The device status LEDs is one of the easiest ways to mark signs of trouble on a network. The NICs, hubs, routers, and switches have these small indicators that warn the users if anything is going wrong. In this article, we are going to examine some of the common networking devices LEDs.
Ethernet Port Status LEDs
The computers connect to a network using a Cat 5/6 cable and Ethernet interface. Most Ethernet interfaces have one or two LED link indicators next to the interface. Generally, a green LED means a good connection and a blinking green LED indicates network activity. If the link light is not glowing its mean there is a problem with the network cable or the network itself. The switch port has also in indicators. If one or both LEDs are not glowing, use a different cable. The following table illustrates most host computers LEDs.
Network Device Status LEDs
If you have seen the network devices hub, switch, and routers you can notice multiple LEDs on the front of each device. These multiple LED indicators provide a quick status view for network operators and administrators. Each port has one or two dedicated LEDs. For example, a Cisco Catalyst switch has several status LEDs helping network administrators to monitor system activity, performance, and timely troubleshooting. When the switch is functioning, the status LEDs are generally glowing green and glowing amber when there is a malfunction.
The Cisco ISRs also uses status LEDs of various types to provide status information. The status LEDs also helping the network administrator for timely troubleshooting over network malfunctions. All network devices have a unique set of LEDs. For the descriptions of LEDs read the device-specific documentation. The following present the general guideline for network devices LEDs and some cases maybe it is different.