This article presents a simple four-step troubleshooting method to help readers quickly locate and resolve optical module failures in switches, ensuring smooth network operation. However, in actual deployment and operation and maintenance processes, optical link failures such as optical module docking failures and port Down often occur, which not only cause data transmission interruptions but may also affect business continuity. Check compatibility between the optical module and switch Most switch brands have specific compatibility requirements. An optical module is a critical component in modern optical communication systems, directly affecting transmission stability, network reliability, and operational efficiency. Therefore, understanding common optical module. However, even in well-designed infrastructures, engineers frequently encounter issues such as SFP modules not being detected, no link light after installation, or unstable fiber connections. These failures are rarely caused by “defective products” alone. More often, they result from environmental factors, compatibility issues, or improper.