Better Control Over Fan Speeds on CCR2116

RouterOS General
1

I am experiencing an issue with the fan speeds on my CCR2116 router. The fans seem to ramp up and down arbitrarily even when the temperatures are quite low, leading to unnecessary noise. Below are the current readings from the system health check:

[a@gw01] > /system/health/print
Columns: NAME, VALUE, TYPE
 #  NAME                VALUE  TYPE
 0  cpu-temperature     48     C
 1  sfp-temperature     71     C
 2  switch-temperature  39     C
 3  fan-state           ok
 4  fan1-speed          6990   RPM
 5  fan2-speed          7080   RPM
 6  fan3-speed          6735   RPM
 7  fan4-speed          6840   RPM
 8  board-temperature1  40     C
 9  psu1-state          ok
10  psu2-state          ok




[a@gw01] /system/health/settings> print
    fan-full-speed-temp: 65C
        fan-target-temp: 65C
  fan-min-speed-percent: 0%
   fan-control-interval: 30s

As you can see, the temperatures are within a reasonable range, but the fan speeds are still quite high, which results in significant noise. Is there a way to better control the fan speeds to reduce noise when the temperatures are low? Any feature request / firmware updates to fix this or configuration tips would be greatly appreciated.

I am guessing the fan speed increase is due to my Mikrotik SFP+ module reporting a temperature of 71. I suppose as a temporary fix I could replace with an SFP+ module that doesn’t report the temperature. But maybe there is a way in the firmware to increase the threshold for SFP modules before ramping up the fans, which don’t even reduce the SFP+ module temperature…

2

Your fans are responding to the high-ish temperature of the SFP module

put an external FAN blowing over the module, and the internal ones will run quieter

3

I can’t figure out the sudden high fan speeds. Even when sfp-temperature is < 70 fan speed appears to randomly jump to 7000+ rpm.

MikroTik friends, is it possible to add slightly better fan control options to keep these units quieter when possible?

Columns: NAME, VALUE, TYPE
 #  NAME                VALUE  TYPE
 0  cpu-temperature     47     C
 1  sfp-temperature     65     C
 2  switch-temperature  37     C
 3  fan-state           ok
 4  fan1-speed          7020   RPM
 5  fan2-speed          7215   RPM
 6  fan3-speed          6765   RPM
 7  fan4-speed          6855   RPM
 8  board-temperature1  38     C
 9  psu1-state          ok
10  psu2-state          ok




Columns: NAME, VALUE, TYPE
 #  NAME                VALUE  TYPE
 0  cpu-temperature     48     C
 1  sfp-temperature     66     C
 2  switch-temperature  37     C
 3  fan-state           ok
 4  fan1-speed          3480   RPM
 5  fan2-speed          3720   RPM
 6  fan3-speed          3435   RPM
 7  fan4-speed          3555   RPM
 8  board-temperature1  39     C
 9  psu1-state          ok
10  psu2-state          ok
4

try this

/system health settings
set fan-min-speed-percent=10%