Building your own CGN boxes with Linux

Maximilian Wilhelm

Playlists: 'denog12' videos starting here / audio

This talk will show how to build your own simple, cheap and scalable CGN solutions with stateful-failover with commodity servers with a decent NIC running Linux, nftables, and bird.

We were in need to introduce NAT into the network and a commercial solution would have required a 6 figure invest, so we build it ourselves for <10% of that cost.

Two Dell servers with a recent CPU, two Mellanox NICs and nftables as well as bird do the trick and make for a simple, cheap and scalable CGN box, supporting ECMP, simple draining and orchestration by your usual Linux tool chain as well as stateful-failover.