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:
17 To compile the userspace programs in the Open vSwitch distribution,
18 you will need the following software:
22 - A C compiler, such as:
26 * Clang. Clang 3.4 and later provide useful static semantic
27 analysis and thread-safety checks. For Ubuntu, there are
28 nightly built packages available on clang's website.
30 - libssl, from OpenSSL, is optional but recommended if you plan to
31 connect the Open vSwitch to an OpenFlow controller. libssl is
32 required to establish confidentiality and authenticity in the
33 connections from an Open vSwitch to an OpenFlow controller. If
34 libssl is installed, then Open vSwitch will automatically build
37 - Python 2.x, for x >= 4.
39 To compile the kernel module on Linux, you must also install the
40 following. If you cannot build or install the kernel module, you may
41 use the userspace-only implementation, at a cost in performance. The
42 userspace implementation may also lack some features. Refer to
43 INSTALL.userspace for more information.
45 - A supported Linux kernel version. Please refer to README for a
46 list of supported versions.
48 The Open vSwitch datapath requires bridging support
49 (CONFIG_BRIDGE) to be built as a kernel module. (This is common
50 in kernels provided by Linux distributions.) The bridge module
51 must not be loaded or in use. If the bridge module is running
52 (check with "lsmod | grep bridge"), you must remove it ("rmmod
53 bridge") before starting the datapath.
55 For optional support of ingress policing, you must enable kernel
56 configuration options NET_CLS_BASIC, NET_SCH_INGRESS, and
57 NET_ACT_POLICE, either built-in or as modules. (NET_CLS_POLICE is
58 obsolete and not needed.)
60 To use GRE tunneling on Linux 2.6.37 or newer, kernel support
61 for GRE must be compiled in or available as a module
62 (CONFIG_NET_IPGRE_DEMUX).
64 To configure HTB or HFSC quality of service with Open vSwitch,
65 you must enable the respective configuration options.
67 To use Open vSwitch support for TAP devices, you must enable
70 - To build a kernel module, you need the same version of GCC that
71 was used to build that kernel.
73 - A kernel build directory corresponding to the Linux kernel image
74 the module is to run on. Under Debian and Ubuntu, for example,
75 each linux-image package containing a kernel binary has a
76 corresponding linux-headers package with the required build
79 If you are working from a Git tree or snapshot (instead of from a
80 distribution tarball), or if you modify the Open vSwitch build system
81 or the database schema, you will also need the following software:
83 - Autoconf version 2.64 or later.
85 - Automake version 1.10 or later.
87 - libtool version 2.4 or later. (Older versions might work too.)
89 If you modify the ovsdbmonitor tool, then you will also need the
92 - pyuic4 from PyQt4 (http://www.riverbankcomputing.co.uk).
94 To run the unit tests, you also need:
96 - Perl. Version 5.10.1 is known to work. Earlier versions should
99 The ovs-vswitchd.conf.db(5) manpage will include an E-R diagram, in
100 formats other than plain text, only if you have the following:
102 - "dot" from graphviz (http://www.graphviz.org/).
104 - Perl. Version 5.10.1 is known to work. Earlier versions should
107 - Python 2.x, for x >= 4.
109 If you are going to extensively modify Open vSwitch, please consider
110 installing the following to obtain better warnings:
112 - "sparse" version 0.4.4 or later
113 (http://www.kernel.org/pub/software/devel/sparse/dist/).
117 - clang, version 3.4 or later
119 Also, you may find the ovs-dev script found in utilities/ovs-dev.py useful.
121 Installation Requirements
122 -------------------------
124 The machine on which Open vSwitch is to be installed must have the
127 - libc compatible with the libc used for build.
129 - libssl compatible with the libssl used for build, if OpenSSL was
132 - On Linux, the same kernel version configured as part of the build.
134 - For optional support of ingress policing on Linux, the "tc" program
135 from iproute2 (part of all major distributions and available at
136 http://www.linux-foundation.org/en/Net:Iproute2).
138 On Linux you should ensure that /dev/urandom exists. To support TAP
139 devices, you must also ensure that /dev/net/tun exists.
