What is rp_filter and what is it used for?

July 15, 2025

In the world of Linux and networking technologies, there are many subtle but critically important kernel settings. One such setting is rp_filter. This parameter, often overlooked, plays a key role in network security and correct packet routing. Let’s explore what it is, how it works, and why understanding it is essential for every system administrator.

What is rp_filter?

rp_filter stands for Reverse Path Filtering. It’s a Linux kernel mechanism that checks incoming network packets to verify whether they arrived on the interface through which a reply to the sender’s IP address would be routed.

Publishing Your Website from a Home PC: Cloudflare Tunnel Without a White IP

June 16, 2025

There’s often a need to host a website, be it a personal blog, a test project, or a small service, directly on a home computer. This is convenient, economical, and provides full control. However, many face the problem of not having a “white” (public) IP address from their internet provider, making direct external access virtually impossible. And even if they do, it’s often dynamic, requiring constant updates via DDNS.

Don’t worry! Today, we’ll dive into the world of network technologies and show you how to overcome this limitation and publish your website online using a powerful and free tool from Cloudflare – Cloudflare Tunnel (formerly known as Argo Tunnel). You won’t need a white IP, port forwarding on your router, or other complex configurations!