and also uses the
379 other_config:flow-restore-wait column to keep the traffic downtime to the
380 minimum. The ovs-ctl utility's "force-reload-kmod" function does all of the
381 above, but also replaces the old kernel module with the new one. Open vSwitch
382 startup scripts for Debian, XenServer and RHEL use ovs-ctl's functions and it
383 is recommended that these functions be used for other software platforms too.
385 Running the Testsuite
386 =====================
388 Open vSwitch includes a testsuite. Before you submit patches
389 upstream, we advise that you run the tests and ensure that they pass.
390 If you add new features to Open vSwitch, then adding tests for those
391 features will ensure your features don't break as developers modify
392 other areas of Open vSwitch.
394 You must configure and build Open vSwitch (steps 1 through 3 in
395 "Building and Installing Open vSwitch for Linux, FreeBSD or NetBSD" above)
396 before you run the testsuite. You do not need to install Open vSwitch
397 or to build or load the kernel module to run the testsuite. You do
398 not need supervisor privilege to run the testsuite.
400 To run all the unit tests in Open vSwitch, one at a time:
402 This takes under 5 minutes on a modern desktop system.
404 To run all the unit tests in Open vSwitch, up to 8 in parallel:
405 make check TESTSUITEFLAGS=-j8
406 This takes under a minute on a modern 4-core desktop system.
408 To see a list of all the available tests, run:
409 make check TESTSUITEFLAGS=--list
411 To run only a subset of tests, e.g. test 123 and tests 477 through 484:
412 make check TESTSUITEFLAGS='123 477-484'
413 (Tests do not have inter-dependencies, so you may run any subset.)
415 To run tests matching a keyword, e.g. "ovsdb":
416 make check TESTSUITEFLAGS='-k ovsdb'
418 To see a complete list of test options:
419 make check TESTSUITEFLAGS=--help
421 The results of a testing run are reported in tests/testsuite.log.
422 Please report test failures as bugs and include the testsuite.log in
425 If you have "valgrind" installed, then you can also run the testsuite
426 under valgrind by using "make check-valgrind" in place of "make
427 check". All the same options are available via TESTSUITEFLAGS. When
428 you do this, the "valgrind" results for test <N> are reported in files
429 named tests/testsuite.dir/<N>/valgrind.*. You may find that the
430 valgrind results are easier to interpret if you put "-q" in
431 ~/.valgrindrc, since that reduces the amount of output.
433 Sometimes a few tests may fail on some runs but not others. This is
434 usually a bug in the testsuite, not a bug in Open vSwitch itself. If
435 you find that a test fails intermittently, please report it, since the
436 developers may not have noticed.
441 Please report problems to bugs@openvswitch.org.