Quick note,
Installed some HP FlexFabric 5700 switches the other day and I was getting a red LED on the front, and a status message in the CLI
HPE DEV/1/FAN_DIRECTION_NOT_PREFERRED: -Slot; Fan 1 airflow direction is not preferred on slow 1, please check it.
This is a pretty common issue if you chose Back-to-Front fans for your build.
The part numbers for the 5700 series are as follows (taken from this document);
HP 58x0AF Bck(pwr) – Frt(ports) Fan Tray – JC682A
HP 58x0AF Frt(ports) – Bck(pwr) Fan Tray – JC683A
The fix is quite simple
To display the airflow configuration;
display fan slot {slot No,}
To change the configuration
Fan prefer-direction slow 1 port-to-power
Below is a screenshot showing the error, the display command and the resolution.
There is also an official guide here from HPE
Regards
Dean
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