Hello i want connect my cloud sql to linked server through public ip where is located another MSSQL instances but i just get the next error: “Login timeout”
I have already achieved to use the linked server with an instance located in a VPC of my local network in google
Connecting a Cloud SQL for SQL Server instance to an external SQL Server over public IP can be challenging due to the secure and managed nature of Cloud SQL. Unlike self-managed SQL Servers on VMs, Cloud SQL instances lack direct outbound internet access and do not allow modifications to network or firewall settings. These limitations often result in “Login timeout” errors when attempting to establish Linked Server connections to external hosts over public IP.
While Linked Servers are supported in Cloud SQL for SQL Server, they are primarily intended for connecting to other Cloud SQL instances within the same environment, such as within the same region or VPC. Using Linked Servers to connect to an external SQL Server over public IP is not a typical use case and is not natively supported without additional networking configurations.
The recommended approach for connecting Cloud SQL to an external SQL Server is to use private IP connectivity. This can be achieved by hosting the external SQL Server on a VM in the same VPC, or by establishing a private network connection via VPN or Interconnect to the external server’s network. These methods provide reliable and secure connectivity, ensuring that Cloud SQL can communicate with the external SQL Server.
When private connectivity is not feasible, alternatives such as data replication or application-level integration should be considered. Tools like Dataproc or Dataflow can be used to replicate data between the databases, while application code can manage connections to both environments independently.
If Linked Servers must be used, ensure that the external SQL Server is configured to allow remote connections, that firewall rules permit traffic from Cloud SQL, and that DNS resolution is properly set up. However, private connectivity remains the most secure and effective solution for seamless integration.