Diagnosing and Repairing Distributed Routing Configurations Using Selective Symbolic Simulation

TL;DR

S^2Sim is an automated system that uses selective symbolic simulation to diagnose and repair distributed routing configuration errors efficiently, reducing manual effort and enabling quick fixes for complex network scenarios.

Contribution

The paper introduces S^2Sim, a novel symbolic simulation-based approach for automatic diagnosis and repair of routing configuration errors in distributed networks.

Findings

Diagnoses and repairs WAN configurations within 10 seconds.

Handles complex scenarios like multiple protocol networks.

Effective for networks of size up to 1000 nodes.

Abstract

Although substantial progress has been made in automatically verifying whether distributed routing configurations conform to certain requirements, diagnosing and repairing configuration errors remains manual and time-consuming. To fill this gap, we propose S^2Sim, a novel system for automatic routing configuration diagnosis and repair. Our key insight is that by selectively simulating variants of the given configuration in a symbolic way, we can find an intent-compliant variant, whose differences between the given configuration reveal the errors in the given configuration and suggest the patches. Building on this insight, we also design techniques to support complex scenarios (e.g., multiple protocol networks) and requirements (e.g., k-link failure tolerance). We implement a prototype of S^2Sim and evaluate its performance using networks of size O(10) ~ O(1000) with synthetic real-world configurations. Results show that S^2Sim diagnoses and repairs errors for 1) all WAN configurations within 10 s and 2) all DCN configurations within 20 minutes.