There are 2 mssql servers in the environment: SQL1 and SQL2. There is a linked server from sql1 to sql2 using the domain user ad1 (ad1 has permission to read databases on SQL1 and SQL2)
There is an app3 server on which the application is installed, and the ad2 application pool account (domain user) connects to the database on SQL1.
I would like to be able to perform database queries from the application level via linked servers on SQL2. So the question is how to set up a linked server connection to make this operation possible, with only the ad1 user who has permissions to SQL2