This topic describes how to purchase a subscription cluster in the PolarDB console.


An Alibaba Cloud account is registered and is used to log on to the Alibaba Cloud Management Console. For more information, see Register and log on to an Alibaba Cloud account.

Background information

A cluster consists of one primary node and a maximum of 15 read-only nodes. To ensure high availability, at least one read-only node is required to implement the active-active architecture. A node is a virtual database server. You can create and manage multiple databases on a node.

  • PolarDB for Oracle supports only Virtual Private Cloud (VPC). Each VPC is an isolated network on Alibaba Cloud and is more secure than the classic network.
  • To optimize the performance of PolarDB, PolarDB clusters need to be deployed in the same internal network with Alibaba Cloud services. We recommend that you deploy PolarDB clusters and Elastic Compute Service (ECS) instances in the same VPC to ensure the optimal performance of PolarDB. If your ECS instance is deployed in the classic network, you must migrate the ECS instance to a VPC.


  1. Log on to the PolarDB console.
  2. In the upper-left corner of the page, click Create Cluster.
  3. Specify Subscription as the value of the Product Type parameter.
  4. Specify the following parameters.
    Parameter Description
    Region The region where the cluster is deployed. You cannot change the region after you purchase the cluster.
    Note Ensure that the PolarDB cluster and the ECS instance to be connected are deployed in the same region. Otherwise, the cluster and the ECS instance cannot communicate through the internal network and can communicate through only the Internet. This compromises the performance.
    Create Type The method to create a PolarDB cluster.
    • Create Primary Cluster: creates a PolarDB cluster.
    • Restore from Recycle: creates a cluster by restoring a backup of a deleted cluster from the recycle bin.
      • Source Version: the version of the cluster that has been deleted.
      • Deleted Clusters: the name of the cluster that has been deleted.
      • Backup History: Select the backup that you want to restore.
    Note You can select other options to create databases of other engines.
    Primary Availability Zone The primary zone where the cluster is deployed.
    • Each zone is an independent geographical location in a region. The zones that are deployed in the same region are similar.
    • You can deploy your PolarDB cluster and ECS instance in the same zone or in different zones.
    • You need to select only the primary zone. The system automatically selects a secondary zone.
    Network Type The value of this parameter can be only VPC. You do not need to select the value of this parameter.


    Ensure that the PolarDB cluster to be created and the ECS instance to be connected are deployed in the same VPC. Otherwise, the cluster and the ECS instance cannot communicate over the internal network to achieve optimal performance.
    • If you have created a VPC that meets your network plan, select the VPC. For example, if you have created an ECS instance and the VPC where the ECS instance is deployed meets your network plan, select this VPC.
    • If you do not create a VPC that meets your network plan, use the default VPC and the default vSwitch.
      • Default VPC:
        • The default VPC is a unique VPC in the selected region.
        • The subnet mask consists of 16 bits, such as A maximum of 65,534 private IP addresses can be provided.
        • The default VPC is not included in the total number of VPCs that you can create.
      • Default vSwitch:
        • The default vSwitch is a unique vSwitch in the selected zone.
        • The subnet mask consists of 20 bits, such as A maximum of 4,094 private IP addresses can be provided.
        • The default vSwitch is not included in the total number of vSwitches that you can create in a VPC.
    • If the default VPC and vSwitch cannot meet your requirements, you can create your own VPC and vSwitch. For more information, see Create and manage a VPC.
    • MySQL 8.0: fully compatible with MySQL 8.0. MySQL 8.0 supports parallel queries. In specific scenarios, the performance increases by 10 times. For more information, see Parallel query.
    • MySQL 5.7: fully compatible with MySQL 5.7.
    • MySQL 5.6: fully compatible with MySQL 5.6.
    • PostgreSQL 11: fully compatible with PostgreSQL 11.
    • Compatible with Oracle Syntax: highly compatible with the Oracle syntax. For more information, see Oracle compatibility.
    Edition By default, this parameter is set to Cluster (2-16 Nodes) (Recommended).
    Node Specification Select the specifications as needed. All the nodes in the PolarDB cluster are dedicated nodes with stable and reliable performance.

    For more information about specifications of compute nodes, see Specifications and pricing.

    Nodes If the source cluster edition is Cluster (2-16 Nodes) (Recommended), the system creates a primary node and a read-only node that have the same specification by default. You do not need to specify this parameter.
    Note If the primary node fails, the system uses the read-only node as the primary node and creates another read-only node. For more information about read-only nodes, see Architecture.
    Storage Cost You do not need to specify this parameter. The system charges you on an hourly basis based on the actual data usage. For more information, see Specifications and pricing.
    Note You do not need to select a storage capacity when you create a cluster. The system automatically scales the storage capacity when the amount of data is increased or decreased.
    Enable TDE Specify whether to enable transparent data encryption (TDE). After TDE is enabled, PolarDB encrypts the data files of your cluster. This operation is transparent to service access. The performance is reduced by 5% to 10%.
    Note You cannot disable TDE after TDE is enabled.
    Cluster Name Enter a cluster name. The name must meet the following requirements:
    • It cannot start with http:// or https://.
    • It must be 1 to 256 characters in length.

    If this parameter is left empty, the system automatically generates a cluster name. You can change the cluster name after the cluster is created.

    Resource Group Select a required resource group from available resource groups. For more information about how to create a resource group, see Create a resource group.
    Note A resource group is a container that contains a group of resources in an Alibaba Cloud account. You can manage these resources in a centralized manner. A resource belongs to only one resource group. For more information, see Use RAM to create and authorize resource groups.
  5. Specify the Purchase Plan and Number parameters, and click Buy Now.
    Note You can create a maximum of 50 clusters at a time. This allows you to create multiple clusters in specific scenarios. For example, you can enable multiple game servers at a time.
  6. On the Confirm Order page, confirm your order information. Read and accept the terms of service, and then click Pay.
  7. On the Purchase page, confirm the unpaid order and the payment method and click Purchase.

    After you complete the payment, it takes 10 to 15 minutes to create the cluster. Then, the newly created cluster is displayed on the Clusters page.

    • If nodes in the cluster are in the Creating state, the cluster is being created and unavailable. The cluster is available only if it is in the Running state.
    • Make sure that you have selected the region where the cluster is deployed. Otherwise, you cannot view the cluster.
    • If you need to store a large amount of data, we recommend that you purchase PolarDB storage plans. Storage plans are more cost-effective than the pay-as-you-go billing method. You are offered larger discounts if you purchase storage plans that provide larger storage capacities. For more information, see Billing method 1: pay-as-you-go.

What to do next

Configure a whitelist for a cluster

Related API operations

API Description
CreateDBCluster Creates a PolarDB cluster.
DescribeDBClusters Queries PolarDB clusters.
DescribeDBClusterAttribute Queries the detailed information about a specified PolarDB cluster.
DescribeAutoRenewAttribute Queries the auto-renewal status of subscription PolarDB clusters.
ModifyAutoRenewAttribute Modifies auto-renewal parameters for a subscription PolarDB cluster.