On Sat, 25 Oct 2025 13:17:00 -0600 Charles Curley <[email protected]> wrote:
> What am I missing? From what folks have said here and elsewhere, apparently using a virtual network with wifi is problematic. I began to wonder if that was my problem. So I ran "install virt-manager" on a desktop with Ethernet only. That produced a default network. Starting that network produced the virtual interface virbr0 that the default network wanted. The libvirt documentation on virtual networking is silent on the use of wifi interfaces. https://wiki.libvirt.org/VirtualNetworking.html The wiki does mention the issue for bridged networks, not for NATted networks (the default network is NATted). https://wiki.libvirt.org/Networking.html#host-configuration-bridged Given the ubiquity of laptops and wifi, I wonder about the wisdom of such a restriction. As near as I can tell the problem with using wifi isn't wifi per se. Apparently some wifi routers track MAC addresses. Your computer gets on the network using its MAC address. Your virtual machines have different MAC addresses. Linux's virtual networking is transparent, meaning it does not play with the virtual machines' MAC addresses. So the wifi router sees this new MAC address from the VM, and rejects it. Apparently my wifi access points do not care about this, as I have run VMs on laptops on my home network for years without issue. And there are solutions out there based on ebtables. I am considering filing a bug. I believe the libvirt folks should solve this problem, not Debian packagers. -- Does anybody read signatures any more? https://charlescurley.com https://charlescurley.com/blog/
