Using IPMITOOL to disable a fan sensor

Question

I am no longer using FAN3 in my system. But there is still a lower/upper sensor bound set for it. I had set that previously using ipmitool.

How can I use ipmitool to set all the values back to na instead of 0?

Because currently, the lower threshold causes assertions, and all fans to run at full blast.

FAN1             | 1300.000   | RPM        | ok    | 100.000   | 200.000   | 300.000   | 3000.000  | 4000.000  | 5000.000  
FAN2             | na         |            | na    | na        | na        | na        | na        | na        | na        
FAN3             | 0.000      | RPM        | nr    | 0.000     | 0.000     | 0.000     | 3000.000  | 4000.000  | 5000.000  
FAN4             | na         |            | na    | na        | na        | na        | na        | na        | na        
FANA             | na         |            | na    | na        | na        | na        | na        | na        | na        
FANB             | 1300.000   | RPM        | ok    | 100.000   | 200.000   | 300.000   | 3000.000  | 4000.000  | 5000.000

I want FAN3 to read na like FAN2, FAN4 and FANA do.

Things that I have tried:

$ sudo ipmitool sensor thresh FAN3 lower 0 0 0 (does not stop the assertion)
$ sudo ipmitool sensor thresh FAN3 lower -1 -1 -1 (not accepted)
$ sudo ipmitool sensor thresh FAN3 lower na na na (not accepted)

This is on a Microdata X11-SRM-F running Ubuntu.

The assertion that causes full blast fans:

$ sudo ipmitool sel list
   1 | 09/30/2020 | 23:39:46 | Unknown #0xff |  | Asserted
   2 | 10/08/2020 | 17:38:54 | Fan #0x43 | Lower Critical going low  | Asserted
   3 | 10/08/2020 | 17:38:54 | Fan #0x43 | Lower Non-recoverable going low  | Asserted
   4 | 10/08/2020 | 17:43:50 | Fan #0x43 | Lower Critical going low  | Asserted
   5 | 10/08/2020 | 17:43:50 | Fan #0x43 | Lower Non-recoverable going low  | Asserted

score 1 · Accepted Answer · edited Mar 05 '21 at 09:34

A reboot would keep the fan assertion enabled.

However: physically switching the computer off at the power supply did the trick: FAN3 is now listed as na.

So you need to actually cut the power before the ghost fan goes away.

Alternatively, if ipmitool works for your system you can utilize a cold mc reset to clear out that status without removing power from your system. You will have to wait about 70-90 seconds after running this command to work with your IPMI again. Run the command as follows:

$ ipmitool mc reset cold

Using IPMITOOL to disable a fan sensor

1 Answers1