Administrators may see the following error message when trying to add a new Delivery Controller to an existing CVAD site:
"An Error occurred with the Database. Contact Citrix Technical support."

Configuration Logging settings can prevent modification to the database.

Disabling configuration logging temporarily before adding the new delivery controller will allow the required changes to the database. After adding the new DDC, configuration logging can be enabled again. Configuration logging for the site can be enabled or disabled via GUI or powershell.
GUI Method:
Powershell Method:
https://support.citrix.com/external/article/CTX139447/how-to-disable-or-enable-configuration-l.html
Administrators may see an error message when trying to add a new Delivery Controller to an existing CVAD site.