Last week, I attempted to upgrade a vCenter Server from version 7.0.3 to 8.0. During the upgrade process, I received an error message along with a resolution:
Error: The source appliance FQDN must be the same as the source appliance primary network identifier.
Resolution: Change the source appliance FQDN according to the officially supported process https://blogs.vmware.com/vsphere/2019/08/changing-your-vcenter-servers-fqdn.html
Somehow, the appliance FQDN was tattood with a host name in upper case when it needed to be all lower case.
Changing the appliance FQDN to all lower case is fairly straight forward and can be performed using the VAMI to change the Hostname in the Network Settings. However, when clicking the link to edit the Network Settings, after selecting the network adapter, the settings for the selected network adapter are blocked from view with a solid black box. This appears to be a UI bug in the VAMI (the same issue no longer exists in vCenter 8). As a result, the Network Settings cannot be reliably changed using this method.
Fortunately, another method exists to change network settings via command line. It’s spelled out in Michls Tech Bog here. In short, SSH into the vCenter Server appliance and run the following command:
/opt/vmware/share/vami/vami_config_net
A menu will be presented with one of the options providing the ability to set the Hostname.
After setting the Hostname, restart the VCSA as well as the upgrade process.