2012-Sep-3 - Link LED indicating lamp
Daily network one of the most common fault is the site can not get on the Internet problems. PC users or network maintenance personnel first thought LED PLC Lamp is to look at the card or switch ( or HUB ) indicator to judge whether the normal connection ( usually this is the fault diagnosis of the correct steps), then from the PC check software settings problem. But whether can through network or switch on the LED lamp to judge the cable or port problem? Practice has proved, it is precisely because of the LED gives instructions to make the wrong judgment, makes the troubleshooting in the wrong direction for troubleshooting to waste a lot of time. Then the LED lamp at the time of fault diagnosis can have what help?
Port on the most common LED light is green, sometimes yellow or other colors. The first thing to understand, different color LED lights, each manufacturer defines its function may be different. And the green LED lamp is the most common, it is what meaning? Green LED light does not shine, there is definitely a problem, which is the most direct and correct judgement. But green LED lights, if no problem? Regardless of NIC or switch ( HUB ) port has a transceiver two functions. Green LED lights indicated a signal coming in, but does not mean that the normal transmission signal. That is to say not only through the end of green LED lights on the judgment of transceiver is normal. Then to judge the transceiver normal depends on both ends of the green LED lamp. Usually switch ( HUB ) and PC are not together, one in the office, another in the room, so rapid examination of the ends of the LED lights are sometimes not convenient. Especially for those without good wiring mark case, in the engine room of the switch for a corresponding port and sometimes is not a simple thing.
As for the Yellow LED lights, some manufacturer is defined by said transmitted signal, some expressed or half duplex working mode. So the Yellow LED lamp judgment depends on user on the card or switch ( HUB ) understanding. If there is no understanding of NIC and the switch yellow LED lamp when the meaning, don't judge. It may be in the wrong direction and spend a lot of time. Statistical data shows, the switch port LED Dimmer Switch dab5d58ck and card working mode ( full-duplex and half-duplex ) does not match the accounts for a considerable part of the fault.
To sum up, simply look at the card or switches on a green or yellow LED light on cable, adapter or the switch port to judge is not desirable. Otherwise, from simple phenomenon and come to a wrong judgment, medal 2012 can make fault diagnosis go wrong and waste a lot of time. In addition, there are still some problems, such as series wound ( SplitPair ) cable, adapter or the low level switch is not available from the LED lamp to draw any conclusions, but these failures could lead to site appeared intermittently or very slow fault.