141 To run the ovsdbmonitor tool, the machine must also have the following
144 - Python 2.x, for x >= 4.
146 - Python Twisted Conch.
152 - Python Zope interface module.
154 (On Debian "lenny" the above can be installed with "apt-get install
155 python-json python-qt4 python-zopeinterface python-twisted-conch".)
157 Building and Installing Open vSwitch for Linux, FreeBSD or NetBSD
158 =================================================================
160 Once you have installed all the prerequisites listed above in the Base
161 Prerequisites section, follow the procedure below to build.
163 1. If you pulled the sources directly from an Open vSwitch Git tree,
164 run boot.sh in the top source directory:
168 2. In the top source directory, configure the package by running the
169 configure script. You can usually invoke configure without any
174 By default all files are installed under /usr/local. If you want
175 to install into, e.g., /usr and /var instead of /usr/local and
176 /usr/local/var, add options as shown here:
178 % ./configure --prefix=/usr --localstatedir=/var
180 To use a specific C compiler for compiling Open vSwitch user
181 programs, also specify it on the configure command line, like so:
183 % ./configure CC=gcc-4.2
185 To use 'clang' compiler:
187 % ./configure CC=clang
189 To build the Linux kernel module, so that you can run the
190 kernel-based switch, pass the location of the kernel build
191 directory on --with-linux. For example, to build for a running
194 % ./configure --with-linux=/lib/modules/`uname -r`/build
196 If you wish to build the kernel module for an architecture other
197 than the architecture of the machine used for the build, you may
198 specify the kernel architecture string using the KARCH variable
199 when invoking the configure script. For example, to build for MIPS
202 % ./configure --with-linux=/path/to/linux KARCH=mips
204 If you plan to do much Open vSwitch development, you might want to
205 add --enable-Werror, which adds the -Werror option to the compiler
206 command line, turning warnings into errors. That makes it
207 impossible to miss warnings generated by the build.
209 The configure script accepts a number of other options and honors
210 additional environment variables. For a full list, invoke
211 configure with the --help option.
213 3. Run GNU make in the top source directory, e.g.:
217 or if GNU make is installed as "gmake":
221 For improved warnings if you installed "sparse" (see
222 "Prerequisites"), add C=1 to the command line.
224 4. Consider running the testsuite. Refer to "Running the Testsuite"
225 below, for instructions.
227 5. Become root by running "su" or another program.
229 6. Run "make install" to install the executables and manpages into the
230 running system, by default under /usr/local.
232 7. If you built kernel modules, you may install and load them, e.g.:
234 % make modules_install
235 % /sbin/modprobe openvswitch
237 To verify that the modules have been loaded, run "/sbin/lsmod" and
238 check that openvswitch is listed.
240 If the "modprobe" operation fails, look at the last few kernel log
241 messages (e.g. with "dmesg | tail"):
243 - The message "openvswitch: exports duplicate symbol
244 br_should_route_hook (owned by bridge)" means that the bridge
245 module is loaded. Run "/sbin/rmmod bridge" to remove it.
247 If "/sbin/rmmod bridge" fails with "ERROR: Module bridge does
248 not exist in /proc/modules", then the bridge is compiled into
249 the kernel, rather than as a module. Open vSwitch does not
250 support this configuration (see "Build Requirements", above).
252 - The message "openvswitch: exports duplicate symbol
253 dp_ioctl_hook (owned by ofdatapath)" means that the ofdatapath
254 module from the OpenFlow reference implementation is loaded.
255 Run "/sbin/rmmod ofdatapath" to remove it. (You might have to
256 delete any existing datapaths beforehand, using the "dpctl"
257 program included with the OpenFlow reference implementation.
258 "ovs-dpctl" will not work.)
260 - Otherwise, the most likely problem is that Open vSwitch was
261 built for a kernel different from the one into which you are
262 trying to load it. Run "modinfo" on openvswitch.ko and on
263 a module built for the running kernel, e.g.:
265 % /sbin/modinfo openvswitch.ko
266 % /sbin/modinfo /lib/modules/`uname -r`/kernel/net/bridge/bridge.ko
268 Compare the "vermagic" lines output by the two commands. If
269 they differ, then Open vSwitch was built for the wrong kernel.
