Before you jump on the quiet fan train insure you fully understand what the maximum operating temperature is for the hardware on hand.
Read the specifications as to operating temperature for the hardware.
Many Enterprise 1U switches have jet plane like fans because they generate a lot of heat at idle and while under high load. Before the energy star / green programs were adopted by current hardware makers the vast majority of them did not use PWM fans which ramped up and down based on thermistor temperatures.
Generally speaking quieter fans move less air and thus will generate more heat! Several great ideas have already been offered by other forum members as such here are a few more to consider / use if a quieter fan is in use:
- Flow: If the switch does not have baffles to direct air flow. You can make your own baffles to insure cool air is drawn over the heat generating parts.
- Heat Transfer: Applying thermal paste, thermal pads, and heat sinks attached to key components on the motherboard and then to the frame will help dissipate more heat. Thermal pads must be applied under the internal top case to isolate any heat sinks to prevent a short and personal electrocution.
- Push / Pull: If the switch has only exhaust fans. Install another fan to push (suck) air into the internal casing. Some servers use tandem fans paired together to generate more CFM in sync. While others only spool up upon a primary fan failure. A similar tandem fan configuration can be applied if space is available and the fans are consuming the same (current / amps) as a single OEM fan.
- Mounting: Normally devices are separated by 1U spacing top & bottom. If this is the only appliance that generates heat mount it at the top of rack. If the switch is installed on a table insure it’s sitting at least 1U away from the surface.
Filtering: There are countless sound absorbing products that can be applied to walls, cabinets, and enclosures. Depending upon the amount, type, thickness, etc. It’s easy to reduce 3~6 dB.
using the same.
Regardless of all the above (possible) solutions. Document what the idle temperature is vs full load with accurate
tools to obtain a baseline. Once known, make small changes and measure the same again to validate all is well.
Every switch will indicate it’s internal temperature from basic to advanced via CLI / Webpage. Compare this to your measured temperatures to validate the same.
Good luck . . .
