/var/log/syslog.log file reveals an entry similar to the following, indicating a shutdown initiated by the smad daemon:####-##-##T##:##:##.### Al(9) smad[#####]: The host is being shutdown due to Insufficient Cooling.
VMware vSphere ESXi 8.0
This behavior is expected when the hardware management agent detects a critical temperature or cooling issue on the physical server. The smad process is a core component of the HPE Agentless Management Service (AMS).
When the server's Baseboard Management Controller (e.g., HPE iLO) reports a temperature anomaly or fan failure, the AMS daemon running on the ESXi host triggers a graceful shutdown. This is a protective measure designed to prevent physical hardware damage caused by thermal events.
Because the shutdown is initiated by the hardware management agent in response to a physical environmental or hardware condition, the root cause must be investigated at the hardware level.
(Note) There is a known issue where specific versions of the AMS daemon or server firmware incorrectly report high temperatures (e.g., falsely reporting a SATA SSD temperature as 127°C).
For more details on this issue, please refer to the following HPE Advisory: