ESXi Host Not Responding in vCenter due to Automatic Operating System Shutdown from Overheat Condition

Products

• VMware vSphere ESXi

Issue/Introduction

An ESXi host intermittently or suddenly transitions to a "Not Responding" state within vCenter Server. The following symptoms are observed:

• vCenter alarms triggered: "Host connection and power state" and "Host hardware temperature status."
  

• The Direct Console User Interface (DCUI) is inaccessible as the host is powered off.

• Hardware Event Logs (e.g., HPE iLO, Dell iDRAC) report: Automatic operating system shutdown due to Overheat Condition.
  

Environment

• VMware ESXi 8.0

• HPE ProLiant Servers (iLO firmware managed)

Cause

The physical server experienced a thermal event where temperatures exceeded the predefined safety thresholds.

The Integrated Lights-Out (iLO) firmware or equivalent Baseboard Management Controller (BMC) triggered a graceful or immediate shutdown of the operating system to prevent permanent hardware damage.

Resolution

• This is a physical hardware and environmental issue that cannot be resolved through software configuration.
• Engage the Datacenter Team to inspect cooling systems and airflow management for the affected rack/chassis.
• Engage the Hardware Vendor (HPE) to check chassis fans and thermal health of components.