Using ethtool on AHV and XenServer will help with retrieving information like vendor, model, part number, serial number, transceiver type, cable length, connector type, signal quality, and more. SFP stands for (Small Form-factor Pluggable). It is a compact, hot-pluggable transceiver module used for both telecommunication and data communication applications. Figure 1 Schematic Diagram of Optical Module Connected to Server Network Card 1. It takes the device name (like swp1) as an argument. See man ethtool(8) for details. When an SFP OID is present then a module is plugged in.