VCF Brownfield import sync operation fails with error: Failed to sync domain "Domain_Name" and "ipaddress. NetmaskValueError: 'None' is not a valid netmask"

Products

• VMware SDDC Manager / VCF Installer

Issue/Introduction

When attempting to import an ESXi host using the brownfield import script(vcf_brownfield.py), the synchronization workflow on the VCF SDDC Manager appliance fails.

• When reviewing the script output on the SDDC Manager, you observe entries similar to the following:

  [ INFO] request helper: Response status from fetch all networkPools: 200
  [INFO] sddc_manager helper: Using cached SDDC Manager token header
  [INFO] request helper: Response status from fetch all hosts: 200
  [CRITICAL] vcf brownfield: Failed to sync domain <Domain_Name>
  

• In the error trace for the failure we see:

  ipaddress. NetmaskValueError: 'None' is not a valid netmask

   

  

Environment

VMware Cloud Foundation 5.1.x

VMware Cloud Foundation 5.2.x

Cause

The synchronization failure is caused due to an incorrect subnet mask configured on a VMkernel interface of the ESXi host being added.

The VCF sync operation validates host networking. If the subnet mask value on the new host's VMkernel adapter differs from the subnet mask used by the existing hosts in that workload domain network, the validation fails and the sync is aborted.

Resolution

To resolve the synchronization failure, correct the network configuration on the ESXi host:

1. Correct the VMkernel Settings:

   • Log in to the vSphere Client and navigate to the ESXi host.

   • Go to Configure > Networking > VMkernel adapters.

   • Edit the affected VMkernel interface and change the subnet mask to the correct value.

2. Rerun the Sync Script:

   • SSH into the SDDC Manager appliance as vcf and elevate to root.

   • Execute the sync command again: 

     python3 vcf_brownfield.py sync --domain-name <Domain_Name>

Additional Information

Hosts must be added to the SDDC Manager using this sync script method due to a known limitation with imported environments:

Unable to add the ESXI to a cluster on a brownfield SDDC Manager as it fails with "Cluster is marked as imported,This operation is not allowed on imported Clusters"