271 - If you decide to report a bug or ask a question related to
272 module loading, please include the output from the "dmesg" and
273 "modinfo" commands mentioned above.
275 There is an optional module parameter to openvswitch.ko called
276 vlan_tso that enables TCP segmentation offload over VLANs on NICs
277 that support it. Many drivers do not expose support for TSO on VLANs
278 in a way that Open vSwitch can use but there is no way to detect
279 whether this is the case. If you know that your particular driver can
280 handle it (for example by testing sending large TCP packets over VLANs)
281 then passing in a value of 1 may improve performance. Modules built for
282 Linux kernels 2.6.37 and later, as well as specially patched versions
283 of earlier kernels, do not need this and do not have this parameter. If
284 you do not understand what this means or do not know if your driver
285 will work, do not set this.
287 8. Initialize the configuration database using ovsdb-tool, e.g.:
289 % mkdir -p /usr/local/etc/openvswitch
290 % ovsdb-tool create /usr/local/etc/openvswitch/conf.db vswitchd/vswitch.ovsschema
295 Before starting ovs-vswitchd itself, you need to start its
296 configuration database, ovsdb-server. Each machine on which Open
297 vSwitch is installed should run its own copy of ovsdb-server.
298 Configure it to use the database you created during step 7 of
299 installation, above, to listen on a Unix domain socket, to connect to
300 any managers specified in the database itself, and to use the SSL
301 configuration in the database:
303 % ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock \
304 --remote=db:Open_vSwitch,Open_vSwitch,manager_options \
305 --private-key=db:Open_vSwitch,SSL,private_key \
306 --certificate=db:Open_vSwitch,SSL,certificate \
307 --bootstrap-ca-cert=db:Open_vSwitch,SSL,ca_cert \
310 (If you built Open vSwitch without SSL support, then omit
311 --private-key, --certificate, and --bootstrap-ca-cert.)
313 Then initialize the database using ovs-vsctl. This is only
314 necessary the first time after you create the database with
315 ovsdb-tool (but running it at any time is harmless):
317 % ovs-vsctl --no-wait init
319 Then start the main Open vSwitch daemon, telling it to connect to the
320 same Unix domain socket:
322 % ovs-vswitchd --pidfile --detach
324 Now you may use ovs-vsctl to set up bridges and other Open vSwitch
325 features. For example, to create a bridge named br0 and add ports
326 eth0 and vif1.0 to it:
328 % ovs-vsctl add-br br0
329 % ovs-vsctl add-port br0 eth0
330 % ovs-vsctl add-port br0 vif1.0
332 Please refer to ovs-vsctl(8) for more details.
337 When you upgrade Open vSwitch from one version to another, you should
338 also upgrade the database schema:
340 1. Stop the Open vSwitch daemons, e.g.:
342 % kill `cd /usr/local/var/run/openvswitch && cat ovsdb-server.pid ovs-vswitchd.pid`
344 2. Install the new Open vSwitch release.
346 3. Upgrade the database, in one of the following two ways:
348 - If there is no important data in your database, then you may
349 delete the database file and recreate it with ovsdb-tool,
350 following the instructions under "Building and Installing Open
351 vSwitch for Linux, FreeBSD or NetBSD".
353 - If you want to preserve the contents of your database, back it
354 up first, then use "ovsdb-tool convert" to upgrade it, e.g.:
356 % ovsdb-tool convert /usr/local/etc/openvswitch/conf.db vswitchd/vswitch.ovsschema
358 4. Start the Open vSwitch daemons as described under "Building and
359 Installing Open vSwitch for Linux, FreeBSD or NetBSD" above.
363 Upgrading Open vSwitch from one version to the next version with minimum
364 disruption of traffic going through the system that is using that Open vSwitch
365 needs some considerations:
367 1. If the upgrade only involves upgrading the userspace utilities and daemons
368 of Open vSwitch, make sure that the new userspace version is compatible with
369 the previously loaded kernel module.
371 2. An upgrade of userspace daemons means that they have to be restarted.
