Checking optical attenuation at switch interfaces

To check SFP light levels, use CLI commands such as show interface transceiver details (Cisco), show interfaces diagnostics optics (Juniper), or ethtool -m (Linux) to read Digital Optical Monitoring (DOM) data. These values are retrieved from the transceiver's EEPROM via I2C and include Rx/Tx. This article provides instructions on how to view the Optical Module Status on your switch through the Command Line Interface (CLI). How to test fiber optic cable cisco switch? How to check fiber ports in cisco switch? How to. 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. Note: In this example, te1/0/3 interface is used. [pdf]