Commvault backups are failing with error: "Unable to download the configuration file for the virtual machine"

Products

• VMware vCenter Server

Issue/Introduction

Commvault backups are failing with error:  "Unable to download the configuration file for the virtual machine"

When attempted to download a VM configuration file using an "[email protected]" account following error message is seen in vSphere client: 

"No suitable host found for file download. You should have Host > Configuration > System Management privilege on the hosts connected to that datastore in order to download files."

ESXi host client is inaccessible with it's FQDN with error message as below:

Environment

VMware vCenter Server 8.x

Cause

This issue happens when the DNS server in your vSphere environment isn't working correctly, either by being down or unable to resolve names for vCenter Server and ESXi hosts.

Resolution

To fix the issue, ensure that the DNS configuration for vCenter Appliance and ESXi Hosts are correct and both forward and reverse lookups works as expected between the DNS Server , vCenter Appliance and the ESXi host.