The CMC automatically raises and lowers the fan speed to a setting that is appropriate to keep all
modules cool.
If a single fan is removed, all fans are set to 50% speed, if the enclosure is in Standby mode. If the
enclosure is powered on, removal of a single fan is treated like a failure (nothing happens).
Re-installation of a fan causes the rest of the fans to settle back to a quieter state.
Whenever communication to the CMC or iDRAC is lost, for example during a firmware update,
the fan speed is increased and creates more noise.
PowerEdge M1000e Technical Guide
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