Diagnostics for VMware Cloud Foundation: ESX Health: Hardware Sensor Health

Products

• VCF Operations

Issue/Introduction

The vSphere software stack obtains hardware sensor information from the BMC (Baseboard Management Controller) using IPMI (Intelligent Platform Management Interface). When ESXi boots on a hardware platform, it loads a native IPMI device driver, that is used to retrieve the following data:

• BMC configuration
• FRU (Field Replaceable Unit) information
• SEL (System Event Log) entries
• SDR (Sensor Data Record) details

This data provides visibility into the operational state of hardware components such as fans, power supplies, and temperature sensors. If a sensor reports a degraded or unhealthy state, the vSphere Client generates a warning or alert.

Environment

VCF Operations 9.x

Cause

Hardware sensor health issues may occur due to:

• Sensor data not updating correctly in the vSphere Client.
• Persistent System Event Log (SEL) entries that continue to trigger alerts.
• Outdated or unsupported BMC firmware impacting IPMI communication.
• Genuine hardware faults causing recurring or severe alerts.

Resolution

Follow this diagnostic workflow:

1. Refresh Sensor Data

• • Navigate to the affected ESXi host in Hosts and Clusters.
  • Under Monitor > Hardware Health, click Refresh to reload sensor readings from the BMC.

2. Reset System Event Log (SEL)

• •    Via the vSphere Client: Navigate to Monitor > Hardware Health > System Event Log and click Reset Event Log.
  •    Via Command Line: Use the 'esxcli hardware ipmi sel clear' command.

3. Consult Hardware Vendor

• • Ensure the BMC firmware is up to date.
  • Consult your hardware vendor for information on firmware updates, or investigation of recurring alerts that may indicate underlying hardware issues.

Additional Information

For further details on monitoring hardware sensors and managing the SEL, refer to the following documentation:

• Monitoring Host Health Status
• View System Event Log
• KB 1033725