Exam NSE5_FSW_AD-7.6 Topic 2 Question 41 Discussion

According to theFortiSwitchOS 7.6 Administration Guide(specificallyPage 178) and theFortiSwitch 7.6 Study Guide, the Spanning Tree Protocol (STP) is the fundamental protocol used to manage redundant paths in a Layer 2 network. In the scenario described, where every FortiSwitch connects to every other FortiSwitch, afull Layer 2 meshis created. This architecture inherently produces multiple physical switching loops that, if left unmanaged, would cause catastrophic broadcast storms.
STP is responsible for detecting these loops by exchangingBridge Protocol Data Units (BPDUs). It then mathematically calculates a loop-free logical topology by placing redundant ports into ablocking (discarding) state while keeping primary paths in aforwardingstate. WhileMCLAG (Option A)provides node-level redundancy and eliminates STP delays by allowing two switches to appear as one, it is not a standalone solution for a global full-mesh topology. In fact, Fortinet MCLAG explicitly relies on STP through the mclag- stp-aware feature to detect and prevent loops caused by connections outside the Inter-Chassis Link (ICL).
Therefore, although MCLAG and LAG increase bandwidth and availability,STPremains the required underlying mechanism to maintain network stability in any highly redundant mesh environment. "Full mesh HA" (Option C) is not a defined feature in FortiSwitchOS 7.6.