Connecting from Cloud Run (fully managed) to Cloud SQL

This page contains information and examples for connecting to a Cloud SQL instance from a service running in Cloud Run (fully managed).

Cloud SQL is a fully-managed database service that makes it easy to set up, maintain, manage, and administer your relational databases in the cloud.

Setting up a Cloud SQL instance

  1. Enable the Cloud SQL Admin API in the project you are connecting from, if you haven't already done so:

    Enable the API

  2. Create a Cloud SQL for SQL Server instance.

    By default, Cloud SQL assigns a public IP address to a new instance. Cloud Run (fully managed) does not support connecting to Cloud SQL for SQL Server over public IP. Use private IP instead. For more information, see Configuring private IP.

Configuring Cloud Run (fully managed)

The steps to configure Cloud Run (fully managed) depend on the type of IP address you assigned to your Cloud SQL instance.

Public IP (default)

Cloud Run (fully managed) does not support connecting to Cloud SQL for SQL Server over public IP. Use private IP instead.

Private IP

A Serverless VPC Access connector handles communication to your VPC network. To connect directly with private IP, you need to:

  1. Make sure that the Cloud SQL instance created above has a private IP address. If you need to add one, see the Configuring private IP page for instructions.
  2. Create a Serverless VPC Access connector in the same VPC network as your Cloud SQL instance.
  3. A connector must be in the same project and region as the resource that uses it, but the connector can send traffic to resources in different regions.

    Serverless VPC Access supports communication to VPC networks connected via Cloud VPN and VPC Network Peering.

    Serverless VPC Access does not support legacy networks or Shared VPC.

  4. Configure Cloud Run (fully managed) to use the connector.
  5. Connect using your instance's private IP and port 1433.

Connecting to Cloud SQL

After you configure Cloud Run (fully managed), you can connect to your Cloud SQL instance. Cloud Run (fully managed) provides a mechanism that connects using the Cloud SQL Proxy.

Public IP (default)

Cloud Run (fully managed) does not support connecting to Cloud SQL for SQL Server over public IP. Use private IP instead.

Private IP

Connecting with TCP

Connect directly using the private IP address and port 1433 for your instance.

Best practices & other information

You can use the Cloud SQL proxy when testing your application locally. See the quickstart for using the proxy for local testing for detailed instructions.

You can also test using the Cloud SQL Proxy via a docker container.

Connection Pools

Connections to underlying databases may be dropped, either by the database server itself, or by the platform infrastructure. We recommend using a client library that supports connection pools that automatically reconnect broken client connections. For more detailed examples on how to use connection pools, see the Managing database connections page.

Connection Limits

Both the MySQL and PostgreSQL editions of Cloud SQL impose a maximum limit on concurrent connections, and these limits may vary depending on the database engine chosen (see the Cloud SQL Quotas and Limits) page. Cloud Run (fully managed) can automatically create more instances as load increases, which may cause you to exceed these limits. You can limit the maximum number of connections used per instance by using a connection pool. For more detailed examples on how to limit the number of connections, see the Managing database connections page.

API Quota Limits

Cloud Run (fully managed) provides a mechanism that connects using the Cloud SQL Proxy, which uses the Cloud SQL Admin API. API quota limits apply to the Cloud SQL Proxy.

Next steps