Network configuration is out of sync in vSAN Cluster Congiguration Consistency check

Products

• VMware vSAN

Issue/Introduction

In the vSAN Skyline Health check the alarm for vSAN cluster configuration consistency is in red state. The details of this alert show that one or more hosts has an Issue listed as "Network configuration is out of sync" and a Recommendation of "Remediate inconsistent network configuration". 

The vmware-vsan-health-summary-result log on vCenter will have matching entry similar to:
      Test consistentconfig health : red
         Issues: Host  Disk  Issue  Recommendation
                 (Host-######, '', NetworkConfigurationIsOutOfSync, RemediateInconsistentConfiguration),

Environment

vSAN 7.#

vSAN 8.#

Cause

This alarm is triggered when one or more hosts have  /VSAN/IgnoreClusterMemberListupdates set differently than other hosts in the cluster.

This can be checked by running esxcfg-advcfg -g /VSAN/IgnoreClusterMemberListupdates on all hosts in the cluster and ensuring the have matching values. Result of command as:
esxcfg-advcfg -g /VSAN/IgnoreClusterMemberListupdates
Value of IgnoreClusterMemberListupdates is 1
or
esxcfg-advcfg -g /VSAN/IgnoreClusterMemberListupdates
Value of IgnoreClusterMemberListupdates is 0

Resolution

Ensure all hosts are set to the same value. 
This can be achieved with the following command being run on the hosts needing to be changed to match the remainder of the cluster:

To set default: esxcfg-advcfg -s 0 /VSAN/IgnoreClusterMemberListupdates
If there is a reason support has asked the seeting to be enabled: esxcfg-advcfg -s 1 /VSAN/IgnoreClusterMemberListupdates 


Followed by ensuring the setting succeeded:
esxcfg-advcfg -g /VSAN/IgnoreClusterMemberListupdates

To understand the full range of potential impact and risk please see KB 326427 - Configuring vSAN Unicast networking from the command line.

Additional Information

KB 326880 - vSAN Cluster Configuration Consistency