Enable and disable high availability

This page describes how to configure an instance for high availability.

You can configure an instance for high availability when you create the instance, or you can enable high availability on an existing instance.

For more information about high availability, see Overview of the high availability configuration.

The legacy configuration for high availability used a failover replica instance. The new configuration does not use a failover replica. Instead, it uses Google's regional persistent disks, which synchronously replicate data at the block level between two zones in a region. If you have an existing MySQL instance that uses the legacy high availability configuration, you can update your configuration to use the current version. For other procedures related to the legacy high availability configuration, see Legacy configuration for high availability.

Create a new instance configured for high availability

When you create an instance and configure it for high availability, Cloud SQL creates it as a regional instance.

To create an instance configured for high availability:

Console

  1. In the Google Cloud console, go to the Cloud SQL Instances page.

    Go to Cloud SQL Instances

  2. Select Create instance.
  3. In the Choose region and zonal availability section, select Multiple zones (Highly available).
  4. Expand Specify zones.
  5. Select the region and the primary and secondary zones. The following conditions apply when the secondary zone is used during instance creation or edit:
    • The zones default to Any for the primary zone and Any (different from primary) for the secondary zone.

      • If both the primary and secondary zones are specified, they must be distinct zones.

  6. Click Save.

    You are returned to the instance page for the primary instance while the instance is updated.

gcloud

  1. Create the regional instance: 
    gcloud sql instances create REGIONAL_INSTANCE_NAME \
--availability-type=REGIONAL \
--database-version=DATABASE_VERSION \
--tier=MACHINE_TYPE \
--enable-bin-log
    For a complete list of available parameters, see the gcloud sql instances create reference page.
  2. You can specify both the primary and secondary zones, using the --zone and --secondary-zone parameters. The following restrictions apply when the secondary zone is used during instance creation or edit:
    • The zones must be valid zones.
    • If the secondary zone is specified, the primary must also be specified.
    • If the primary and secondary zones are specified, they must be distinct zones.
    • If the primary and secondary zones are specified, they must belong to the same region.
  3. Configure the root user: 
    gcloud sql users set-password root --host=% \
--instance=PRIMARY_INSTANCE_NAME \
--password=PASSWORD

Terraform

To create an instance with high availability, use a Terraform resource.

sql_instance_ha/main.tf 
resource "google_sql_database_instance" "mysql_instance_ha" {
  name             = "mysql-instance-ha"
  region           = "asia-northeast1"
  database_version = "MYSQL_8_0"
  settings {
    tier              = "db-f1-micro"
    availability_type = "REGIONAL"
    backup_configuration {
      enabled            = true
      binary_log_enabled = true
      start_time         = "20:55"
    }
  }
  deletion_protection =  "true"
}

REST v1

For the complete list of parameters for this request, see the instances:insert page.

Create the regional instance.

  1. Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-name: The instance name
    • database-version: The database version enum string
    • region The GCP region
    • machine-type The machine type

    HTTP method and URL: 

    POST https://sqladmin.googleapis.com/v1/projects/project-id/instances

    Request JSON body: 

    {
  "name": "instance-name",
  "region": "region",
  "databaseVersion": "database-version",
   "settings": {
     "tier": "machine-type",
     "backupConfiguration": {
         "binaryLogEnabled": true,
         "enabled": true
      },
      "availabilityType": "REGIONAL"
   }
}

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

  2. When the instance finishes initializing, update the root password on the instance:

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-id: The instance ID
    • password: The new root user password

    HTTP method and URL: 

    PATCH https://sqladmin.googleapis.com/v1/projects/project-id/instances/instance-id/users?name=root&host=%25'

    Request JSON body: 

    {
   "name": "root",
   "host": "%",
   "password": "password"}

    To send your request, expand one of these options:

    You should receive a successful status code (2xx) and an empty response.

REST v1beta4

For the complete list of parameters for this request, see the instances:insert page.

Create the regional instance.

  1. Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-name: The instance name
    • database-version: The database version enum string
    • region The GCP region
    • machine-type The machine type

    HTTP method and URL: 

    POST https://sqladmin.googleapis.com/sql/v1beta4/projects/project-id/instances

    Request JSON body: 

    {
  "name": "instance-name",
  "region": "region",
  "databaseVersion": "database-version",
   "settings": {
     "tier": "machine-type",
     "backupConfiguration": {
         "binaryLogEnabled": true,
         "enabled": true
      },
      "availabilityType": "REGIONAL"
   }
}

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

  2. When the instance finishes initializing, update the root password on the instance:

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-id: The instance ID
    • password: The new root user password

    HTTP method and URL: 

    PATCH https://sqladmin.googleapis.com/sql/v1beta4/projects/project-id/instances/instance-id/users?name=root&host=%25'

    Request JSON body: 

    {
   "name": "root",
   "host": "%",
   "password": "password"}

    To send your request, expand one of these options:

    You should receive a successful status code (2xx) and an empty response.

