Controls Dell Server fan speeds over IPMI. Tested on a Dell R420.

Setting Up:

Make sure you have lm_sensors and ipmitool installed.

The IPMI interface has to be exposed to the host operating system, on iDRAC 7 Enterprise this can be enabled by ticking Enable IPMI over LAN in iDRAC Settings -> Network

Now you can access the IPMI directly from the host machine, using the dedicated idrac interface. (The IP is usually 169.254.0.1)

In order to add some obfuscation, credentials to access IPMI are stored in a .env file in the program directory. (More secure ways to input credentials are in the works). Format your .env like so:

HOST=<iDRAC IP>
USER=
PASS=

Building:

make fancontol
./fancontrol <fanspeed>

Usage:

Because of a limitation in IPMI, fan speeds can only be set to two values. A manual static value from 0-100% can be set, or you can hand fan speed control over to the server (this is loud!).

./fancontrol <fanspeed>

Set your desired fan speed in % and fancontrol will maintain that speed unless the server gets too hot (defaults to 70C). If no argument is provided, fan speed is set to 15%.

By default, the program refreshes the fan speed every 3 seconds and outputs temperature information to the console. It can optionally check for network connectivity and restart NetworkManager if needed.

Extra: start.sh is an example of how to run this program in the background