OVN and Red Hat Virtualization: Installing OVN

Hi folks, in the last article I provided an overview and introduction to OVN. This time around, I’ll provide a walkthrough on how to actually install it in your RHV environment. My colleague Tony created an Ansible playbook to automate the installation, and I’ll share the link to that at the end. Let’s get started.

Necessary Channels and Subscriptions

One of the first thing that Tony covers in the demo is that he used the standard channels for both RHV-M (engine) and Hosts (hypervisors) – nothing special is needed from a subscription standpoint as all of the packages are now included in RHV 4.1. Using the `ovs-vsctl show` command, we see that even though the openvswitch package is pulled in as part of the host install, nothing is configured by default.

Automate the Installation with Ansible

NOTE: RHV 4.2 (beta released as of Jan 4, 2018) and RHV-M 4.2 automatically uses Ansible to configure hosts for OVN (when necessary), thus the following steps will not be necessary.

Next, we see Tony’s Ansible playbook. It covers 2 plays, one for the engine (RHV-M) and one for the hosts. Not only does it install the packages, but it configures firewalld. Specifically, the playbook does the following:

On the Engine:

It installs “ovirt-provider-ovn” package then it starts/restarts multiple services, north and southbound connections are set.

On the Hosts:

It installs the “ovirt-provider-ovn-driver” package. The `vdsm-tool` command is run to connect everything in RHV to OVN.

I should point out that there is no requirement for the OVN controller to be on the same host or VM as RHV-M. It can be on a separate host if there is a need to conserve resources on the RHV-M host or if a separate group, like the networking or security folks, require a separate controller host for SDN.

Once the playbook is run, the OVN package install is verified, as is basic configuration. Although there is nothing configured in northbound, the tunnels are created in southbound – 1 for each host (chassis).

Let’s take a look at the demo (best viewed in full screen):

Wrapping Up

If you want to pull down Tony’s Ansible Playbook, you can find that at:


In the next (and final) article, I’ll show you how to deploy VMs in RHV that utilize the OVN integration.

Hope this helps,

Captain KVM

Agree? Disagree? Something to add to the conversation?