I'm working on a project whilst in lockdown in England, and I am hoping someone can offer some advice?
I have a machine with 5 physical eth interfaces on Linux Mint, 20.04. All eth interfaces communicate as expected through firewalld and the world is 'almost' roses. Eth4 is my gateway to the outside world, and eth0-3 are internals. All fine, can ping and talk to each other. Eth0-3 are bridges on a bridge port br0.
What I am aiming to do is add 1 or 2 virtual machines, with virtualbox, on to this host. Then use kernel networking with a tun or tap interface to bridge the virtual machines into the br0 interface.
I have tried all sorts of solutions over the past week, with my most successful being the vm machine getting an IP from the hosts ISC-DHCP-SERVER, but then no IP traffic going over that connection.
Can anyone please advise whether it is possible to create a virtualbox machine, and attach it to a tap or tun interface on the host, and build the tap/tun interface into the bridged br interface?
If so, a few clues would be great! I'm using this as a learning experience about the linux networking stack whilst in lockdown, but have hit a brick wall, so any help would be appreciated!
My kind regards and Thanks in advance,
Ian B