kjstech
3 Argentium

FX2 Chassis fans startle us and periodically go full speed (sounds like a system reboot)

Ocassionally maybe twice a day we hear our Dell FX2 server chassis fans ramp up to full speed and it sounds EXACTLY like a reboot or when you first power on a chassis.  Its a startling sound because we all look at each other like what the ....  Luckily there are no automatic reboots, BSOD (or PSOD's I should say - they run vmware). 

We originally thought it was our EMC VNX5200 that was racked above it, but we recently upgraded to an all flash Tegile array, removing the VNX5200.  Now we still hear these occasional fan ramp ups.  Is it possible to disable this, figure out why its happening or maybe this is a bug fixed in a code upgrade?  I checked the Chassis Management Controller and there are no critical, non-critical or informational alerts/messages.  Theres nothing recent in the CMC Hardware Log either.  Chassis firmware is 1.30  There is nothing special about the fan configuration.  In fact Fan Offset is set to Off.

 

Let me know your thoughts.  Thanks!

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Moderator
Moderator

Re: FX2 Chassis fans startle us and periodically go full speed (sounds like a system reboot)

Hi,

Can you private message me the service tag so we can get some additional information?

 

Does the load on the servers change at all? Updating the CMC may also help. http://www.dell.com/support/home/us/en/19/drivers/driversdetails?driverId=408P2

Thanks,
Josh Craig
Dell EMC Enterprise Support Services
Get support on Twitter @DellCaresPRO
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kjstech
3 Argentium

Re: FX2 Chassis fans startle us and periodically go full speed (sounds like a system reboot)

I logged into the cmc today when the fans ramped up this afternoon and kept refreshing the page throughout the process as they slowly came back down to near silent.

 

When the fans were screeming the input power was at 720W.  They slowed down a little bit and a page refresh indicated 610W.  Each time the fans slowed down I refreshed and recorded the Input power:

573W

544W

528W

490W

And finally when it was near silent as it currently sits, the CMC is showing 425W.

 

This CMC is on firmware 1.3.

 

I have a new chassis above it on firmware 2.0.  It has 4 FC640 blades.  I refreshed this one the entire time and its power level fluctuated between 900W and 876W, however the fans are near silent on that chassis.

 

BOTH chassis indicate an power cap of 3371W and power alerting set to redundancy only.  Both are connected to 206 VAC PDU's.  The difference is the one making all the noise has 1600W power supplies, using C13 to C14 connectors.  The new FX2 chassis uses 2000W power supplies, using C14 to C19 power cords.

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Re: FX2 Chassis fans startle us and periodically go full speed (sounds like a system reboot)

Can you update CM<C FW to 2.0 and check the behavior. IF you have FC640 blade then CMC FW need to be at 2.0. Check below note from CMC 2.0 FW release note

- Supporting PowerEdge FC640 sled on the PowerEdge FX2/FX2s chassis.

Thanks-


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