VDT output reports a server cannot perform a reverse lookup of the vCenter Server IP

Products

• VMware vCenter Server

Issue/Introduction

• You have run VDT per KB344917 to check the health of your vCenter prior to an upgrade.
• The output of VDT finds reverse lookup of the vCenter Server's FQDN is not possible.
• In the VDT output and logs you see a similar message:

        Nameserver Checks

            • <IP Address>
                [PASS]    DNS with UDP - testing if <vCenter Server FQDN> resolves to <IP Address>
                [PASS]    DNS with TCP - testing if <vCenter Server FQDN> resolves to <IP Address>
                [FAIL]    Reverse DNS - testing if <IP Address> resolves to <vCenter Server FQDN>
                            <IP Address> resolves to .
                                Non-functional reverse DNS is known to cause issues with domain joined VCs (IWA).  
                                Reverse DNS is a requirement of vCenter Server FQDNs.
                            Documentation: 
                                https://docs.vmware.com/en/VMware-vSphere/8.0/vsphere-vcenter-installation/GUID-752FCA83-1A9B-499E-9C65-D5625351C0B5.html
                [INFO]    Commands used:
                          dig +short <fqdn> <nameserver>
                          dig +noall +answer -x <ip> <namserver>
                          dig +short +tcp <fqdn> <nameserver>

Environment

VMware vCenter Server

Cause

Per DNS Requirements for the vCenter Server Appliance, If you plan to use an FQDN for the appliance system name, you must verify that the FQDN is resolvable by a DNS server.

Resolution

Ensure the DNS configuration includes both forward and reverse records.