This appliance provides an Open vSwitch, it's based on Alpine Linux. Open vSwitch is documented at http://docs.openvswitch.org/en/stable/.
This image is derived from the GNS3 appliance, for details see https://github.com/GNS3/gns3-registry/tree/master/docker/openvswitch
On the first run the container creates bridges br0 to br3. All eth interfaces without network configuration are connected to br0.
In subsequent starts of the VM, the config of the previous run is restored.
The IP configuration of the bridge interfaces, such as br0,
can be set using the normal /etc/network/interfaces file.
It's recommended to omit/comment any
auto br<if> lines,
otherwise you will get a (harmless) warning during startup.
The custom script
/etc/openvswitch/init.sh can be used for