When the iDRAC, BMC or CMC/OME-M loses connection to the sensor suite, the fans return to the unmanaged speed (full) to protect the system from overheating.
This is the reason why you can hear the fans spin up before coming back down when turned on first. It takes a few minutes for the iDRAC, BMC, or CMC/OME-M to boot up and start regulating fan speed.
Hi there. In this video we'll cover possible Power edge fan irregularities caused by disrupted communication with the system's Ira. Disruptions can be caused by a lost connection from the IAC, BMC or CMC to the sensor suite. The fans will return to the unmanaged default full speed to protect the system from overheating. This is the reason you can hear the fan cycle at full speed when first turned on, as it takes a few minutes for the IDAC, BMC, or CMC to boot up and start regulating the fan speed.
To troubleshoot this issue on an iDRAC system, first try restarting the iDRAC by pressing and holding down the I button on the front panel for at least 16 seconds. Stop pressing the button when the cooling fan starts spinning at full speed, and the front LCD, if present, turns off. Now the i jack restarts without changing any saved settings. It may take a minute or longer until the remote controller restarts. If the i Jack reset didn't work and the fans are still spinning at full speed, you can try a hard reset of the system.
To do this, power down the server. Remove the power cable. Press and hold the power button for 10 seconds. Reconnect the power cables. Wait for about 2 minutes. And turn the server back on. For systems that contain a chassis management controller or open manage enterprise management, follow the failover procedure to fail over to the other units. If only a single CMC or OMEEM is installed, remove the module from the chassis, wait for 2 minutes, reinsert the module, and wait for a further 20 minutes.
If reseating the module or the failover did not work, a restart of the chassis will be required for a complete reinitialization. Schedule downtime for all servers and attached devices that rely on the chassis being up. Power the servers off, then power the chassis off and remove the power cables. Wait at least 10 minutes, or press and hold the power button if available.
Reconnect the power cables and turn the chassis back on. Wait for a further 20 to 30 minutes before turning the servers back on. If you're still experiencing the same fan noise at this point, check the knowledge base articles for further steps to diagnose the issue. And that's it.
Thanks for watching.
