******* Solved ************** I hope someone can give me concrete advice for how to handle my issue. I am working with KVM on a Debian 12 system. The install was easy, in fact cookie cutter using apt-get. I was able to easily convert my long time Vbox vdi files over to qcow2, which makes keeping my customized VM's nice and easy. However when I go to install the saved qcow2 images to build machines for KVM--- > Virt-Manager always states that the default network is inactive. I try to manually start the default network but I get the errors pasted below. Virtualbox was running fine on this machine and showed no issues with the NAT adapter being good to go, so there is a network open at boot. Thinking that just maybe VirtualBox might interfere with KVM I removed and purged Vbox 7.0 and dependencies from the host. I have forensic level backups so I can restore everything in 90 minutes therefore feel free to get "drastic" if something comes to mind. edit: I also tried to build a KVM machine from an ISO to remove the chance that my file conversions have anything to do with this. They don't. Virt-Manager simply calls the default network inactive and the terminal also shows the default network present but inactive. Hmmmmmmm Paste of errors: Could not start virtual network 'default': internal error: Failed to apply firewall rules /usr/sbin/iptables -w --table filter --list-rules: # Warning: iptables-legacy tables present, use iptables-legacy to see them iptables v1.8.9 (nf_tables): table `filter' is incompatible, use 'nft' tool. Traceback (most recent call last): File "/usr/share/virt-manager/virtManager/device/netlist.py", line 208, in _check_network_is_running netobj.start() File "/usr/share/virt-manager/virtManager/object/libvirtobject.py", line 57, in newfn ret = fn(self, *args, **kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^ File "/usr/share/virt-manager/virtManager/object/network.py", line 69, in start self._backend.create() File "/usr/lib/python3/dist-packages/libvirt.py", line 3547, in create raise libvirtError('virNetworkCreate() failed') libvirt.libvirtError: internal error: Failed to apply firewall rules /usr/sbin/iptables -w --table filter --list-rules: # Warning: iptables-legacy tables present, use iptables-legacy to see them iptables v1.8.9 (nf_tables): table `filter' is incompatible, use 'nft' tool.
Got it! Manually started "virsh" using command in a terminal. Had to lower/drop part of my nft firewall config during boot. I will go back tomorrow and find out which line was blocking the default network. I always have tun0 brought up for my VPN connection during boot. xxx@IPhone:~$ sudo virsh net-autostart default Network default marked as autostarted
