SSAS impersonation error

[Anonymous]

Hi there, I have strange error having two reports that connects to SSAS database.

User A log in Power BI to see a report and he receives an error: "Couldn't load the schema for the database model" either the user B does not have access to the source database. (He is user A, and error refers to a user B who has no access).

A second situation with the same user A, who published and configured the connnection to get refreshed data, is tracked on the refresh history for another report extracting data from the same SSAS database mentioning the user B has no access.

There is a connection created on the gateway to the SSAS database. And user B has no access to it.

As a summary User A receives errors from a different user B.
Any idea of what could be happening here?

[v-qiuyu-msft]

Hi @Anonymous,

From your description, it looks like when the user A access the report which connects to SSAS, Power BI uses user B credential to access SSAS database, right? 

On Power BI service, when we access the report connects to SSAS, the current logged in Power BI email address is passed to SSAS as effective user, if there is no Map User Name configured in gateway for SSAS data source. You can go through this article to get more information: https://docs.microsoft.com/en-us/power-bi/service-gateway-enterprise-manage-ssas#usernames-with-analysis-services

In your scenario, I would suggest you first check if UPN for the user A indeed has permission to access the SSAS database. Then please go to Manage Gateways section, find the SSAS data source, check if you have define any mapping role for the user A. 

Best Regards,
Qiuyun Yu 

[Anonymous]

we setup below properties on config file where the gateway service is installed

   <setting name="ADUserNameReplacementProperty" serializeAs="String">
    <setting name="ADUserNameLookupProperty" serializeAs="String">

to avoid using mapping on each SSAS gateway connection.

The user B has no access which is correct, but the strange thing is the error appeared to user A trying to access the report being logged as user A.  And user B never tried to access the report.

[v-qiuyu-msft]

Hi @Anonymous,

Please check if the Power BI account for User A (firstName.lastName@xxx.com) matches a defined UPN within the local Active Directory Domain which SSAS belong to, and this UPN has permission to access the SSAS instance. 

If there is no problem, I would suggest you create a support ticket to let engineers look into the issue on your side. 

Best Regards,
Qiuyun Yu