Developers cannot reach a Cloud SQL instance in a Shared VPC from on-prem after creating private services access; on-prem connectivity uses Dedicated Interconnect and Cloud Router. How to fix routing?

The correct solution involves two key steps. First, the VPC Network Peering connection used for Private Services Access (PSA) needs to be configured to import and export custom routes. By default, peering connections do not exchange custom routes. Second, the Cloud Router managing the Dedicated Interconnect connection to on-premises must be configured to advertise the Cloud SQL reserved IP range. This ensures that the on-premises network learns the route to the Cloud SQL instance through the Interconnect and the peered network. Incorrect options: Changing the VPC routing mode to global is not sufficient; it primarily affects how subnet routes are advertised and doesn't directly address custom route exchange over peering or advertising the Cloud SQL range to on-prem. Creating an additional Cloud Router in a different region is unnecessary and doesn't solve the fundamental routing issue between the peered network and on-premises. Changing the VPC routing mode to global and modifying peering for custom routes still misses the crucial step of explicitly advertising the Cloud SQL IP range from the Cloud Router to on-premises.