There are typically two ways to create a bridged network setup: Create a bridge out of your main network interface, and assign it the IP address you normally would have on your main interface, so that you can use it for the bridge and for the containers as well. Create a different bridge that is independent of your main interface but that gets traffic forwarded to it (and from it). The remainder of this introduction covers only part 2.
Sorgente: LXC/SimpleBridge – Debian Wiki