I have an old RB2011UiAS-2HnD, where I want to turn off the very bright blue SFP-Cage LED, because it lit up the whole room in the night. In WinBox, I saw there is a LED menu, to control various LEDs. Unfortunately, it looks like my RouterBoard do not support changing settings here (Warning says: “This feature is not supported on this board! (LED Settings)”)
Here are my questions:
Is this just not supported by RouterOS, because it is such an old device? Or are the LEDs not controllable by software (because the LEDs are directly connected to 5v/GND on the PCB)?
Is there another way to turn off the LED without desoldering it from the board?
Some devices do not have led support, some have only PARTIAL control, i.e. some led(s) can be controlled, others cannot.
Short of de-soldering the non-controllable leds, usually they are covered/obfuscated with black tape or if not enough, with a small piece of black acrylic/plastic.
If you go for the soldering iron, It would IMHO make more sense to solder a resistor in series with the led in order to reduce the emitted light.
I used to have that router, and now I use a RB4011, and I also have a computer with blue power led.
I recognize the problem and did the same as written above: a piece of black tape to cover the LED. It can still be seen, but it no longer lights up the room.
@jaclaz Yes, adding a resistor to the blue LED (or replace it) would do the trick.
But just for curiosity: Do the router board have some GPIO pins I can control from WinBox? I see that the KNOT device have some GPIO pins exposed, but it would be awesome to have some pins on other boards as well. Maybe directly from the microcontroller IC?
Newer devices allow the LEDs to be controlled, to different levels. That is why you see options in RouterOS. Some devices can turn off all LEDs, some a subset of them, e.g. not the power LED.
In the RB2011 days there were lots of features controlled by the CPU, like a beeper, an LCD touch screen, etc that used GPIO pins. On more modern devices those are all gone, probably freeing up pins for purposes like this. But these are not accessible for the user… There is usually only a single LED that you can arbitrarily turn ON or OFF (the “user LED”) which of course is connected to a GPIO pin.
I don't think there Is anything controlled/controllable by Winbox on MOST Mikrotik devices, set aside the controllable led(s).
On some devices that have one or more PoE ports these can be used to command a relay (not directly, through a board/circuit due to resistance check) but that's It.
The Knot Is a "particular" device expressly made for tinkering with IOT and similar so It has features that other "normal" devices completely miss.
but the answer is: a piece of duct tape.