Use the vSAN health service to monitor the health of your vSAN cluster.

You can use the vSAN health checks to monitor the status of cluster components, diagnose issues, and troubleshoot problems. The health checks cover hardware compatibility, network configuration and operation, advanced vSAN configuration options, storage device health, and virtual machine objects.

The Skyline Health displays View Health History, Overview, and vSAN Health Finding Categories. Expand each health finding category for details.
You can use Overview to monitor the core health issues of your vSAN cluster. You can also view the following:
  • Health check count based on the health status
  • Primary issues with the nested issues. These nested issues might be caused by the primary issue and resolving the primary issue might solve the related nested issues.
  • Other standalone health issues without any dependency

The vSAN health checks are divided into categories. Each category contains individual health checks.

Table 1. vSAN Health Check Categories
Health Check Category Description
Hardware Compatibility Monitor the cluster components to ensure that they are using supported hardware, software, and drivers. To identify a device with duplicate PCI ID in the vSAN cluster, see Examine Health Warning of an Unidentified NVMe Device.
Performance Service Monitor the health of vSAN performance service.
Network Monitor vSAN network health.
Physical disk Monitor the health of physical disks in the vSAN cluster.
Data Monitor vSAN data health.
Cluster Monitor vSAN cluster health.
Capacity utilization Monitor vSAN cluster capacity.
Online health Monitor vSAN cluster health and send to VMware’s analytics backend system for advanced analysis. You must participate in the Customer Experience Improvement Program to use online health checks.
vSAN Build Recommendation Monitor vSAN build recommendations for vSphere Lifecycle Manager.
vSAN iSCSI target service Monitor the iSCSI target service, including the network configuration and runtime status.
Data-at-rest encryption Monitor vSAN data-at-rest encryption health.
Data-in-transit encryption Monitor vSAN data-in-transit encryption health.
File Service Monitor vSAN file service health.
Stretched cluster Monitor the health of a stretched cluster, if applicable. For more information on "Witness appliance upgrade to vSphere 7.0 or higher with caution", see the VMware knowledge base article at
Hyperconverged cluster configuration compliance Monitor the status of hosts and settings configured through the Quickstart workflow.

vSAN periodically retests each health check and updates the results. To run the health checks and update the results immediately, click the Retest button.

If you participate in the Customer Experience Improvement Program, you can run health checks and send the data to VMware for advanced analysis. Click the Retest with Online health button.

For more information about vSAN health checks, see the VMware knowledge base article at

Monitoring vSAN Health on a Host

The ESXi host client is a browser-based interface for managing a single ESXi host. It enables you to manage the host when vCenter Server is not available. The host client provides tabs for managing and monitoring vSAN at the host level.
  • The vSAN tab displays basic vSAN configuration.
  • The Hosts tab displays the hosts participating in the vSAN cluster.
  • The Health tab displays host-level health checks.

Viewing vSAN Health History

The vSAN health history helps you examine health issues by querying the historical health records. You can only view the historical health data of a cluster. By default, the health history is enabled. To disable the health history, select the cluster and navigate to the Configure > vSAN > Services > Historical Health Service and click Disable. If you disable the health history, all the health data collected on the vCenter Server database gets purged. The database stores the health data for up to 30 days depending on the available capacity.

Using the Skyline Health view, you can use the toggle button to view the health history and then select a time range. The start date of the time range must not be earlier than 30 days from the current date. The end date must not be later than the current date. Based on your selection, you can view the aggregated health status of each health check. Click a health check to view the history of that health check within a certain time period. The historical data is displayed as a graphical representation with green circles, yellow triangles, and red squares showing success, warning, and failure respectively. The detailed information about each health check result is displayed in a table.