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 - A C compiler, such as:
25 * Clang. Clang 3.4 and later provide useful static semantic
26 analysis and thread-safety checks. For Ubuntu, there are
27 nightly built packages available on clang's website.
29 - libssl, from OpenSSL, is optional but recommended if you plan to
30 connect the Open vSwitch to an OpenFlow controller. libssl is
31 required to establish confidentiality and authenticity in the
32 connections from an Open vSwitch to an OpenFlow controller. If
33 libssl is installed, then Open vSwitch will automatically build
36 - Python 2.x, for x >= 4.
38 To compile the kernel module on Linux, you must also install the
39 following. If you cannot build or install the kernel module, you may
40 use the userspace-only implementation, at a cost in performance. The
41 userspace implementation may also lack some features. Refer to
42 INSTALL.userspace for more information.
44 - A supported Linux kernel version. Please refer to README for a
45 list of supported versions.
47 The Open vSwitch datapath requires bridging support
48 (CONFIG_BRIDGE) to be built as a kernel module. (This is common
49 in kernels provided by Linux distributions.) The bridge module
50 must not be loaded or in use. If the bridge module is running
51 (check with "lsmod | grep bridge"), you must remove it ("rmmod
52 bridge") before starting the datapath.
54 For optional support of ingress policing, you must enable kernel
55 configuration options NET_CLS_BASIC, NET_SCH_INGRESS, and
56 NET_ACT_POLICE, either built-in or as modules. (NET_CLS_POLICE is
57 obsolete and not needed.)
59 To use GRE tunneling on Linux 2.6.37 or newer, kernel support
60 for GRE must be compiled in or available as a module
61 (CONFIG_NET_IPGRE_DEMUX).
63 To configure HTB or HFSC quality of service with Open vSwitch,
64 you must enable the respective configuration options.
66 To use Open vSwitch support for TAP devices, you must enable
69 - To build a kernel module, you need the same version of GCC that
70 was used to build that kernel.
72 - A kernel build directory corresponding to the Linux kernel image
73 the module is to run on. Under Debian and Ubuntu, for example,
74 each linux-image package containing a kernel binary has a
75 corresponding linux-headers package with the required build
78 If you are working from a Git tree or snapshot (instead of from a
79 distribution tarball), or if you modify the Open vSwitch build system
80 or the database schema, you will also need the following software:
82 - Autoconf version 2.64 or later.
84 - Automake version 1.10 or later.
86 - libtool version 2.4 or later. (Older versions might work too.)
88 If you modify the ovsdbmonitor tool, then you will also need the
91 - pyuic4 from PyQt4 (http://www.riverbankcomputing.co.uk).
93 To run the unit tests, you also need:
95 - Perl. Version 5.10.1 is known to work. Earlier versions should
98 The ovs-vswitchd.conf.db(5) manpage will include an E-R diagram, in
99 formats other than plain text, only if you have the following:
101 - "dot" from graphviz (http://www.graphviz.org/).
103 - Perl. Version 5.10.1 is known to work. Earlier versions should
106 - Python 2.x, for x >= 4.
108 If you are going to extensively modify Open vSwitch, please consider
109 installing the following to obtain better warnings:
111 - "sparse" version 0.4.4 or later
112 (http://www.kernel.org/pub/software/devel/sparse/dist/).
116 - clang, version 3.4 or later
118 Also, you may find the ovs-dev script found in utilities/ovs-dev.py useful.
120 Installation Requirements
121 -------------------------
123 The machine on which Open vSwitch is to be installed must have the
126 - libc compatible with the libc used for build.
128 - libssl compatible with the libssl used for build, if OpenSSL was
131 - On Linux, the same kernel version configured as part of the build.
133 - For optional support of ingress policing on Linux, the "tc" program
134 from iproute2 (part of all major distributions and available at
135 http://www.linux-foundation.org/en/Net:Iproute2).
137 On Linux you should ensure that /dev/urandom exists. To support TAP
138 devices, you must also ensure that /dev/net/tun exists.
140 To run the ovsdbmonitor tool, the machine must also have the following
143 - Python 2.x, for x >= 4.
