Lightweight tunneling (LWT) has been supported on linux kernel since almost 10 years ago. It enables virtual environments to scale up their tunneling infrastructure, especially when containers are involved and container-to-container communication is needed.

Nftables now allows to scale up with tunnel expression, combining it with the infrastructure existing ruleset and other powerful features like maps, sets and stateful objects. During this talk, we will get a good understanding of what is the lightweight tunneling, when it can be useful and how to use it together with Nftables.