vCenter Server and ESXi health results do not match when you have mixed or partitioned vSAN clusters

Products

• VMware vSAN

Issue/Introduction

If your vSAN cluster is partitioned or includes hosts with different ESXi versions, the health check results reported by vCenter Server might not match the results from ESXi hosts. Typically, the vCenter Server health results can be posted by both APIs or the vSphere Web Client. For the hosts, APIs or esxcli commands can provide the results.

Partitioned Cluster

When the cluster is partitioned, the inconsistencies between the vCenter Server and ESXi health results might occur for the following reasons:

• vCenter Server can detect the cluster partition and present the health check result of each partitioned sub-cluster.
• The ESXi host is able to detect and present the health status of the sub-cluster it belongs to. The host is not able to report the issues in another cluster.

The following table illustrates the difference between the health check results generated by vCenter Server and the host.

 

Health Check ID	vCenter Server APIs	Host APIs
vSAN cluster partition (Network)	Red	Green

 

Mixed Version Cluster

The host level APIs are only exposed on hosts with the vSAN 6.6 version. For hosts with the vSAN version 6.5 or earlier, the vSAN health check result might not be collected properly through host level APIs.

As a result, when the cluster is composed of the hosts with mixed versions, you might observe inconsistent results, as the following table illustrates.

Health Check ID	vCenter API	Host Level API
Hosts with connectivity issues (Network)	Green	Red
Physical disk health retrieval issues (Physical disk)	Green	Red
ESX vSAN Health service installation (Cluster)	Green	Unknown
Advanced vSAN configuration in sync (Cluster)	Red	Green
vSAN CLOMD liveness (Cluster)	Green	Red

Resolution

In the partitioned cluster, check vSAN health with the vCenter Server API. Make sure to pay special attention at the misleading health check information provided by the the host level API.

If your cluster includes hosts with different ESXi versions, upgrade the hosts to the latest version to get the correct health check results from the host level API.