Re: [libvirt] [RFC Incomplete Patch] Libvirt + Openvswitch

On 01/31/2012 06:57 AM, Daniel P. Berrange wrote: > On Fri, Jan 27, 2012 at 02:58:58AM -0800, Dan Wendlandt wrote: > >> Hello all, >> >> I know of many people who want to spin up VMs using libvirt + kvm/qemu >> and >> attach those VMs to an openvswitch bridge (see: >> http://www.openvswitch.org). >> However, the only way I know of to get this working is a kludge that >> uses >> to tap devices along with<interface type="ethernet"> while running >> ovs-vsctl outside of libvirt. Even worse, doing this on RHEL/Fedora >> seems >> to require privilege tweaks (e.g., running qemu as root, not dropping >> capabilities), which may not be acceptable for production deployments >> (see: >> http://fedoraproject.org/wiki/**How_to_debug_Virtualization_** >> problems#Errors_using_.**3Cinterface_type.3D.**27ethernet.27.2F.3E<htt... >> ). >> >> So I would like to start taking steps toward better libvirt/openvswitch >> integration. My initial step has the fairly limit goal of enabling >> kvm/qemu VM NICs to attach to an openvswitch bridge in much the same way >> VM >> NIC can already attached to the linux bridge. For example, specifying: >> >> <interface type="openvswitch"> >> <source bridge="br0"/> >> <mac address="ca:fe:de;ad:be:ef"/> >> </interface> >> > IMHO we should not be introducing a new "type" for OpenVSwitch. Contrary > to common understanding, type='bridge' is not referring explicitly to > Linux software bridging. Rather it refers to the concept of bridging the > guest to the LAN at the network level, of which Linux software briding > is one possible impl. OpenVSwitch is another possible impl. Other > hypervisors > have different impls too of course. > > If OpenVSwitch is available in the kernel, is there really any reason > to *not* use it ? ie, could we just have > > <interface type="bridge"> > <source bridge="br0"/> > <mac address="ca:fe:de;ad:be:ef"/> > </interface> > > and if we see that 'br0' is using OpenVSwitch, then libvirt can know > to just do the right thing. > Of course! <facepalm/> If the code can tell that br0 is an openvswitch bridge rather than a linux host bridge, we don't even have to add type='openvswitch' to the <source> element! I definitely like this the best, too. That way every application that uses > libvirt today will automatically be able to take advantage of the > benefits OpenVSwitch brings without further work > Except that an interfaceid is needed (or is that optional?) -- libvir-list mailing list libvir-list(a)redhat.com https://www.redhat.com/**mailman/listinfo/libvir-list<https://www.redh...