https://wiki.debian.org/BridgeNetworkConnections

apt install bridge-utils

ip link show
brctl addbr br42
brctl addif br42 enp5s2
ip link set enp5s2 up
ip link set enp5s2 master br42
ip link set br42 up
ip link show

cat /etc/network/interfaces

iface eno2 inet static
        address 192.168.168.123
        broadcast 192.168.168.255
        netmask 255.255.255.0
        gateway 192.168.168.254

iface enp0s25 inet manual

auto br42
iface br42 inet dhcp
        bridge_ports enp0s25
        bridge_stp off       # disable Spanning Tree Protocol
        bridge_waitport 0    # no delay before a port becomes available
        bridge_fd 0          # no forwarding delay

cat bridged-network.xml

<network>
<name>bridged-network</name>
<forward mode="bridge" />
<bridge name="br42" />
</network>

virsh net-define bridged-network.xml
virsh net-start bridged-network
virsh net-autostart bridged-network

systemctl restart networking.service

---

virsh net-list –all
virsh net-autostart default