Where are connections to databases made from when using SSRS? If I have SSRS set up in the following format

Server 1 : Running SQL Server, hosting the SSRS database

Server 2 : Running SSRS, configured to store metadata on Server 1 database

And SSRS reports are configured to connect to say, Server 3

Will the connection to server 3 take place from server 1 or server 2?
From Server2 to Server3.  The SSRS service is what connects to the database which contains the database which the report is querying.