"Host connection and power state" alarm is triggered after vpxd service is restarted

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

• "Host connection and power state" alarm is raised for a host which heartbeat packets do not reach vCenter Server. This is normal behavior.
• After restarting vpxd, the host state is recovered to Green though the heartbeat packets from the host still do not reach vCenter Server.

Environment

VMware vCenter Server 6.5.x
VMware vCenter Server 6.0.x

Cause

This can occur by unsupported configuration that ESXi host and vCenter Server fails to communicate through the heartbeat port. The default heartbeat port is 902/udp.

Resolution

Make sure that all required ports are allowed between ESXi hosts and vCenter Server or PSC.

* Required Ports for vCenter Server and Platform Services Controller
https://docs.vmware.com/en/VMware-vSphere/6.0/com.vmware.vsphere.migration.doc/GUID-F4F3E3DE-5DA2-49BE-BE4A-BFCA2EFF9FB4.html

Additional Information

Impact/Risks:
The host which previously raised "Host connection and power state" alarm may appear to be healthy after restarting vpxd even though the heartbeat still does not reach vCenter Server..