Building a High-Performance DDoS Mitigation Pipeline with nftables and XDP

Distributed Denial of Service (DDoS) attacks continue to evolve in both scale and complexity. For developers and infrastructure operators running public-facing services—especially game servers and APIs—basic firewall rules are no longer sufficient. This article outlines a practical approach to building a high-performance mitigation pipeline using Linux-native technologies such as nftables and XDP. The concepts presented here are based on real-world implementations used at ArzenLabs. Problem Overview Typical attack patterns observed in production environments include: High packet-rate UDP floods targeting open service ports Amplification attacks using spoofed sources Burst traffic designed to exhaust connection tracking These attacks aim to overwhelm network handling capacity rather than exploit application logic. Architecture Overview An effective mitigation pipeline should operate across multiple layers: Early packet drop (XDP / eBPF) Kernel-level filtering (nftables) Dynamic reputati