Cloudflare Tunnel is a tunneling service provided by Cloudflare. With Cloudflare Tunnel you can connect the origin to Cloudflare and provide service without exposing any ports on the server or cluster, therefore minimizing the attack surface.
Cloudflare Tunnel was formerly known as Argo Tunnel. Later Cloudflare Tunnel became part of the Cloudflare Zero Trust and became available to all users for free in 2021.
Cloudflare Tunnel had several iterations in the past two years, many tutorials on the interne have become outdated. The latest Cloudflare Tunnel needs no configuration on the client (cloudflared) side besides token. All sites (services) can be configured on the Cloudflare web console. If a tutorial ask you to configure the site on Cloudflared through yaml, the tutorial is likely outdated.
This post will use httpbin as an example to illustrate how to deploy Cloudflared on Kubernetes and serve other services deployed on the cluster.