What does an amber LED on the port status indicate?

When an amber LED is observed on a port status indicator, it signifies that the port is blocked by the Spanning Tree Protocol (STP). The purpose of STP is to prevent loops in a network that can be caused by redundant links between switches. When a loop is detected, STP blocks certain ports while allowing others to remain active, ensuring a loop-free topology.

If the port is amber, it indicates that, while there is a device connected (link is present), that specific port is not active for data transmission due to STP intervention. This status helps maintain network stability and effectiveness by managing redundant paths in the network and preventing broadcast storms. Therefore, the interpretation of an amber LED in this context is essential for network management, allowing IT professionals to diagnose potential issues related to network design and configuration.