r720 Fan 4 still running after shutdown

Hi,

I tried checking if there is any notes on such issue on R720 iDRAC version, but there is no known issue stated. There are a few things to I would like to check. Does Fan 4 spins after a few minutes of wait? What happen if the power cables are pulled and installed back, does the fan spin? When the system is off, are there any LED lid? If you were to swap Fan4 and Fan3, does the issue follow the slot? Do you have iDRAC access? Have you tried resetting the iDRAC? 

Hello joey, thanks for the reply.

The problem doesn't follow the fan, its always slot 4.

Fan spins up immediately power cable is plugged in. Every time.

The inner iDrac LED is lit when the system is off but power still connected.

Yes iDrac has been reset (and NVRAM wiped etc) I've got physical access to the machines.

I've read that fan 4 stays spinning on low speed in order to cool the iDrac. So for the 2nd machine it might be normal behaviour? Is that correct?

Hi jms99.

The iDRAC is running all the time, true, so it needs to be cooled.

I haven't heard about it yet tbh, but the more I think about it, the mere it makes sense.

I recommend that you update the iDRAC on the 2nd system also to the latest version to lower the speed of the fan.

If you come across this article again, where you read it, feel free to share it

BR
Stefan

Hi Stefan. Thanks for the input. I suspect it could be some sort of FW corruption - hopefully updating it will fix it.

The info about fans running for the iDrac was on a reddit thread I think, can't find the link.

Found this thread though that suggested down grading FW fixed it

https://www.dell.com/community/Rack-Servers/Dell-R720-FAN-4-still-runs-after-shutdown/m-p/6194496#M4108

Hi,

Can I know if the fan do stop in period of time, have you monitored that? like it spins for about 5 to 10 minutes? Has the other firmware in the server have been updated? eg: BIOS. 

Reset of iDRAC, what kind of reset would it be? Have you tried RACADM hard reset? 

Try this, remove all components except the below and the fans. Then try connect the power cable and check if fan 4 still spins:

•One Power Supply
•Control Panel (for power button functionality)
•Working cable connection between control panel and system board
•One Processor (CPU) in socket CPU1 (minimum for troubleshooting) 
•One Memory Module (DIMM) installed in socket A1
•System Board
•Backplane (for R720xd control panel connection)

@jms99 , As @DELL-Stefan R mentioned some components (E.g. iDRAC, NDC) on the server will be running even if server is powered off. Some of the FANS will be running at low RPM for cooling of these components. This is dependent on the server configuration as well. I would recommend to update iDRAC FW to latest on system 1 also and check whether FAN running at low RPM after the upgrade.

The fan on both machines stay on constantly, it doesn't stop, 1 day later still on.

I think I must have only done a soft reset (via F2 menu, or Lifecycle Controller, can't recall which), I haven't used RACADM. I will try it, if that fails I'll try the troubleshooting steps you suggest.

Hi,

Thanks for updating us on the issue that you're having. A good share. I'll put a note on the case notes for engineering to take note. 

Hello all,

I noticed the same issue today after updating my R720. With firmware 2.40.40.40 (after shutdown) the number 4 fan isnt powered up and spinning. After updating to the FW 2.65.65.65 it does spin. I also tried FW 2.63.60.62 same thing. All that running the latest BIOS (2.9.0)

Withing a minute of shutdown the number 4 fan starts to spin at low rpms. I tried changing No4 with No3 fan and various other combinations with the same result. I read the comment above that it may be for cooling of the idrac but this means that with FW 2.40.40.40 and before it wasnt needed?
It seems like a firmware issue and ill revert back to 2.40.40.40 for now. If you can have a look please and maybe fix it? Thanks alot!

I can confirm all of the same things on my own R720. Fan 4 always runs at low RPM when the power is off. It does not matter what fan is swapped into that slot, it is slot 4 that is powered all the time. Also, previously there was an ability to manually adjust the fan % power that has been lost with later firmware. Because my boxes live in a room that is colder than necessary most of the time even the low 20% range is too high most of the time. They used to be at 10% with automatic increase on demand, but now I can not manually adjust the fan tolerances with the latest update. Apparently a lot of the fan control is now removed with the latest revisions.

Having the same problem since I've updated.

In the iDrac Settings, thermal options, change the fan settings to fan speed offset.

100% confirmed to be a firmware problem, went through everyone starting with 2.40.40 and finishing with 2.65.65: Last one working good is 2.41.40, there's something implemented in 2.50.50 breaking the 4th fan or either its sensor. Its not a fan problem, swapped with another one and it does the same.

Hi @elfriscia,

Thanks for the troubleshooting info that you have found out. 

Can I know how many R720s do you have? Only one? 

Can you let me know if the fan still spins after you have shutdown the server and waited for more than 15minutes. Have you tried resetting the iDRAC? Is BIOS up to date?