Run the following command to view basic identification information of the inserted optical module: show fiber-ports optics-info <slot/port> The output includes module type, part number, vendor name, serial number, transmission rate, and other information derived from the. Run the following command to view basic identification information of the inserted optical module: show fiber-ports optics-info <slot/port> The output includes module type, part number, vendor name, serial number, transmission rate, and other information derived from the. The Cisco Small Business Series Switches allow you to plug in a Small Form-factor Pluggable (SFP) transceiver in their optical modules to connect fiber-optic cables. Once the transceiver and fiber optic cable are plugged in properly in the switch optical module, the Optical Module Status page of. When optical modules operate on a switch, it is usually necessary to read the module's internal information to understand its working status—such as connection status and real-time metrics like optical power and temperature. Additionally, identifying module information helps detect coding. If you run fiber or copper uplinks in a small office, home lab, or data closet, SFPs (and SFP+) are the little parts that keep your links alive. This guide gives a practical, CLI-focused workflow for checking SFP health and diagnostics on Cisco switches, shows the exact commands you'll use. How to check fiber ports in cisco switch? 1. Connect to the Cisco switch using a console cable or through a remote management interface. Enter the privileged EXEC mode by typing "enable" and providing the enable. Digital Optical Monitoring (DOM) is a feature that allows for the real-time monitoring of various physical and operational parameters of fiber optic transceivers, such as transmit power, receive power, temperature, laser bias current, and voltage. This guide provides complete, step-by-step CLI commands to view module type, DOM/DDM diagnostic data.