Thank you Laine and thanks Michal for the detailed explanation. To add some (missing) context from my side:
I was attempting to virtualize Raspberry Pi on qemu via libvirt, where my host machine is macOS (both qemu and libvirt installed via Homebrew) and I while trying to set up the network I stumbled upon this: $ virsh -c qemu:///system?socket=/usr/local/var/run/libvirt/libvirt-sock net-list --all error: Failed to get the number of active networks error: this function is not supported by the connection driver: virConnectNumOfNetworks This error in combination with the compatibility matrix made me think it's just not supported. What is the right way of interpreting this error/state? Does the host OS play a role in the compatibility? Are there any known limitations on macOS, or is this likely just a broken/misconfigured installation on my side? Radek Simko On Mon, Mar 29, 2021 at 10:29 AM Michal Privoznik <mpriv...@redhat.com> wrote: > On 3/27/21 1:39 PM, Radek Simko wrote: > > Hi, > > According to this support matrix > > https://libvirt.org/hvsupport.html#virNetworkDriver > > <https://libvirt.org/hvsupport.html#virNetworkDriver> > > there is no support for any APIs other than hypervisor ones for qemu. > > For example virConnectNumOfNetworks is not supported. > > > > Is there any particular reason this is not supported? Has any > > development in that area been attempted in the past? Would contributions > > adding support be welcomed? > > To extend Laine's reply: > > Libvirt has two set of drivers: statefull (where libvirt keeps the state > of resources like domains, networks, ...) and stateless (where libvirt > merely translates from/to APIs exposed by hypervisor). > > QEMU can be an example of a statefull driver, ESX or hyperv are examples > of stateless drivers. Stateless drivers also implement network APIs > (again, by translating from/to APIs exposed by the underlying hypervisor > - ESX or hypverv in this example), whereas statefull drivers use bridge > driver. Therefore, QEMU doesn't implement any network APIs. > > > This is even more visible with split daemons (where monolithic libvirtd > is broken into smaller daemons) - if virnetworkd is not running then > things like 'virsh net-list' return an error [*]. > > > Is there any particular problem you're facing? > > Michal > > > * - except not really, because these split daemons are socket activated, > so virnetworkd is stared automatically when needed. > >