145 - Python Twisted Conch.
151 - Python Zope interface module.
153 (On Debian "lenny" the above can be installed with "apt-get install
154 python-json python-qt4 python-zopeinterface python-twisted-conch".)
156 Building and Installing Open vSwitch for Linux, FreeBSD or NetBSD
157 =================================================================
159 Once you have installed all the prerequisites listed above in the Base
160 Prerequisites section, follow the procedure below to build.
162 1. If you pulled the sources directly from an Open vSwitch Git tree,
163 run boot.sh in the top source directory:
167 2. In the top source directory, configure the package by running the
168 configure script. You can usually invoke configure without any
173 By default all files are installed under /usr/local. If you want
174 to install into, e.g., /usr and /var instead of /usr/local and
175 /usr/local/var, add options as shown here:
177 % ./configure --prefix=/usr --localstatedir=/var
179 To use a specific C compiler for compiling Open vSwitch user
180 programs, also specify it on the configure command line, like so:
182 % ./configure CC=gcc-4.2
184 To use 'clang' compiler:
186 % ./configure CC=clang
188 To build the Linux kernel module, so that you can run the
189 kernel-based switch, pass the location of the kernel build
190 directory on --with-linux. For example, to build for a running
193 % ./configure --with-linux=/lib/modules/`uname -r`/build
195 If you wish to build the kernel module for an architecture other
196 than the architecture of the machine used for the build, you may
197 specify the kernel architecture string using the KARCH variable
198 when invoking the configure script. For example, to build for MIPS
201 % ./configure --with-linux=/path/to/linux KARCH=mips
203 If you plan to do much Open vSwitch development, you might want to
204 add --enable-Werror, which adds the -Werror option to the compiler
205 command line, turning warnings into errors. That makes it
206 impossible to miss warnings generated by the build.
208 The configure script accepts a number of other options and honors
209 additional environment variables. For a full list, invoke
210 configure with the --help option.
212 3. Run GNU make in the top source directory, e.g.:
216 or if GNU make is installed as "gmake":
220 For improved warnings if you installed "sparse" (see
221 "Prerequisites"), add C=1 to the command line.
223 4. Consider running the testsuite. Refer to "Running the Testsuite"
224 below, for instructions.
226 5. Become root by running "su" or another program.
228 6. Run "make install" to install the executables and manpages into the
229 running system, by default under /usr/local.
231 7. If you built kernel modules, you may install and load them, e.g.:
233 % make modules_install
234 % /sbin/modprobe openvswitch
236 To verify that the modules have been loaded, run "/sbin/lsmod" and
237 check that openvswitch is listed.
239 If the "modprobe" operation fails, look at the last few kernel log
240 messages (e.g. with "dmesg | tail"):
242 - The message "openvswitch: exports duplicate symbol
243 br_should_route_hook (owned by bridge)" means that the bridge
244 module is loaded. Run "/sbin/rmmod bridge" to remove it.
246 If "/sbin/rmmod bridge" fails with "ERROR: Module bridge does
247 not exist in /proc/modules", then the bridge is compiled into
248 the kernel, rather than as a module. Open vSwitch does not
249 support this configuration (see "Build Requirements", above).
251 - The message "openvswitch: exports duplicate symbol
252 dp_ioctl_hook (owned by ofdatapath)" means that the ofdatapath
253 module from the OpenFlow reference implementation is loaded.
254 Run "/sbin/rmmod ofdatapath" to remove it. (You might have to
255 delete any existing datapaths beforehand, using the "dpctl"
256 program included with the OpenFlow reference implementation.
257 "ovs-dpctl" will not work.)
259 - Otherwise, the most likely problem is that Open vSwitch was
260 built for a kernel different from the one into which you are
261 trying to load it. Run "modinfo" on openvswitch.ko and on
262 a module built for the running kernel, e.g.:
264 % /sbin/modinfo openvswitch.ko
265 % /sbin/modinfo /lib/modules/`uname -r`/kernel/net/bridge/bridge.ko
267 Compare the "vermagic" lines output by the two commands. If
268 they differ, then Open vSwitch was built for the wrong kernel.