For more details about creating an instance, see Creating Instances.

Configure an existing instance for high availability

Configuring an existing instance for high availability causes a few minutes of downtime while the instance is reconfigured.

To configure an existing instance for high availability:

Console

  1. In the Google Cloud console, go to the Cloud SQL Instances page.

    Go to Cloud SQL Instances

  2. To open the Overview page of an instance, click the instance name.
  3. Click Edit.
  4. In the Choose region and zonal availability section, select Multiple zones (Highly available).
  5. Expand Specify zones.
  6. Select the region and the primary and secondary zones. The following conditions apply when the secondary zone is used during instance creation or edit:
    • The zones default to Any for the primary zone and Any (different from primary) for the secondary zone.

      • If both the primary and secondary zones are specified, they must be distinct zones.

  7. Click Save.

    You are returned to the instance page for the primary instance while the instance is updated.

gcloud

Update the instance to be regional:

gcloud sql instances patch INSTANCE_NAME \
--availability-type REGIONAL \
--enable-bin-log \
--backup-start-time=HH:MM

For reference information, see gcloud sql instances patch.

REST v1

  1. Check the primary instance to see if automatic backups and binary logs are enabled. These are required for high availability instances.

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-id: The instance ID

    HTTP method and URL: 

    GET https://sqladmin.googleapis.com/v1/projects/project-id/instances/instance-id

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

    {
  "kind": "sql#instance",
  "state": "RUNNABLE",
  "databaseVersion": "MYSQL_8_0"
}

    The output contains a section similar to the following:

      "backupConfiguration": {
    "kind": "sql#backupConfiguration",
    "startTime": "12:00",
    "enabled": true,
    "binaryLogEnabled": true
    }

  2. If either enabled or binaryLogEnabled are false, use the instances:patch method to enable them both. To enable backups, set enabled to true and startTime to a value which is the start of the backup window. To enable binary logging, set binaryLogEnabled to true.

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-id: The instance ID (primary or replica)
    • start-time The time in the format "HH:MM"

    HTTP method and URL: 

    PATCH https://sqladmin.googleapis.com/v1/projects/project-id/instances/instance-id

    Request JSON body: 

    {
  "settings":
  {
    "backupConfiguration":
    {
      "startTime": "start-time",
      "enabled": true,
      "binaryLogEnabled": true
    }
  }
}

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

  3. Update the instance to be a regional instance:

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-name: The instance name

    HTTP method and URL: 

    PATCH https://sqladmin.googleapis.com/v1/projects/project-id/instances/instance-name

    Request JSON body: 

    {
  "settings": {"availabilityType": "REGIONAL" }
}

    To send your request, expand one of these options:

    You should receive a successful status code (2xx) and an empty response.

REST v1beta4

  1. Check the primary instance to see if automatic backups and binary logs are enabled. These are required for high availability instances.

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-id: The instance ID

    HTTP method and URL: 

    GET https://sqladmin.googleapis.com/sql/v1beta4/projects/project-id/instances/instance-id

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

    {
  "kind": "sql#instance",
  "state": "RUNNABLE",
  "databaseVersion": "MYSQL_8_0"
}

    The output contains a section similar to the following:

      "backupConfiguration": {
    "kind": "sql#backupConfiguration",
    "startTime": "12:00",
    "enabled": true,
    "binaryLogEnabled": true
    }

  2. If either enabled or binaryLogEnabled are false, use the instances:patch method to enable them both. To enable backups, set enabled to true and startTime to a value which is the start of the backup window. To enable binary logging, set binaryLogEnabled to true.

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-id: The instance ID (primary or replica)
    • start-time The time in the format "HH:MM"

    HTTP method and URL: 

    PATCH https://sqladmin.googleapis.com/v1beta4/projects/project-id/instances/instance-id

    Request JSON body: 

    {
  "settings":
  {
    "backupConfiguration":
    {
      "startTime": "start-time",
      "enabled": true,
      "binaryLogEnabled": true
    }
  }
}

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

  3. Update the instance to be a regional instance:

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-name: The instance name

    HTTP method and URL: 

    PATCH https://sqladmin.googleapis.com/sql/v1beta4/projects/project-id/instances/instance-name

    Request JSON body: 

    {
  "settings": {"availabilityType": "REGIONAL" }
}

    To send your request, expand one of these options:

    You should receive a successful status code (2xx) and an empty response.

Initiate failover

Testing failover is optional, but is recommended so that you can see how your application responds in the event of a failover.

