Multiple hardware sensors status shows as unknown and absent hardware's status shows warning on HPE Gen 10 servers

Products

• VMware vSphere ESXi

Issue/Introduction

To stop the sensors from generating false alarms.

• All the presence sensor state are displayed as unknown in Hardware monitoring Monitor->Hardware Status->Sensors.
• If the devices are physically absent on a server,
  • The device state might be displayed as warning: [Device] I/O Module n ALOM_Link_Pn or [Device] I/O module n NIC_Link_Pn
  • Warning alarm for the device could be raised.

Cause

HPE Gen10 servers, iLO 5 firmware 1.30 has new sensors which cause unspecified status for I/O Modules . For more information, see the HPE Customer Advisory

Resolution

The fix implemented is to ignore sensor warnings on iLO firmware prior to version 1.40.

To implement this fix upgrade to patch as below
ESXi 6.5 P04 -  patch esxi650-201912002. 
ESXi 6.7 P01 -  patch  esxi670-201912001. 

Workaround:
To workaround this issue downgrade the iLO5 firmware to 1.20.

Additional Information

There are some additional improvements in HPE iLO5 firmware 1.40. For more information see HPE advisory

Impact/Risks:
Requires a ESXi host reboot.