Forward a TCP port to another IP or port using NAT with nftables

Video Description

This video covers the explanation and configuration steps to configure a port forward using nftables on Debian, Ubuntu, CentOS and RHEL. Timestamps: Theoretical explanation: https://youtu.be/bH4iibrSvFM?t=63 Debian and Ubuntu: https://youtu.be/bH4iibrSvFM?t=209 CentOS and RHEL: https://youtu.be/bH4iibrSvFM?t=496 With a port forward, you can redirect all traffic that is sent to a certain TCP port to another host. In practice, this technique can be used to test a service on a new host without adjusting anything on the client. When the test would be unsuccessful, removing the NAT-rule is all it takes to switch back. Since most major distributions switched to nftables instead of iptables, I decided to create this content. Debian has nftables since Debian 10 (Buster) and CentOS and RHEL since version 8. Ubuntu also very recently, since 20.10 (Groovy Gorilla), moved to nftables. First I'll explain the theory behind the port forward, then we'll look into getting direct access to nftables, by disabling UFW or firewalld. Next, we make sure IP forwarding is enabled and then we test and enable the port forward. Finally, I'll explain how to make the changes persistent. All info discussed and shown in the video can be found well-documented on my blog, jensd.be, as well. For this video: https://jensd.be/1086/linux/forward-a-tcp-port-to-another-ip-or-port-using-nat-with-nftables