21CTO

Aug 31, 2026 · Industry Insights

How a ‘Cisco Expert’ with Only Three Months’ Experience Blew Up a Customer’s Network

A junior network engineer, labeled the company’s ‘Cisco expert’ after just three months, installed a new switch for a client, misconfigured its spanning‑tree protocol, caused massive AS/400 data loss, and learned hard lessons about over‑promoting novices.