Troubleshooting Data Plane With Rule Verification in Software-Defined Networks

Abstract

Data plane network issues, caused by software bugs or hardware failures inside network devices, usually manifest themselves as failed rules, which can be verified by the comparison between actual and desired network behavior. Previous efforts implement this leveraging end-to-end active probing, which falls short on timely locating the exact failure points and identifying responsible rules. With the help of the out-band channel in software-defined network (SDN), per hop active probing can be employed to enable per device or even per rule network behavior comparison to verify the effectiveness of all the rules. Therefore, we present SERVE, an SDN-enabled rule verification framework that automatically identifies data plane network issues with periodic per rule network behavior comparison. By modeling network devices as stateful multi-rooted trees with respect to pipeline processing, a small number of probes can be generated from a per device perspective in a timely manner. We evaluate the performance of SERVE's probe generation and validate SERVE's effectiveness on a small deployment with typical use cases.