Unable to add/commission Compute only ESXi host to a vSAN cluster via SDDC Manager

Products

• VMware SDDC Manager
• VMware Cloud Foundation

Issue/Introduction

Symptoms:

• Attempting to add/commission Compute only ESXi host to a vSAN cluster via SDDC Manager, the "Validate vSAN disks for ESXi Host(s)" check fails, stating "vSAN Disks Validation on the ESXi Host(s) failed: ESXi Host <host_fqdn> found zero SSD devices for SSD cache tier, .....................":

  

• The compute only ESXi host has no storage devices which will contribute to the vSAN datastore.

Environment

VMware SDDC Manager 5.x

VMware Cloud Foundation 5.x

Cause

• This issue occurs due to the compute only ESXi not having any disks/devices which are eligible for use by vSAN.

• The SDDC manager will prevent addition of ESXi host to a vSAN cluster which do not contribute to the vSAN datastore.

 

Note: Broadcom does not recommend having unbalanced cluster configurations, and thus minimize significant levels of asymmetry. This will help prevent potential availability and capacity issues during failure conditions, and minimize deviation in performance

Resolution

Workaround:

1. Take a snapshot of the SDDC Manager appliance.

2. SSH to the SDDC Manager with user vcf and then elevate to root using "su root" command.

3. Once logged into SSH of SDDC Manager as root, proceed to add the below property to the file /etc/vmware/vcf/domainmanager/application.properties: (Use the cli vi editor to edit the file)

   validation.disable.vsan.disks.check=true

4. Save the file and then restart the domain manager service using command:

   systemctl restart domainmanager

5. Now, re-attempt the task of adding the compute node to the vSAN cluster.

6. Once the ESXi host is added to the cluster successfully, remove the line added in step 3 and restart the domain manager service again (step 4).

Additional Information

Unable to add host to the SDDC Manager "HOST_VSAN_DISKS_VALIDATION_FAILED vSan Disks Validation on the ESXi Host(s) failed".