What was the errors you were seeing as it relates to failed connections to vSphere? Note that SSL management changed and if you are using self-signed certs for vSphere/NSX, you must re-accept these certs post-10.1 upgrade. I wrote about this new behavior here: https://www.paluszek.com/wp/2020/04/10/upgrading-to-vmware-cloud-director-10-1-ssl-management-changes/
I want to thank you for a quick reply to my question. Your propose to simply re-enter credentials for vSphere and accept self-signed certificates worked. Never even thought about trying this simple solution. Thought it was some sort of a DB upgrade problem. Thank you very much!
p.s. Another great blog goes to my "favorites" tab