Routing Fundamentals and Diagnostics Questions

Core routing concepts and practical diagnostics for both control plane and data plane issues. Coverage includes static versus dynamic routing, prefix notation and classless interdomain routing, routing tables, default routes, longest prefix selection, route summarization and redistribution, and policy based routing. Candidates should understand convergence and failover behavior and be familiar with routing protocols such as Border Gateway Protocol for interdomain routing and Open Shortest Path First for intradomain routing, including path selection attributes and techniques such as local preference, autonomous system path preference, multi exit discriminator, and equal cost multipath. Diagnostic topics include traceroute analysis, route advertisement inspection, route table validation, and troubleshooting common faults like route leaks, blackholes, incorrect next hops, and aggregation errors.