OPENVSWITCH LTS IN CENTOS 6

As some visitors have asked me about installing Open vSwitch on CentOS 6, I’m writing the following post after my first about it almos three years ago. If you find a better way, please let me know so I update the post and remove useless info from the Internet 😉

I’ve found this repository by Alexander Evseev so you may try to use the openvswitch packages (you even have the kmod package) found there. Have a look: http://download.opensuse.org/repositories/home:/aevseev/CentOS6/x86_64/

In any case… I’ll show you what you can do to generate your own RPM packages the old way (no python api supported as it requires Python 2.7 while CentOS 6 uses Python 2.6):

Current LTS version: 2.5.0
Tested on: CentOS 6.8

Let’s start installing some packages:

yum -y install wget openssl-devel gcc make python-devel openssl-devel kernel-devel graphviz kernel-debug-devel autoconf automake rpm-build redhat-rpm-config libtool python-twisted-core python-zope-interface PyQt4 desktop-file-utils libcap-ng-devel groff checkpolicy selinux-policy-devel

Let’s add a new user and switch to that user:

adduser ovs; su - ovs

Let’s prepare the build environment and download the source code:

mkdir -p ~/rpmbuild/SOURCES
wget http://openvswitch.org/releases/openvswitch-2.5.0.tar.gz
cp openvswitch-2.5.0.tar.gz ~/rpmbuild/SOURCES/
tar xfz openvswitch-2.5.0.tar.gz

Now go to the openvswitch directory

cd openvswitch-2.5.0

Let’s modify some lines in the old rhel6 spec file provided by Nicira (copy and paste):

sed -i "s/Requires: logrotate, python >= 2.7/Requires: logrotate/" rhel/openvswitch.spec
sed -i "/$RPM_BUILD_ROOT\/usr\/bin\/ovs-test/d" rhel/openvswitch.spec
sed -i "/$RPM_BUILD_ROOT\/usr\/bin\/ovs-l3ping/d" rhel/openvswitch.spec
sed -i "/\/usr\/bin\/ovs-parse-backtrace/d" rhel/openvswitch.spec
sed -i "/\/usr\/bin\/ovs-pcap/d" rhel/openvswitch.spec
sed -i "/\/usr\/bin\/ovs-tcpundump/d" rhel/openvswitch.spec
sed -i "/\/usr\/bin\/ovs-vlan-test/d" rhel/openvswitch.spec
sed -i "/\/usr\/share\/man\/man8\/ovs-bugtool.8.gz/d" rhel/openvswitch.spec
sed -i "/\/usr\/share\/openvswitch\/bugtool-plugins/d" rhel/openvswitch.spec
sed -i "/\/usr\/share\/openvswitch\/scripts\/ovs-bugtool-*/d" rhel/openvswitch.spec
sed -i "/\/usr\/share\/openvswitch\/python/d" rhel/openvswitch.spec
sed -i "/\/usr\/share\/openvswitch\/scripts\/ovs-bugtool-*/d" rhel/openvswitch.spec
sed -i "/\/usr\/bin\/ovs-dpctl-top/d" rhel/openvswitch.spec
sed -i "/\/usr\/sbin\/ovs-bugtool/d" rhel/openvswitch.spec
echo "/usr/bin/ovs-testcontroller" >> rhel/openvswitch.spec

Finally let’s build the RPM packages… and have a cup of coffee as tests are being run! At least you can tell if it works… 😛

rpmbuild -bb rhel/openvswitch.spec

Once the build is finished, type exit.

exit

CentOS 6 already provides an openvswitch kernel module, so we’ve only compiled the binary tools.

[root@localhost ~]# modinfo openvswitch
filename: /lib/modules/2.6.32-642.3.1.el6.x86_64/kernel/net/openvswitch/openvswitch.ko
license: GPL
description: Open vSwitch switching datapath
srcversion: 00938868C288DBF055E30F3
depends: libcrc32c,vxlan
vermagic: 2.6.32-642.3.1.el6.x86_64 SMP mod_unload modversions

As root, we’ll install the RPM package.

 yum localinstall /home/ovs/rpmbuild/RPMS/x86_64/openvswitch-2.5.0-1.x86_64.rpm -y

Finally, start the openvswitch service and check that it’s running

service openvswitch start
...output...
/etc/openvswitch/conf.db does not exist ... (warning).
Creating empty database /etc/openvswitch/conf.db [ OK ]
Starting ovsdb-server [ OK ]
Configuring Open vSwitch system IDs [ OK ]
Inserting openvswitch module [ OK ]
Starting ovs-vswitchd [ OK ]
Enabling remote OVSDB managers [ OK ]

service openvswitch status
...output...
ovsdb-server is running with pid 3404
ovs-vswitchd is running with pid 3416

If you want the openvswitch service to start at boot time:

chkconfig openvswitch on

Let’s check that the command-line tools are ready:

ovs-vsctl -V
...output...
ovs-vsctl (Open vSwitch) 2.5.0
Compiled Aug 31 2016 19:54:41
DB Schema 7.12.1

Done. I can’t be sure if it will work for you as I haven’t been using Open vSwitch with CentOS 6 for a long time… so any feedback is welcomed!

Cheers!