OVS Installation on CentOS 6 or 7

1. yum update -y
2. yum install gcc make python-devel openssl-devel kernel-devel graphviz kernel-debug-devel autoconf automake rpm-build redhat-rpm-config libtool checkpolicy selinux-policy-devel python-six
3. We can find OpenvSwitch in RDO repo (RDO is a community of people using and deploying OpenStack on CentOS, Fedora and RHEL):
1. wget https://rdoproject.org/repos/rdo-release.rpm 
2. rpm -i rdo-release.rpm
4. yum install openvswitch
5. Enable OVS daemon on startup and start it:
1. On CentOS 6
1. chkconfig openvswitch on
2. service openvswitch start
2. On CentOS 7:
1. systemctl -l start openvswitch.service
2. systemctl -l enable openvswitch.service
6.  In order to avoid possible conflicts in networking:
1. yum remove NetworkManager
7. To verify your OVS installation:
1. ovs-vsctl -V
   ovs-vsctl (Open vSwitch) 2.5.0
   Compiled Mar 18 2016 15:00:11
   DB Schema 7.12.1
2.  ovs-vsctl show
   1c490f2d-68c0-4dd0-a0de-cdcaa944711a
   ovs_version: "2.5.0"