vSAN Health Service - Cluster Health - Advanced vSAN configuration in sync

Products

VMware vSAN

Issue/Introduction

This article explains the Cluster Health - Advanced vSAN configuration in sync check in the vSAN Health Service and provides details on why it might report an error.

Environment

VMware vSAN 8.0.x
VMware vSAN 6.0.x
VMware vSAN 7.0.x
VMware vSAN 6.5.x
VMware vSAN 6.7.x
VMware vSAN 6.6.x

Resolution

Q: What does the Cluster Health - Advanced vSAN configuration in sync check do?

vSAN has a number of advanced configuration options that can be used for tuning, or to address the special requirements of particular deployments. These advanced configuration options are set on a per ESXi host basis, which makes it easy to create inconsistent advanced setting configurations across a vSAN cluster. This check ensures critical vSAN advanced configuration options have a consistent value across all ESXi hosts in a given vSAN cluster.

Note: This health check is purely done for consistency but not to verify the value is suitable for the environment. If you have set any advanced settings to values that are not appropriate, this check does not highlight this if they have been set to consistently inappropriate values across all the ESXi hosts in the cluster.

Q: What does it mean when it is in an error state?

If this check fails, it means that some advanced configuration settings have different values on different ESXi hosts in the vSAN cluster. The advanced configuration parameter that is not in sync is displayed in the health check details.

Q: How does one troubleshoot and fix the error state?

Check the detailed table to find out which hosts with out of sync on configuration options. Navigate to the problematic host with 'Configure -> System -> Advanced system settings'. Click 'Edit' and change the value of the problem configuration option to be in sync with other hosts.

Notes:

Changing some of the Advanced settings may require a restart of services.
Host profiles is one sure way to keep all nodes in a vSAN cluster consistent, and highlights if any settings are not in sync. For more information, see the vSphere Host Profiles Guide.
This alert may be triggered during ESXi host upgrades in the cluster since ESXi versions will not be the same and some of the values may be different. Once the upgrades are completed the alert should clear.