Re: [libvirt-users] Network hooks for ethernet interfaces

On Wed, Apr 10, 2019 at 1:44 PM Laine Stump <laine(a)redhat.com&gt; wrote: > > On 4/9/19 11:35 AM, Ruben Kerkhof wrote: > > On Tue, Apr 9, 2019 at 5:10 PM Michal Privoznik <mprivozn(a)redhat.com&gt; wrote: > >> > >> On 4/9/19 4:38 PM, Ruben Kerkhof wrote: > >>> Hi all, > >>> > >>> I have a hook script, /etc/libvirt/hooks/network, that doesn't seem to > >>> be called when I attach an interface with type 'ethernet' with this > >>> xml snippet: > >>> > >>> <interface type='ethernet'> > >>> <model type="virtio"/> > >>> <source> > >>> <ip address="10.100.0.1" prefix="24" peer="10.100.0.10"/> > >>> </source> > >>> </interface> > >>> > >>> https://www.libvirt.org/hooks.html#intro says > >>> "A network is started or stopped or an interface is plugged/unplugged > >>> to/from the network (since 1.2.2)". > >>> > >>> While I don't have a network defined in xml, I'd expect this to work > >>> just as well for 'ethernet' type interfaces. Am I wrong? > >> > >> > >> Hotplugging an 'ethernet' type of interface doesn't really relate to any > >> libvirt network. Hence libvirt doesn't call 'network' hook script. If > >> you'd continue reading you'll see what is the 'network' hook fed with > >> (on stdin): info on domain in question AND network where the event > >> ocurred. But there is no network, is it? > > > > No not in the libvirt sense there isn't, you're right. > >> > >> But maybe you can work around this by waiting for > >> DEVICE_ADDED/DEVICE_REMOVED events? What is it that you're trying to solve? > > > > I'd like to enable proxy_arp on the interface among other things. > > I can easily do this from the same script that adds the interface > > though, so I have a workaround, but a hook that triggers on all > > interface events felt cleaner. > > Also keep in mind that the hook scripts aren't an officially supported > part of the API, and are thus liable to change without warning. As an > example, danpb has proposed changing the network hook: > > https://www.redhat.com/archives/libvir-list/2019-March/msg01280.html > > Once this goes in, any network hook script that uses the plugged and > unplugged hooks will no longer work; you would instead need to use the > port-created and port-deleted hooks. That's good to know, thank you Laine. In that case perhaps adding this functionality to libvirt itself would make more sense? Some background, I'm implementing https://vincent.bernat.ch/en/blog/2018-l3-routing-hypervisor, so announcing /32 host routes to our vms with BGP. Our existing vms use /24 network addressing, and to keep that working, I need to set proxy_arp on the interface.