BirdNest Tech Talk

Jun 30, 2026 · Operations

Building VXLAN Probes with evr: Monitoring Edge Routers Without Agents

The article explains how Baidu’s open‑source evr tool leverages VXLAN VTEP reflection to monitor Edge Virtual Routers from a single side, detailing packet construction, payload encoding, raw‑socket handling, BPF filtering, ECMP coverage, and practical configuration for reliable loss, latency, and bit‑flip detection.