Dell’s FN I/O Modules (FN IOMs) are integrated devices that sit in the rear of the FX2 chassis and behave like traditional network switches. The FN IOMs provide 8 x 10GbE internal ports to the connected server nodes while offering 4 x 10GbE external links for upstream connectivity. What makes the FN I/O Module unique is that it supports 5 operational modes: Standalone (SMUX), VLT, Stacking, Programmable MUX (PMUX) and Full-switch. Below are details on each of these modes.