Execute the following command to view detailed interface and optical module status: ethtool The output includes interface rate, module rate, link status (Link detected: yes is required for normal module operation), and interface configuration details. Where is the optical drive with. Optical transceivers can be used on switches, routers and network adapters (fiber network cards). It is used to connect a computer system to a fiber-optic network. It supports both single-mode and multi-mode fiber cables and is. Linux (RHEL), you can use the ethtool command. Use th trol the network driver and hardware settings. Not all. DDM (Digital Diagnostics Monitoring) is a feature that is included in optical modules, such as SFP, SFP+, QSFP, and QSFP+ transceivers.