Free Range Routing Monitoring and Anomaly Detection Tool

Modern dynamic routing environments often suffer from limited visibility and diagnostic capabilities at the individual router level. This is especially true for setups based on Free Range Routing (FRR), an open-source routing suite that implements routing protocols like Open Shortest Path First (OSPF) and Border Gateway Protocol (BGP). Operators are typically forced to inspect each router’s state manually via Command Line Interface (CLI), making it difficult to detect and understand anomalies such as missing or unexpected route advertisements. These issues can compromise network stability and make troubleshooting time-consuming and error-prone.

We developed FRR-MAD, a modular, open-source monitoring and anomaly detection tool tailored to OSPF in FRRouting, to address these issues. It parses and analyzes routing data, detects inconsistencies, and visualizes the router’s state through an interactive text-based user interface (TUI). FRR-MAD consists of two components: the frr-mad-analyzer, which acts as the backend, collecting and evaluating OSPF data from FRR and the frr-mad-tui, a terminal-based frontend that presents the data for monitoring and troubleshooting. Features like structured route overviews, live anomaly highlighting, filtering, and Prometheus-compatible export simplify OSPF diagnostics and make routing behavior easier to understand, even in complex environments. An additional artifact that arose from this thesis is a containerlab-based development and test environment, which allows users to quickly spin up a realistic multi-router topology and test FRR-MAD without impacting production systems.

FRR-MAD enhances the monitoring and troubleshooting of OSPF routing in FRR environments by providing live anomaly detection and intuitive visualization. Its open-source nature encourages community collaboration. We invite the FRR community to adopt, test, and contribute to the project1 . Developed in close collaboration with our project partner Open Systems, this tool is now being integrated into their production infrastructure.