Power BI Report Server Architecture Question

[Coffeehouse45]

Hey All, 

We are planning a new architecture, and are considering switching to Power BI from another visualization app. We are also beginning a project to build a new Enterprise Data Warehouse. This new infrastructure ought to cover the following components: 

SSAS

Power BI Report Server

SQL Server Database Engine
ReportServerDB for Power BI report Server. 

We have a 4 core SQL Server 2019 Enterprise License with Software Assurance. 
The current design is as follows: 
Server A: Hosts -- Power BI Report Server
Server B: Hosts -- SQL server Database Engine, SSAS, ReportServerDB (Report Server Catalog)

My understanding is that SQL Server Enterprise edition Software assurance provides us licensing for Power BI Report Server in addition to the other services that I mentioned. 
Will the license cover all servcies for Server A and B as described above? or does Power BI need to be installed on Server B as well? 

Lastly, Any idea how much overhead ReportServerDB (Report Server Catalog) will require? Our current setup utilizes Tableau, which has an internal Report Server Catalog deployed via PostgreSQL on the same server that Tableau is installed on. It would seem to me that a difference here is that Microsoft is pushing the Report Server Catalog off of Server A to Server B. Is that correct? or am I just completely misreading the documentation? 

thanks!

[josef78]

Yes, SQL Server Enterprise License with Software Assurance cover all these products (SQL Server, Power BI Report Server and Analysis Services).

But, if you have 4 core licences (2x 2core pack) and if your servers are virtual, it is not enough for two server configuration, you need 4core for server A and and 4core for server B (at least). There two solutions, buy more licences. Or place licence on physical server with 4core procesor, where you can run any number virtual servers, with any number of virtual cores.

Two server configuration (with mixed SQL and SSAS) is also not good practice, is better three seperated (virtual) servers, one for MSSQL, second for SSAS, and third for Power BI Report Server (at least).

Utilization of MSSQL (for Report Server catalog) is low, there absolutelly enough use SQL Server Standard without SA.