270 - If you decide to report a bug or ask a question related to
271 module loading, please include the output from the "dmesg" and
272 "modinfo" commands mentioned above.
274 There is an optional module parameter to openvswitch.ko called
275 vlan_tso that enables TCP segmentation offload over VLANs on NICs
276 that support it. Many drivers do not expose support for TSO on VLANs
277 in a way that Open vSwitch can use but there is no way to detect
278 whether this is the case. If you know that your particular driver can
279 handle it (for example by testing sending large TCP packets over VLANs)
280 then passing in a value of 1 may improve performance. Modules built for
281 Linux kernels 2.6.37 and later, as well as specially patched versions
282 of earlier kernels, do not need this and do not have this parameter. If
283 you do not understand what this means or do not know if your driver
284 will work, do not set this.
286 8. Initialize the configuration database using ovsdb-tool, e.g.:
288 % mkdir -p /usr/local/etc/openvswitch
289 % ovsdb-tool create /usr/local/etc/openvswitch/conf.db vswitchd/vswitch.ovsschema
294 Before starting ovs-vswitchd itself, you need to start its
295 configuration database, ovsdb-server. Each machine on which Open
296 vSwitch is installed should run its own copy of ovsdb-server.
297 Configure it to use the database you created during step 7 of
298 installation, above, to listen on a Unix domain socket, to connect to
299 any managers specified in the database itself, and to use the SSL
300 configuration in the database:
302 % ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock \
303 --remote=db:Open_vSwitch,Open_vSwitch,manager_options \
304 --private-key=db:Open_vSwitch,SSL,private_key \
305 --certificate=db:Open_vSwitch,SSL,certificate \
306 --bootstrap-ca-cert=db:Open_vSwitch,SSL,ca_cert \
309 (If you built Open vSwitch without SSL support, then omit
310 --private-key, --certificate, and --bootstrap-ca-cert.)
312 Then initialize the database using ovs-vsctl. This is only
313 necessary the first time after you create the database with
314 ovsdb-tool (but running it at any time is harmless):
316 % ovs-vsctl --no-wait init
318 Then start the main Open vSwitch daemon, telling it to connect to the
319 same Unix domain socket:
321 % ovs-vswitchd --pidfile --detach
323 Now you may use ovs-vsctl to set up bridges and other Open vSwitch
324 features. For example, to create a bridge named br0 and add ports
325 eth0 and vif1.0 to it:
327 % ovs-vsctl add-br br0
328 % ovs-vsctl add-port br0 eth0
329 % ovs-vsctl add-port br0 vif1.0
331 Please refer to ovs-vsctl(8) for more details.
336 When you upgrade Open vSwitch from one version to another, you should
337 also upgrade the database schema:
339 1. Stop the Open vSwitch daemons, e.g.:
341 % kill `cd /usr/local/var/run/openvswitch && cat ovsdb-server.pid ovs-vswitchd.pid`
343 2. Install the new Open vSwitch release.
345 3. Upgrade the database, in one of the following two ways:
347 - If there is no important data in your database, then you may
348 delete the database file and recreate it with ovsdb-tool,
349 following the instructions under "Building and Installing Open
350 vSwitch for Linux, FreeBSD or NetBSD".
352 - If you want to preserve the contents of your database, back it
353 up first, then use "ovsdb-tool convert" to upgrade it, e.g.:
355 % ovsdb-tool convert /usr/local/etc/openvswitch/conf.db vswitchd/vswitch.ovsschema
357 4. Start the Open vSwitch daemons as described under "Building and
358 Installing Open vSwitch for Linux, FreeBSD or NetBSD" above.
362 Upgrading Open vSwitch from one version to the next version with minimum
363 disruption of traffic going through the system that is using that Open vSwitch
364 needs some considerations:
366 1. If the upgrade only involves upgrading the userspace utilities and daemons
367 of Open vSwitch, make sure that the new userspace version is compatible with
368 the previously loaded kernel module.
370 2. An upgrade of userspace daemons means that they have to be restarted.
