Hi,

On 09.11.22 16:35, Pascal wrote:

          \                     /
  +--------\-------+   +-------/-------+
  |free GW         |   |corporate GW   |
  |192.168.144.254 |   |10.10.10.254/24|
  +--------|-------+   +-------|-------+
           \                  /

+---------------|-----------------|------+ |HOST |wlan0 | |eth0 | | |192.168.144.1/24| |10.10.10.1/24| | +----------------+ +-------------| | | | +-----------------+ | | |tap0 | | | |192.168.11.254/24| | | +--------|--------+ | | | | | +-------------|--------+ | | |VM |eth0 | | | | |192.168.11.1/24 | | | | +-----------------| | | +----------------------+ | +----------------------------------------+

you're going to need source policy routing.

I.e. create a new routing table with the default route going through your free GW:

ip route add default via 192.168.144.254 table 10

To check if it's in place:

ip route show table 10

And then to direct your VM traffic through that, you need a routing rule:

ip rule add from 192.168.11.0/24 lookup 10 priority 10

To check if it's in place:

ip rule show

The main routing table usually has a priority of 32766 and to place overrides you need to insert rules with a lower priority number, they are processed from low to high.

For a permanent setting, you can add your additional routing tables to /etc/iproute2/rt_tables and even give them a name there. The routes and routing rules themselves need to be inserted separately, I don't know from the top of my head if systemd-networkd can do that for you, otherwise you're going to need some sort of Oneshot post-boot service that sets it up.

For more details you might want to consult the ip-rule and ip-route man pages.

Cheers