# Ensure Cloud SQL Instance Has High Availability (REGIONAL) Configured

- Source: https://support.icompaas.com/support/solutions/articles/a_1788888290710844-ensure-cloud-sql-instance-has-high-availability-regional-configured
- Section: [Solutions](https://support.icompaas.com/support/solutions) › [GCP Benchmarks](https://support.icompaas.com/support/solutions/62000112667) › [GCP Knowledge Bases](https://support.icompaas.com/support/solutions/folders/62000169178)
- Last updated: 2026-09-08
- Publisher: iCompaas, Inc. (https://www.icompaas.com)

**Description**

Ensure that production Cloud SQL instances are configured for high availability using the REGIONAL availability type, which maintains a standby replica in a different zone within the same region and automatically fails over if the primary zone becomes unavailable.

**Rationale**

A Cloud SQL instance configured with ZONAL availability runs in a single zone, so a zonal outage, hardware failure, or maintenance event causes a database outage until the instance can be restarted, potentially resulting in extended downtime and data unavailability. REGIONAL (high availability) configuration maintains a synchronously replicated standby instance in a second zone and performs automatic failover, significantly reducing downtime for zonal failures and improving the resilience of production workloads.

**Impact**

-   Reduces downtime from zonal outages or maintenance events through automatic failover
    
-   Improves resilience and business continuity for production database workloads
    
-   Increases cost due to the standby replica, which should be weighed against the availability requirements of the workload
    

**Default Value**

By default, new Cloud SQL instances may be created with ZONAL availability depending on the tier and settings chosen; REGIONAL (high availability) must be explicitly selected.

**Pre-Requisites**

-   IAM permissions to view and edit Cloud SQL instances (e.g., Cloud SQL Admin)
    
-   Awareness of the additional cost associated with the standby replica
    

**Test Plan**

1.  Sign in to the Google Cloud Console at [https://console.cloud.google.com](https://console.cloud.google.com/).
    
2.  Select the relevant project.
    
3.  Navigate to Cloud SQL and select the instance to review.
    
4.  Open the Overview or Configuration section.
    
5.  Verify the Availability type / High availability field shows Multiple zones (REGIONAL) rather than Single zone (ZONAL).
    
6.  If a production instance is configured as ZONAL, follow the implementation steps.
    

**Implementation Steps**

1.  Sign in to the Google Cloud Console at [https://console.cloud.google.com](https://console.cloud.google.com/).
    
2.  Select the relevant project.
    
3.  Navigate to Cloud SQL and select the instance to update.
    
4.  Select Edit.
    
5.  Under Connections / Availability, choose Multiple zones (Highly available).
    
6.  Review the estimated cost impact.
    
7.  Click Save to apply the configuration change.
    
8.  Wait for the instance to restart and confirm that a standby instance now appears in the instance overview.
    

**Backout Plan**

1.  Sign in to the Google Cloud Console at [https://console.cloud.google.com](https://console.cloud.google.com/).
    
2.  Select the relevant project.
    
3.  Navigate to Cloud SQL and select the instance to revert.
    
4.  Select Edit.
    
5.  Under Connections / Availability, choose Single zone.
    
6.  Click Save to apply the configuration change.
    

**Reference**

-   [https://cloud.google.com/sql/docs/mysql/high-availability](https://cloud.google.com/sql/docs/mysql/high-availability)
    
-   [https://cloud.google.com/sql/docs/mysql/instance-settings](https://cloud.google.com/sql/docs/mysql/instance-settings)

## Related compliance guidance

- [SOC 2 compliance: a practical implementation guide for cloud-native SaaS teams](https://support.icompaas.com/compliance/soc-2-trust-services-criteria): Configuration checks like this one are the technical half of a SOC 2 / ISO 27001 programme — the guide shows where they fit, what else an auditor expects, and how to evidence them.
- [ISO/IEC 27001:2022 compliance: a practical implementation guide](https://support.icompaas.com/compliance/iso-27001-2022): ISO 27001 Annex A.8 (technological controls) is where cloud hardening evidence lands; the guide shows how to run the ISMS around it.