ADD_HOST operation validation failed due to : Entity: <hostname> with failed check: Cluster Host Data Check with Severity Critical.

Products

• VMware SDDC Manager

Issue/Introduction

While attempting to add a new or re-commissioned host to an SDDC managed vSAN cluster, there is an error in the domain manager logs:

ADD_HOST operation validation failed due to : Entity: <hostname> with failed check: Cluster Host Data Check with Severity Critical.

and

Filtered check results are [class LambdaCheckResultRest  ( 
      entityName: <ClusterName> 
      entityType: cluster 
      description: Validates that there is no mismatch between the hosts in the cluster and the SDDC manager inventory 
      resultMessage: There is a mismatch between the hosts in the cluster and the SDDC Manager Inventory. 
      severity: CRITICAL 
      status: VALIDATION FAILED 
      remediation: Sync the SDDC Manager inventory with the accurate state of the cluster 
      name: Cluster Host Data Check 

In the SDDC Manager, the host is in the cluster, but in the vSphere client, the host is not in the cluster.

 

Environment

SDDC Manager 5.2.x

Cause

The cause of this issue was the fact that the previous attempt to add the host to the cluster failed after it was added on the SDDC side, but not on the vSphere side.

Resolution

In order to resolve this issue, we performed the following:

1. Decommission the host from the SDDC manager.
2. Log into the host via SSH and run a the following commands:
   
    - "df -h" The results showed us there there were no vSAN datastores attached to the host.
   
    - "esxcfg-vswitch -l"
   
   This should show that there are no vDS entries or vSAN datastores in the host configuration.
3. Because these two things are not present on the host, it is okay to commission the host again on the SDDC Manager. (If there are vSAN datastores and/or DVS entries, the host will have to be re-imaged and imported back into the cluster as a new host.) 
4. Re-add the host to the cluster.