How do I set Raspbian to use the wifi even though the ethernet cable is plugged in?

Question

Currently my /etc/network/interfaces looks like this:

auto lo
iface lo inet loopback

allow-hotplug wlan0
auto wlan0
iface wlan0 inet dhcp
    wpa-ssid %WIFINAME%
    wpa-psk %WIFIPASSWORD%

allow-hotplug eth0
auto eth0
iface eth0 inet static
    address 192.168.xx.xxx
    netmask 255.255.255.0
    gateway 0.0.0.0

Obviously, "wpa-ssid %WIFINAME%", "wpa-psk %WIFIPASSWORD%", and "address 192.168.xx.xxx" are properly filled out, my wifi works without the ethernet cable plugged in, but when the cable is in, the wifi no longer works and I can't get a connection.

My goal is to have a static IP address on eth0 to run synergy on between my laptop and the pi, and then have all other traffic go through wifi using the Edimax dongle by default, how would I go about doing that?

Answer 1

This isn't a proper answer but may be enough for you to find a solution.

I use the following snippet to route packets through wlan0 when eth0 is also plugged in.

sudo route del 192.168.1.254
sudo route del default
sudo route add -net 192.168.1.254 netmask 255.255.255.255 dev wlan0
sudo route add default gw 192.168.1.254
sudo sysctl -w net.ipv4.ip_forward=1

where 192.168.1.254 is the IP address of my wireless router.