Known issues

This page lists known issues with Cloud SQL for SQL Server, along with ways you can avoid or recover from these issues.

Instance connection issues

  • Expired SSL/TLS certificates

    If your instance is configured to use SSL, go to the Cloud SQL Instances page in the Cloud Console and open the instance. Open its Connections page, select the Security tab and make sure that your server certificate is valid. If it has expired, you must add a new certificate and rotate to it.

  • Cloud SQL Auth proxy version

    If you are connecting using the Cloud SQL Auth proxy, make sure you are using the most recent version. For more information, see Keeping the Cloud SQL Auth proxy up to date.

  • Not authorized to connect

    If you try to connect to an instance that does not exist in that project, the error message only says that you are not authorized to access that instance.

Administrative issues

  • A large export operation can adversely affect instance availability

    Before starting a large export, ensure that at least 25 percent of the database size is free (on the instance). Doing so helps prevent issues with aggressive autogrowth, which can affect the availability of the instance.

  • If your SQL Server instance uses a SQL Server Express edition:

    • If you specify a flag when you create a new instance, creation of the instance fails.

    • You cannot set database flags on an existing instance.

  • Long-running Cloud SQL instance operations can't be cancelled or stopped

    Only one operation can run at a time on a Cloud SQL instance. For this reason, make sure you don't need to perform other operations on an instance when you start a long-running operation.

    When you start a long-running Cloud SQL instance operation, such as an import or export operation, there's no way to cancel the operation without restarting the instance.

  • Instance names cannot be reused immediately after instance deletion

    After you delete an instance, you cannot immediately reuse the instance name, because Cloud SQL reserves that name for a few days. If you need to create and delete instances with the same name, consider using a timestamp as part of the name to avoid name conflicts.

Issues with importing and exporting data

  • Do not create a BAK file (for import) from a read-only database or from a database that is in single-user mode. If you create a BAK file from a read-only database or from a database that is in single-user mode, and import that file, an error may occur.

  • Cloud Storage supports a maximum single-object size up five terabytes. If you have databases larger than 5TB, the export operation to Cloud Storage fails. In this case, you need to break down your export files into smaller segments.

Transaction logs and disk growth

Logs are purged once daily, not continuously. When the number of days of log retention is configured to be the same as the number of backups, a day of logging might be lost, depending on when the backup occurs. For example, setting log retention to seven days and backup retention to seven backups means that between six and seven days of logs will be retained.

We recommend setting the number of backups to at least one more than the days of log retention to guarantee a minimum of specified days of log retention.