My proxmox “cluster” is a bunch of old laptops with a single consumer grade NIC in each. I wanted to isolate the VM network from my main home network (have it on a different range) while still allowing all the VM’s to transparently talk to each other regardless of which physical host they happen to be on.

Could I have achieved this with normal vlans? I wanted an overlay network on the VM side but they still need to use my main home network to get internet and I only have a single physical interface.

The OPNsense VM routes between the two networks (the virtual vxlan within Proxmox + my physical home network)