I am looking at running 2 Cisco N2148 switches at the top of each cabinet but I am concerned with airflow. Has anyone employed these in server cabinets ?
They are front to back cooling units but they only extend 1/2 way into the cabinet - so the exhaust end is flush to the rear rails but the intake end is in the middle of the cabinet. I am concerned that they will be taking in any hot air that makes it way to the top of the cabinet.
You raise a very valid point - personally, I've not had any issues running any switches that are mounted in the rear of the rack with the air flow design "the wrong way round".
However, if you are supoer concerned, why not just cable everything to the front of the rack with slightly longer network cables?
Unfortunately so much Cisco hardware is not user Data Center friendly when it comes to air flow. Cisco claims that their hardware is designed for high temperature operation, so there is a low risk of failure. I always remember the electronics rule “For every 10oC you increase the temperate of a device, you halve the life span”.
If you can’t get the air flow correct, don’t install it that way.
According to the manual, the 2148 switch can accept input air as warm as 104F (40C). If your racktops are hotter than that, install auxiliary fans. We run similar switches in the tops of our server racks with no problem.