PolarDB:Custom purchase

Step 1: Select billing and region

1. Go to the PolarDB Custom Purchase page.

2. Select a Billing Method.

   Note

   You can change the billing method at any time.

   Billing method	How it works	Best for
   Subscription	Pay upfront for a fixed term. Longer terms receive larger discounts.	Predictable, steady workloads
   Pay-as-you-go	Pay based on actual resource usage with no upfront commitment.	Fluctuating or unpredictable workloads

3. Select a Region. Deploying the PolarDB cluster in the same zone as your ECS instance further reduces network latency.

   Important

   The region cannot be changed after the cluster is created. Deploy your PolarDB cluster in the same region as the Elastic Compute Service (ECS) instance that runs your application. Otherwise, the cluster and instance can only communicate over the Internet, which degrades performance. For more information, see Regions and zones.

Step 2: Select a creation method

Select a Creation Method.

Step 3: Configure the engine

Set the following engine and edition parameters.

For compute node specifications, see Specifications of compute nodes.

Step 4: Configure networking

1. Select a Primary Zone. A zone is an independent physical location within a region. All zones in a region provide the same level of service performance.

2. Configure the Network Type. The network type is fixed as VPC. Select a VPC and vSwitch for the cluster.

   • Use an existing VPC: If your ECS instance is already in a VPC that meets your requirements, select that VPC to enable internal network communication.

   • Use the default VPC and vSwitch: If no existing VPC meets your needs, use the defaults: | Resource | Details | |---|---| | Default VPC | Uses a 16-bit subnet mask (for example, 192.168.0.0/16) with up to 65,536 private IP addresses. Does not count against your VPC quota. | | Default vSwitch | Uses a 20-bit subnet mask (for example, 192.168.0.0/20) with up to 4,096 private IP addresses. Does not count against your vSwitch quota. |

   • Create a custom VPC: For specific networking requirements, create a VPC.

Step 5: Set the high-availability mode

Select a High-availability Mode.

For more information, see High-availability mode.

If you select Enable Hot Standby Storage Cluster, configure a Secondary Zone. Automatically Allocated is supported.

Step 6: Configure nodes and storage

1. Select the Node specifications for compute nodes. See Specifications of compute nodes.

2. Set the number of Nodes. By default, the cluster has one primary node and one read-only node. The cluster must have one primary node. Add at least one read-only node to ensure high availability.

3. Select a Storage Type.

   Important

   The storage type cannot be changed after the cluster is created. To switch storage types, create a new cluster and migrate your data. For a detailed comparison, see How to choose between PSL4 and PSL5.

   Storage type	Description	Can change later
   PSL5	Higher performance, reliability, and availability. Supported in historical versions of PolarDB.	No
   PSL4	Uses smart-SSD technology to compress and decompress data at the physical SSD level, reducing storage costs while maintaining high performance.	No

4. (Subscription only) Select a Storage Billing Method. This parameter is available only when Billing Method is set to Subscription. For more information, see Billing rules for storage.

   Storage billing method	Description
   Pay-as-you-go	Storage capacity scales dynamically. You are charged for actual usage.
   Subscription	Purchase a specific amount of storage capacity upfront.

5. (Subscription only) Set the Storage Capacity. This parameter is available only when both Billing Method and Storage Billing Method are set to Subscription. Valid values: 10 GB to 500 TB. The value must be a multiple of 10 GB.

Step 7: Configure advanced options (optional)

Step 8: Confirm and pay

1. On the right side of the page, verify that all parameters (Billing Method, Region, Resource Group, and others) are correct.

2. Set the Quantity (number of clusters to purchase).

   Note

   • You can create a maximum of 50 clusters at a time.

   • You can purchase a maximum of 50 clusters with your Alibaba Cloud account.

3. (Subscription only) Set the Duration and specify whether to enable Auto-renewal.

   Note

   Enable Auto-renewal to prevent service interruptions from overdue payments.

4. Review the total cost and detailed cost breakdown (compute specifications, storage, and network). Read the terms of service. If you agree, click Buy Now.

5. On the Payment page, confirm the order and payment method, and click Subscribe.