This document describes how to build and install Open vSwitch on a Red Hat Enterprise Linux (RHEL) host. If you want to install Open vSwitch on a generic Linux host, refer to :doc:`general` instead.
We have tested these instructions with RHEL 5.6 and RHEL 6.0.
For RHEL 7.x (or derivatives, such as CentOS 7.x), you should follow the instructions in the :doc:`fedora`. The Fedora spec files are used for RHEL 7.x.
You may build from an Open vSwitch distribution tarball or from an Open vSwitch Git tree.
The default RPM build directory, _topdir, has five directories in the
top-level.
- BUILD/
- where the software is unpacked and built
- RPMS/
- where the newly created binary package files are written
- SOURCES/
- contains the original sources, patches, and icon files
- SPECS/
- contains the spec files for each package to be built
- SRPMS/
- where the newly created source package files are written
Before you begin, note the RPM sources directory on your version of RHEL. The
command rpmbuild --showrc will show the configuration for each of those
directories. Alternatively, the command rpm --eval '%{_topdir}' shows the
current configuration for the top level directory and the command rpm --eval
'%{_sourcedir}' does the same for the sources directory. On RHEL 5, the
default RPM _topdir is /usr/src/redhat and the default RPM sources
directory is /usr/src/redhat/SOURCES. On RHEL 6, the default _topdir is
$HOME/rpmbuild and the default RPM sources directory is
$HOME/rpmbuild/SOURCES.
You will need to install all required packages to build the RPMs. The command below will install RPM tools and generic build dependencies:
$ yum install @'Development Tools' rpm-build yum-utils
Then it is necessary to install Open vSwitch specific build dependencies. The dependencies are listed in the SPEC file, but first it is necessary to replace the VERSION tag to be a valid SPEC.
The command below will create a temporary SPEC file:
$ sed -e 's/@VERSION@/0.0.1/' rhel/openvswitch.spec.in > /tmp/ovs.spec
And to install specific dependencies, use yum-builddep tool:
$ yum-builddep /tmp/ovs.spec
Once that is completed, remove the file /tmp/ovs.spec.
If python3-sphinx package is not available in your version of RHEL, you can install it via pip with 'pip install sphinx'.
Open vSwitch requires python 3.4 or newer which is not available in older distributions. In the case of RHEL 6.x and its derivatives, one option is to install python34 from EPEL.
If you are building from a distribution tarball, skip to :ref:`rhel-building`.
If not, you must be building from an Open vSwitch Git tree. Determine what
version of Autoconf is installed (e.g. run autoconf --version). If it is
not at least version 2.63, then you must upgrade or use another machine to
build the packages.
Assuming all requirements have been met, build the tarball by running:
$ ./boot.sh $ ./configure $ make dist
You must run this on a machine that has the tools listed in :ref:`general-build-reqs` as prerequisites for building from a Git tree. Afterward, proceed with the rest of the instructions using the distribution tarball.
Now you have a distribution tarball, named something like
openvswitch-x.y.z.tar.gz. Copy this file into the RPM sources directory,
e.g.:
$ cp openvswitch-x.y.z.tar.gz $HOME/rpmbuild/SOURCES
Some versions of the RHEL 6 kernel-devel package contain a broken build
symlink. If you are using such a version, you must fix the problem before
continuing.
To find out whether you are affected, run:
$ cd /lib/modules/<version> $ ls -l build/
where <version> is the version number of the RHEL 6 kernel.
Note
The trailing slash in the final command is important. Be sure to include it.
If the ls command produces a directory listing, your kernel-devel package
is OK. If it produces a No such file or directory error, your kernel-devel
package is buggy.
If your kernel-devel package is buggy, then you can fix it with:
$ cd /lib/modules/<version> $ rm build $ ln -s /usr/src/kernels/<target> build
where <target> is the name of an existing directory under
/usr/src/kernels, whose name should be similar to <version> but may
contain some extra parts. Once you have done this, verify the fix with the
same procedure you used above to check for the problem.
You should have a distribution tarball named something like openvswitch-x.y.z.tar.gz. Copy this file into the RPM sources directory:
$ cp openvswitch-x.y.z.tar.gz $HOME/rpmbuild/SOURCES
Make another copy of the distribution tarball in a temporary directory. Then
unpack the tarball and cd into its root:
$ tar xzf openvswitch-x.y.z.tar.gz $ cd openvswitch-x.y.z
To build Open vSwitch userspace, run:
$ rpmbuild -bb rhel/openvswitch.spec
This produces two RPMs: "openvswitch" and "openvswitch-debuginfo".
The above command automatically runs the Open vSwitch unit tests. To disable the unit tests, run:
$ rpmbuild -bb --without check rhel/openvswitch.spec
Note
If the build fails with configure: error: source dir
/lib/modules/2.6.32-279.el6.x86_64/build doesn't exist or similar, then
the kernel-devel package is missing or buggy.
A RHEL host has default firewall rules that prevent any Open vSwitch tunnel traffic from passing through. If a user configures Open vSwitch tunnels like Geneve, GRE, VXLAN, LISP etc., they will either have to manually add iptables firewall rules to allow the tunnel traffic or add it through a startup script Refer to the "enable-protocol" command in the ovs-ctl(8) manpage for more information.
In addition, simple integration with Red Hat network scripts has been implemented. Refer to README.RHEL.rst in the source tree or /usr/share/doc/openvswitch/README.RHEL.rst in the installed openvswitch package for details.
Report problems to [email protected].