Configuring Kerberos authentication for SSRS in native mode – SSRS 2008 R2-2012-Collection of common programming errors

Hi pscorca,

If we have applications that only use Kerberos authentication and we are using RSWindowsNegotiate AuthenticationType, we must create a Service Principal Name (SPN) for the Report Server service if we configure it to run as a domain user account.

Before setting up constrained delegation, we must register a Service Principle Name (SPN) for the Analysis Services instance. We will need the Analysis Services SPN when configuring Kerberos constrained delegation for middle tier services.

There is a document about Enabling Kerberos Authentication for Reporting Services, you can refer to it.
http://blogs.technet.com/b/rob/archive/2011/11/23/enabling-kerberos-authentication-for-reporting-services.aspx

Hoe this helps.

Regards,
Alisa Tang