When adding a new Delivery Controller to an existing Citrix Virtual Apps and Desktops Site, the Controller must register itself and update configuration information stored in the Site database. Citrix documentation explains that specific SQL Server permissions are required for this operation.

To successfully add a Delivery Controller to an existing Site, the administrator performing the task must have:

securityadmin – Allows management of logins and permissions required so the Controller can create and configure its service accounts in the database.

db_owner – Ensures the Controller can modify schema objects, write necessary configuration data, and register itself correctly within the existing Site database.

These permissions are the minimum required for joining a Controller to a Site. Other permission combinations listed (such as dbcreator or db_datawriter) are used for different tasks, such as creating new databases or running maintenance, and are not sufficient for joining a Controller to an existing environment.

Documentation References:

Citrix Virtual Apps and Desktops Installation Guide → Database Permissions Requirements

Citrix Delivery Controller Installation Requirements → SQL Role Requirements for Joining an Existing Site