I have a MSX6005 12 port FDR switch that I’m installing and I noticed the fans in it run at full speed all the time. The switch is really loud and vibrates allot. The computer room its going in is set to 70F right now so its not overheating and all the LED’s are green on the front. I have a MSX6036 that I use for internal testing and it is really quiet. I updated the firmware on the switch to 9.2.8000 but that didn’t help.
the MSX6005 is an un-managed switch means, it has no internal management board and therefore there was no way to run any logic that sets the fan speed according to temperature. Because of this the fan always runs at top speed to make sure the unit stays cool.
It also might be that you have a defective fan (since you reported it also vibrates), so i suggest you also check in with Mellanox support mailto:firstname.lastname@example.org and see if they can troubleshoot and determine whether you have a defective fan.
It might be that in the future the guys will decide to notch it down a bit but it is not clear if this is happening. If I hear anything, I will post.