"Unable to find the source appliance on the specified ESXi host or vCenter Server" error during stage 1 of VCSA upgrade

Products

• VMware vCenter Server

Issue/Introduction

• During the Stage1 of the vCenter server appliance upgrade after the Source vCenter details are entered to connect to the Source appliance, it fails with the error below
  "Unable to find the source appliance on the specified ESXi host or vCenter Server"
  

• UI installer logs have the below entries: 
  [YYYY-MM-DDTHH:MM:SS]  - debug: MASKEDVCNAME.masked.fqdn: dnsResolve result for IPv4 : undefined
[YYYY-MM-DDTHH:MM:SS]  - warn: DNS is not resolved to IPv4: Error: queryA ENOTFOUND MASKEDVCNAME.masked.fqdn
[YYYY-MM-DDTHH:MM:SS]  - debug: MASKEDVCNAME.masked.fqdn: dnsResolve result for IPv6 : undefined
[YYYY-MM-DDTHH:MM:SS]  - warn: DNS is not resolved to IPv6: Error: queryAaaa ENOTFOUND MASKEDVCNAME.masked.fqdn
[YYYY-MM-DDTHH:MM:SS]  - debug: getVmWithIPFQDN: hostName MASKEDVCNAME.masked.fqdn is associated with []
[YYYY-MM-DDTHH:MM:SS]  - debug: ips associated with MASKEDVCNAME.masked.fqdn: []
[YYYY-MM-DDTHH:MM:SS]  - debug: token:undefined, length:15, running total:15
[YYYY-MM-DDTHH:MM:SS]  - error: No VM found with hostname MASKEDVCNAME.masked.fqdn
[YYYY-MM-DDTHH:MM:SS]  - error: Error in getting VM: MASKED_IP_ADDRESS ,Error: {"message":"No VM found with hostname MASKEDVCNAME.masked.fqdn"}
[YYYY-MM-DDTHH:MM:SS]  - error: Failed to read the nodetype, Error: No VM found with hostname MASKEDVCNAME.masked.fqdn
[YYYY-MM-DDTHH:MM:SS]  - error: The source specified does not manage source VC, source host= MASKED_IP_ADDRESS ,error:[object Object]
[YYYY-MM-DDTHH:MM:SS]  - debug: Source Host IP address in DOM input value is: MASKED_ESXi_NAME
[YYYY-MM-DDTHH:MM:SS]  - debug: Source Host IP Value in data model is: MASKED_ESXi_NAME
[YYYY-MM-DDTHH:MM:SS]  - debug: Source Host IP Value in data model after correction is: MASKED_ESXi_NAME
[YYYY-MM-DDTHH:MM:SS]  - error: invalid SourceVcForm
  
  

Environment

VMware vCenter 7.x 
VMware vCenter 8.x

 

Cause

This issue occurs when there is a mismatch due to case sensitivity between the source vCenter's PNID and the hostname of the VCSA entered in the details of the Source vCenter Appliance during Stage1.

Resolution

• Cancel the upgrade.
• Login to the source VCSA via SSH and note down the PNID of the vCenter with the command:
  
  /usr/lib/vmware-vmafd/bin/vmafd-cli get-pnid --server-name localhost
  
  
• Launch the UI installer and restart the upgrade process.
• During Stage 1, at the "Connect to Source appliance" step, enter the PNID of the vCenter Server noted earlier and proceed further with the upgrade.