371 Restarting the daemons means that the Openflow flows in the ovs-vswitchd daemon
372 will be lost. One way to restore the flows is to let the controller
373 re-populate it. Another way is to save the previous flows using a utility
374 like ovs-ofctl and then re-add them after the restart. Restoring the old flows
375 is accurate only if the new Open vSwitch interfaces retain the old 'ofport'
378 3. When the new userspace daemons get restarted, they automatically flush
379 the old flows setup in the kernel. This can be expensive if there are hundreds
380 of new flows that are entering the kernel but userspace daemons are busy
381 setting up new userspace flows from either the controller or an utility like
382 ovs-ofctl. Open vSwitch database provides an option to solve this problem
383 through the other_config:flow-restore-wait column of the Open_vSwitch table.
384 Refer to the ovs-vswitchd.conf.db(5) manpage for details.
386 4. If the upgrade also involves upgrading the kernel module, the old kernel
387 module needs to be unloaded and the new kernel module should be loaded. This
388 means that the kernel network devices belonging to Open vSwitch is recreated
389 and the kernel flows are lost. The downtime of the traffic can be reduced
390 if the userspace daemons are restarted immediately and the userspace flows
391 are restored as soon as possible.
393 The ovs-ctl utility's "restart" function only restarts the userspace daemons,
394 makes sure that the 'ofport' values remain consistent across restarts, restores
395 userspace flows using the ovs-ofctl utility and also uses the
396 other_config:flow-restore-wait column to keep the traffic downtime to the
397 minimum. The ovs-ctl utility's "force-reload-kmod" function does all of the
398 above, but also replaces the old kernel module with the new one. Open vSwitch
399 startup scripts for Debian, XenServer and RHEL use ovs-ctl's functions and it
400 is recommended that these functions be used for other software platforms too.
402 Running the Testsuite
403 =====================
405 Open vSwitch includes a testsuite. Before you submit patches
406 upstream, we advise that you run the tests and ensure that they pass.
407 If you add new features to Open vSwitch, then adding tests for those
408 features will ensure your features don't break as developers modify
409 other areas of Open vSwitch.
411 You must configure and build Open vSwitch (steps 1 through 3 in
412 "Building and Installing Open vSwitch for Linux, FreeBSD or NetBSD" above)
413 before you run the testsuite. You do not need to install Open vSwitch
414 or to build or load the kernel module to run the testsuite. You do
415 not need supervisor privilege to run the testsuite.
417 To run all the unit tests in Open vSwitch, one at a time:
419 This takes under 5 minutes on a modern desktop system.
421 To run all the unit tests in Open vSwitch, up to 8 in parallel:
422 make check TESTSUITEFLAGS=-j8
423 This takes under a minute on a modern 4-core desktop system.
425 To see a list of all the available tests, run:
426 make check TESTSUITEFLAGS=--list
428 To run only a subset of tests, e.g. test 123 and tests 477 through 484:
429 make check TESTSUITEFLAGS='123 477-484'
430 (Tests do not have inter-dependencies, so you may run any subset.)
432 To run tests matching a keyword, e.g. "ovsdb":
433 make check TESTSUITEFLAGS='-k ovsdb'
435 To see a complete list of test options:
436 make check TESTSUITEFLAGS=--help
438 The results of a testing run are reported in tests/testsuite.log.
439 Please report test failures as bugs and include the testsuite.log in
442 If you have "valgrind" installed, then you can also run the testsuite
443 under valgrind by using "make check-valgrind" in place of "make
444 check". All the same options are available via TESTSUITEFLAGS. When
445 you do this, the "valgrind" results for test <N> are reported in files
446 named tests/testsuite.dir/<N>/valgrind.*. You may find that the
447 valgrind results are easier to interpret if you put "-q" in
448 ~/.valgrindrc, since that reduces the amount of output.
450 Sometimes a few tests may fail on some runs but not others. This is
451 usually a bug in the testsuite, not a bug in Open vSwitch itself. If
452 you find that a test fails intermittently, please report it, since the
453 developers may not have noticed.
458 Please report problems to bugs@openvswitch.org.