372 Restarting the daemons means that the Openflow flows in the ovs-vswitchd daemon
373 will be lost. One way to restore the flows is to let the controller
374 re-populate it. Another way is to save the previous flows using a utility
375 like ovs-ofctl and then re-add them after the restart. Restoring the old flows
376 is accurate only if the new Open vSwitch interfaces retain the old 'ofport'
379 3. When the new userspace daemons get restarted, they automatically flush
380 the old flows setup in the kernel. This can be expensive if there are hundreds
381 of new flows that are entering the kernel but userspace daemons are busy
382 setting up new userspace flows from either the controller or an utility like
383 ovs-ofctl. Open vSwitch database provides an option to solve this problem
384 through the other_config:flow-restore-wait column of the Open_vSwitch table.
385 Refer to the ovs-vswitchd.conf.db(5) manpage for details.
387 4. If the upgrade also involves upgrading the kernel module, the old kernel
388 module needs to be unloaded and the new kernel module should be loaded. This
389 means that the kernel network devices belonging to Open vSwitch is recreated
390 and the kernel flows are lost. The downtime of the traffic can be reduced
391 if the userspace daemons are restarted immediately and the userspace flows
392 are restored as soon as possible.
394 The ovs-ctl utility's "restart" function only restarts the userspace daemons,
395 makes sure that the 'ofport' values remain consistent across restarts, restores
396 userspace flows using the ovs-ofctl utility and also uses the
397 other_config:flow-restore-wait column to keep the traffic downtime to the
398 minimum. The ovs-ctl utility's "force-reload-kmod" function does all of the
399 above, but also replaces the old kernel module with the new one. Open vSwitch
400 startup scripts for Debian, XenServer and RHEL use ovs-ctl's functions and it
401 is recommended that these functions be used for other software platforms too.
403 Running the Testsuite
404 =====================
406 Open vSwitch includes a testsuite. Before you submit patches
407 upstream, we advise that you run the tests and ensure that they pass.
408 If you add new features to Open vSwitch, then adding tests for those
409 features will ensure your features don't break as developers modify
410 other areas of Open vSwitch.
412 You must configure and build Open vSwitch (steps 1 through 3 in
413 "Building and Installing Open vSwitch for Linux, FreeBSD or NetBSD" above)
414 before you run the testsuite. You do not need to install Open vSwitch
415 or to build or load the kernel module to run the testsuite. You do
416 not need supervisor privilege to run the testsuite.
418 To run all the unit tests in Open vSwitch, one at a time:
420 This takes under 5 minutes on a modern desktop system.
422 To run all the unit tests in Open vSwitch, up to 8 in parallel:
423 make check TESTSUITEFLAGS=-j8
424 This takes under a minute on a modern 4-core desktop system.
426 To see a list of all the available tests, run:
427 make check TESTSUITEFLAGS=--list
429 To run only a subset of tests, e.g. test 123 and tests 477 through 484:
430 make check TESTSUITEFLAGS='123 477-484'
431 (Tests do not have inter-dependencies, so you may run any subset.)
433 To run tests matching a keyword, e.g. "ovsdb":
434 make check TESTSUITEFLAGS='-k ovsdb'
436 To see a complete list of test options:
437 make check TESTSUITEFLAGS=--help
439 The results of a testing run are reported in tests/testsuite.log.
440 Please report test failures as bugs and include the testsuite.log in
443 If you have "valgrind" installed, then you can also run the testsuite
444 under valgrind by using "make check-valgrind" in place of "make
445 check". All the same options are available via TESTSUITEFLAGS. When
446 you do this, the "valgrind" results for test <N> are reported in files
447 named tests/testsuite.dir/<N>/valgrind.*. You may find that the
448 valgrind results are easier to interpret if you put "-q" in
449 ~/.valgrindrc, since that reduces the amount of output.
451 Sometimes a few tests may fail on some runs but not others. This is
452 usually a bug in the testsuite, not a bug in Open vSwitch itself. If
453 you find that a test fails intermittently, please report it, since the
454 developers may not have noticed.
459 Please report problems to bugs@openvswitch.org.