To learn more about failovers, see the Failover overview.

gcloud

Initiate the failover:

gcloud sql instances failover PRIMARY_INSTANCE_NAME

REST v1

  1. Describe the primary instance to get the value of the settingsVersion field.

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-id: The instance ID

    HTTP method and URL: 

    GET https://sqladmin.googleapis.com/v1/projects/project-id/instances/instance-id

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

    {
  "kind": "sql#instance",
  "state": "RUNNABLE",
  "databaseVersion": "MYSQL_8_0"
}
  2. Initiate the failover:

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-name: The instance name
    • settings-version: The settingsVersion from instanceInfo

    HTTP method and URL: 

    POST https://sqladmin.googleapis.com/v1/projects/project-id/instances/instance-name/failover

    Request JSON body: 

    {
  "failoverContext":
     {
        "settingsVersion":"settings-version"
     }
}

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

REST v1beta4

  1. Describe the primary instance to get the value of the settingsVersion field.

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-id: The instance ID

    HTTP method and URL: 

    GET https://sqladmin.googleapis.com/sql/v1beta4/projects/project-id/instances/instance-id

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

    {
  "kind": "sql#instance",
  "state": "RUNNABLE",
  "databaseVersion": "MYSQL_8_0"
}
  2. Initiate the failover:

    Before using any of the request data, make the following replacements:

    • project-id: The project ID
    • instance-name: The instance name
    • settings-version: The settingsVersion from instanceInfo

    HTTP method and URL: 

    POST https://sqladmin.googleapis.com/sql/v1beta4/projects/project-id/instances/instance-name/failover

    Request JSON body: 

    {
  "failoverContext":
     {
        "settingsVersion":"settings-version"
     }
}

    To send your request, expand one of these options:

    You should receive a JSON response similar to the following:

The instance fails over and is not available to serve data for a few minutes.

Verify an instance has high availability

To verify an instance has high availability:

Console

  1. In the Google Cloud console, go to the Cloud SQL Instances page.

    Go to Cloud SQL Instances

  2. To open the Overview page of an instance, click the instance name.
  3. In the Configuration section, it shows Highly available (regional).

gcloud

gcloud sql instances describe INSTANCE_NAME
The output indicates availabilityType is REGIONAL.

REST v1

Before using any of the request data, make the following replacements:

  • project-id: The project ID
  • instance-id: The instance ID

HTTP method and URL: 

GET https://sqladmin.googleapis.com/v1/projects/project-id/instances/instance-id

To send your request, expand one of these options:

You should receive a JSON response similar to the following:

{
  "kind": "sql#instance",
  "state": "RUNNABLE",
  "databaseVersion": "MYSQL_8_0"
}

The output indicates availabilityType is REGIONAL.

REST v1beta4

Before using any of the request data, make the following replacements:

  • project-id: The project ID
  • instance-id: The instance ID

HTTP method and URL: 

GET https://sqladmin.googleapis.com/sql/v1beta4/projects/project-id/instances/instance-id

To send your request, expand one of these options:

You should receive a JSON response similar to the following:

{
  "kind": "sql#instance",
  "state": "RUNNABLE",
  "databaseVersion": "MYSQL_8_0"
}

The output indicates availabilityType is REGIONAL.

Disable high availability on an instance

Before you perform this procedure, make sure there are no operations currently running on the instance.

To disable high availability:

Console

  1. In the Google Cloud console, go to the Cloud SQL Instances page.

    Go to Cloud SQL Instances

  2. To open the Overview page of an instance, click the instance name.
  3. Click Edit.
  4. Open Auto backups.
  5. In the Availabilitysection, click Single zone.
  6. Click Save. This edit requires a restart of the instance.
  7. When you see the message box, click Save and restart.

gcloud

For reference information, see gcloud sql instances patch. 
gcloud sql instances patch INSTANCE_NAME \
--availability-type ZONAL

REST v1

The following request uses the instances:patch method to change the availability type on the instance to ZONAL.

Before using any of the request data, make the following replacements:

  • project-id: The project ID
  • instance-name: The instance name

HTTP method and URL: 

PATCH https://sqladmin.googleapis.com/v1/projects/project-id/instances/instance-name

Request JSON body: 

{
  "settings": {"availabilityType": "ZONAL" }
}

To send your request, expand one of these options:

You should receive a successful status code (2xx) and an empty response.

REST v1beta4

The following request uses the instances:patch method to change the availability type on the instance to ZONAL.

Before using any of the request data, make the following replacements:

  • project-id: The project ID
  • instance-name: The instance name

HTTP method and URL: 

PATCH https://sqladmin.googleapis.com/sql/v1beta4/projects/project-id/instances/instance-name

Request JSON body: 

{
  "settings": {"availabilityType": "ZONAL" }
}

To send your request, expand one of these options:

You should receive a successful status code (2xx) and an empty response.

Troubleshoot

Issue Troubleshooting
You can't find the metrics for a manual failover. Only automatic failovers go into the metrics.
Cloud SQL instance resources (CPU and RAM) are near 100% usage, causing the high availability instance to go down. The instance machine size is too small for the load.

Edit the instance to upgrade to a larger machine size to get more CPUs and memory.

What's next