vSAN Health Warning - "vSAN extended configuration in sync" on vSAN

Products

• VMware vSAN

Issue/Introduction

This article explains the purpose of the Cluster Health - "vSAN extended configuration in sync" and provides details on why it might report an error.
Automatic Rebalance was turned on which is not supported on ESXi version 6.7.0 

Environment

VMware vSAN 6.x
VMware vSAN 7.x
VMware vSAN 8.x

Cause

Automatic Rebalance was turned on which is not supported on ESXi version 6.7.0

Resolution

Q: What does it check?

vSAN has several advanced settings with default values, if some of these settings are changed, this alarm will be triggered.

Q: Which settings are checked?

- Object repair time
- Site read locality
- Customized swap object
- Large scale cluster support
- Configurations have taken effect

         -  Automatic Rebalance

 

 Q: What does it mean when it is on a error state?

It means that some of the advanced settings monitored by this check were changed. You can see what settings and on which hosts if you expand the alarm.

Q: What can be done to remediate this alarm?

You can click on the "Remediate inconsistent configuration" button. This action overrides existing vSAN cluster configuration on all the ESXi hosts in this vCenter cluster. Make sure you have all the ESXi hosts from the vSAN cluster added to the vCenter cluster.
Also make sure that all vSAN configuration in vCenter is accurate (including host fault domain settings, de-duplication settings, encryption settings, Automatic Rebalance and so on) because any mis-configuration pushed down at this stage can reconfigure this vSAN cluster, causing server side-effects.

Q: What are the default values?

Object repair timer: 60 minutes
Site read locality: Enabled
Customized swap object: Enabled
Large scale cluster support: Disabled

         Automatic Rebalance > Disable

 

Turned off the Automatic Rebalance from the Advanced setting option and performed the skyline health test and the error was no more reported .

1. Navigate to the vSAN cluster.
2. Click the Configure tab.
3. Under vSAN, select Services.
4. Click to edit Advanced Options.
5. Click to enable or disable Automatic Rebalance.
6. Set the variance threshold to any percentage from 20 to 75 as per your requirement