I love Supermicro’s motherboards!
They are built like a tank, excellent quality, pretty good support and good documentation … That is, until you’re trying to build a silent system based on a server board with some Noctua’s slow spinning fan (the gray ones).
Try it: Connect few of them to the board, and your IPMI UI will freak out, and it will complain about those fan that sometimes have 0 RPM, sometimes 400-500, sometimes 1000, and repeat. If you’re using ESXI/vSphere, you’ll be really annoyed from all the warnings!
So, how can we fix that? easy, follow these steps:
- Download the IPMICFG utility for your OS from this site (you’ll need to register), and extract the file on the host machine.
- Download the User Guide and follow the installation instructions based on your OS.
- SSH into the machine and become root
- The next part is important: in your IPMI Web UI, go to Server Health and select “Sensor Readings” – check which sensor is marked with a red box. Write down the sensor name
- On the host, run the IPMICFG command (per the userguide) with the parameter sdr. Example: ./IPMICFD -sdr
- Look at the list the command produced and find the number of that sensor.
- Time to delete the sensor (don’t worry, the fan will continue to work): run the same command but add -del <sensor number> so if, for example, the sensor number is 1234, then the command would be: ./IPMICFG -sdr -del 1234
- If you’ll look at the IPMI web UI, you might be surprised to see the naughty sensor still appears and gives false alarms. The solution is simple – reboot the IPMI (it won’t reboot the server and the server will continue to work uninterrupted) using the command: ./IPMICFG -r
- That’s it! You shouldn’t get more alarms.