The 3rd-party monitoring software sent an ICMP ping, but the ESXi host may have failed to respond.

Products

• VMware vSphere ESXi

Issue/Introduction

The 3rd-party monitoring software sent an ICMP ping, but the ESXi host failed to respond, causing the monitoring software to trigger an error indicating that the ESXi host is down.

Environment

ESXi 

Cause

The ESXi host may have been in the process of shutting down or booting up. While powered off, it cannot respond, and it may also fail to respond to ICMP ping requests during the boot-up process.

Resolution

This is expected behavior.

You can confirm whether the ESXi host was down by verifying the /var/log/vmware/vmksummary log.

2025-11-11T05:34:09.100Z No(13) bootstop[332920427]: Host is powering off
2025-11-11T05:47:05.874Z No(13) bootstop[2102143]: Host has booted

NOTE: The preceding log excerpts are only examples. Date,time and environmental variables may vary depending on your environment.